How Mosquitoes Use Six Needles to Suck Your Blood

Posted on July 13, 2018

How Mosquitoes Use Six Needles to Suck Your Blood

An Anopheles mosquito bites into a human arm. An Anopheles mosquito bites into a human arm. (Josh Cassidy/KQED)

“Why are some people more likely to get bitten than others?” asked Luckhart. “The volatile fatty acids given off by our skin are quite different. They reflect differences between men and women, even what we’ve eaten. Those cues are different from person to person. There’s probably not one or two. It’s the blend that’s more or less attractive.”

Researchers still haven’t figured out what about their volatile fatty acids makes some people more attractive to mosquitoes than others. What scientists have recently discovered is that once a mosquito’s proboscis pierces the skin, one of its six needles, called the labrum, uses receptors on its tip to find a blood vessel.

“Those receptors responded to the chemicals in the blood,” said UC Davis biochemist Walter Leal, whose lab made the finding. “Mosquitoes don’t find the blood vessel randomly.”

Instead, chemicals in our blood waft up like a “bouquet of smells” that guides the way — unwittingly, but surely — to our blood vessel. The labrum then pierces the vessel and serves as a straw.

UC Davis post-doctoral researcher Young-Moo Choo, in Leal’s lab, discovered a receptor by dissecting mosquitoes’ mouthparts and genetically testing them. Choo hopes his finding of this receptor, called 4EP, and the discovery of other receptors on the labrum, will help drug companies develop new mosquito repellents.

“First they’d need to find a repellent against the receptors,” said Choo. “Then they’d treat people’s skin with it. When the mosquito tried to penetrate the skin, it would taste or smell something repulsive and fly away.”

Scientists have been trying to figure out the anatomy of the mosquito bite for decades. It’s a job made difficult by the challenge of dissecting mosquitoes’ delicate mouthparts, which tend to fall apart in the hands of beginners. Choo attributed his dissecting abilities to his experience using chopsticks in his native South Korea. Video, powerful microscopes and genetic analyses have helped researchers figure out how the feeding system works.

A protective sheath called the labium bends back as a mosquito pushes needle-like mouthparts into human skin. (Josh Cassidy/KQED)

When a mosquito pierces the skin, a flexible lip-like sheath called the labium scrolls up and stays outside as she pushes in six needle-like parts that scientists refer to as stylets.

Two of these needles, called maxillae, have tiny teeth. The mosquito uses them to saw through the skin. They’re so sharp you can barely feel the mosquito biting you.

“They’re like drill bits,” said Leal.

Another set of needles, the mandibles, hold tissues apart while the mosquito works.

This illustration shows the six needle-like mouthparts that female mosquitoes use to bite us. They use two maxillae (blue) to saw into the skin and two mandibles (yellow) to hold the tissues apart as they saw. They drool saliva into us with the hypopharynx (green) and suck up blood with the labrum (red). (Teodros Hailye/KQED, based on research by Young-Moo Choo and colleagues)

In 2012, scientists at the Pasteur Institute in France filmed what happened once a mosquito proboscis had penetrated through mouse skin. The video shows the sharp-tipped labrum needle probing under the mouse’s skin, then piercing a vessel and sucking blood from it.

The labrum is shaped like a gutter. In order to become a straw it actually needs another mouthpart to lay over it. That mouthpart, called the hypopharynx, serves a dual purpose, as it also allows the mosquito to drool saliva into us.

When a female mosquito feeds, she separates the water from the red blood cells and squeezes it out through her rear end to make room for more blood. (Josh Cassidy/KQED)

As a mosquito’s gut fills up with blood, she separates the water in the blood from the red blood cells and squeezes it out through her rear end.

“She does that to concentrate the red blood cells,” said Luckhart. “The red blood cells provide a large protein component.”

By squeezing water out, she can fit five to ten times more blood inside her.

The sixth needle — called the hypopharynx — drips saliva into us which contains chemicals that keep our blood flowing.

“Your blood tends to coagulate immediately upon contact with the air,” said Leal. “They spit some chemicals so the blood doesn’t coagulate.”

The common house mosquito in California (Culex pipiens) can transmit West Nile virus by biting infected birds, then biting humans. (Josh Cassidy/KQED)

Mosquito saliva also makes our blood vessels dilate, blocks our immune response and lubricates the proboscis. And it causes us to develop itchy welts, and serves as a conduit for dangerous viruses and parasites.

“Infected mosquitoes spit highly variable doses, anywhere from one infectious virion to 10,000,” said UC Davis virologist Lark Coffey, referring to virus particles. “The number of virions needed to productively infect mice can be as low as one. In theory, one might be enough to cause diseases like dengue or West Nile.”

It only takes eight to 20 early-stage malaria organisms to cause the disease.

“Within 20 minutes they make it to the human liver,” said Luckhart. “It’s a very fast process.”

The results of that speedy delivery are deadly. Malaria sickened more than 300 million people in 2015, and killed roughly 635,000, mostly children under the age of five and pregnant women in sub-Saharan Africa.

“It’s probably an underestimate,” said UC Davis medical entomologist Gregory Lanzaro, “because reporting is terrible.”

Dengue fever, a disease transmitted by striped black and white mosquitoes called Aedes aegypti, is estimated to make almost 400 million people sick with jabbing joint pain each year, including a recent outbreak in Hawaii that sickened 260.

Aedes aegypti mosquitoes transmit the viruses that cause Zika and dengue. They bite during the day and can lay their eggs in as little as a bottle cap full of water. (Josh Cassidy/KQED)

Scientists also believe that Aedes aegypti mosquitoes are the main culprit for more than 350 confirmed cases of congenital malformations associated with the Zika virus in the northeastern Brazilian state of Pernambuco. Since last October, an unusually high number of babies have been born there with small heads and a host of health problems like convulsions and persistent crying suspected of being caused by a Zika virus infection early in their mother’s pregnancy.

“We don’t yet know these babies’ life expectancy,” said Dr. Regina Ramos, who cares for these babies at the University of Pernambuco’s Oswaldo Cruz Hospital and participated via Skype in a symposium on Zika at UC Davis on May 26.

Aedes aegypti mosquitoes arrived in California in 2013, to the town of Clovis, near Fresno, and they’ve since been found in pockets throughout California, including Hayward and San Mateo. No locally transmitted cases of Zika have occurred in the continental U.S., though three babies with malformations associated to the virus have been born to mothers who contracted the disease elsewhere.

Mosquitoes don’t get anything out of making us sick ― they just incidentally pass germs onto us. In fact, researchers have found that some viruses started out as mosquito-only viruses. This isn’t hard to believe, as mosquitoes developed 200 million years before humans.

“As mosquitoes evolved the habit of drinking blood, some viruses have tracked that evolutionary path and become human-vectored viruses,” said microbiologist Shannon Bennett, chief of science at the California Academy of Sciences.

How Mosquitoes Use Six Needles to Suck Your Blood

Seen up close, the anatomy of a mosquito bite is terrifying. The most dangerous animal in the world uses six needle-like mouthparts to saw into our skin, tap a blood vessel and sometimes leave a dangerous parting gift.

Posted by Deep Look • PBS on Thursday, July 12, 2018

This entry was posted in SCI & TECH, Videos.

New Self-Healing Concrete Uses Fungus To Fix Cracks

Posted on July 7, 2018

USING FUNGI TO FIX BRIDGES

Assistant professor Congrui Jin (center) with two Binghamton University graduate students from the Mechanical Engineering Department. Image Credit: Jonathan Cohen.

Binghamton University researchers have been working on a self-healing concrete that uses a specific type of fungi as a healing agent.

[youtube https://www.youtube.com/watch?v=IC88GhAiXgk?showinfo=1&controls=1&modestbranding=1&portrait=0&rel=0&enablejsapi=1&origin=https:%2F%2Fwww.binghamton.edu]

America’s crumbling infrastructure has been a topic of ongoing discussion in political debates and campaign rallies. The problem of aging bridges and increasingly dangerous roads is one that has been well documented and there seems to be a consensus from both democrats and republicans that something must be done.

However, spending on infrastructure improvement has continually gone down. The New York Times reported in 2016, based on a report for the Bureau of Economic Analysis, that “in the 1950s and ’60s, federal, state and local governments were spending twice as much on the nation’s public infrastructure, relative to the size of the economy, as they are today.”

The hesitancy to invest in America’s infrastructure may come from a number of sources, but the fact remains that most want something to be done before the consequences are too severe.

Binghamton University assistant professor Congrui Jin has been working on this problem since 2013, and recently published her paper “Interactions of fungi with concrete: significant importance for bio-based self-healing concrete” in the academic journal Construction & Building Materials.

This research is the first application of fungi for self-healing concrete, a low-cost, pollution-free and sustainable approach.

New Self-Healing Concrete Uses Fungus To Fix Cracks

New self-healing concrete uses fungus to fix cracks.

Posted by Hashem Al-Ghaili on Thursday, July 5, 2018

Why is infrastructure crumbling?

Jin’s studies have looked specifically at concrete and found that the problem stems from the smallest of cracks in the concrete.

“Without proper treatment, cracks tend to progress further and eventually require costly repair,” said Jin. “If micro-cracks expand and reach the steel reinforcement, not only the concrete will be attacked, but also the reinforcement will be corroded, as it is exposed to water, oxygen, possibly CO2 and chlorides, leading to structural failure.”

These cracks can cause huge and sometimes unseen problems for infrastructure. One potentially critical example is the case of nuclear power plants that may use concrete for radiation shielding.

What can be done?

While remaking a structure would replace the aging concrete, this would only be a short-term fix until more cracks again spring up. Jin wanted to see if there was a way to fix the concrete permanently.

“This idea was originally inspired by the miraculous ability of the human body to heal itself of cuts, bruises and broken bones,” said Jin. “For the damaged skins and tissues, the host will take in nutrients that can produce new substitutes to heal the damaged parts.”

Jin worked with associate professor Ning Zhang from Rutgers University, and professor Guangwen Zhou and associate professor David Davies from Binghamton University with support from the Research Foundation for the State University of New York’s Sustainable Community Transdisciplinary Area of Excellence Program. Together, the team set out to find a way to heal concrete.

The team found an unusual answer, a fungus called Trichoderma reesei.

When this fungus is mixed with concrete, it originally lies dormant — until the first crack appears.

“The fungal spores, together with nutrients, will be placed into the concrete matrix during the mixing process. When cracking occurs, water and oxygen will find their way in. With enough water and oxygen, the dormant fungal spores will germinate, grow and precipitate calcium carbonate to heal the cracks,” explained Jin.

“When the cracks are completely filled and ultimately no more water or oxygen can enter inside, the fungi will again form spores. As the environmental conditions become favorable in later stages, the spores could be wakened again.”

The research is still in fairly early stages with the biggest issue being the survivability of the fungus within the harsh environment of concrete. However, Jin is hopeful that with further adjustments the Trichoderma reesei will be able to effectively fill the cracks.

“There are still significant challenges to bring an efficient self-healing product to the concrete market. In my opinion, further investigation in alternative microorganisms such as fungi and yeasts for the application of self-healing concrete becomes of great potential importance,” said Jin

This entry was posted in SCI & TECH, Science, Videos.

Market Week Ahead: Top 10 factors that will keep traders busy next week

Posted on July 2, 2018

Volatility in the rupee and prices of crude oil, carnage in midcaps and smallcaps, and trade tensions between US and China resulted in a lot of selling pressure in the week gone by

Source: Moneycontrol News@moneycontrolcom

The market corrected by close to a percent this past week, but thanks to Friday’s rally of over one percent on value buying at lower levels, the losses were greatly minimised.

Volatility in the rupee and prices of crude oil, carnage in midcap and smallcap stocks and trade tensions between US and China resulted in a lot of selling pressure.

Broader markets continued to see sharp correction for the second consecutive week, despite recovering on the last day of the quarter, with the Nifty Midcap and BSE Smallcap indices falling 2.2 percent and 3 percent, respectively.

Both indices crashed 14 percent and 16.6 percent in first half of 2018, which was expected after their stellar rally in 2017. This year, they have underperformed the Nifty and Sensex, which gained 1.7 percent and 4 percent, respectively.

Bears continued to dominate Dalal Street, and their pressure looks like it is here to stay this coming week. Experts said that volatile trade too will remain in the week to come, adding that the focus would slowly shift from global cues to June quarter earnings, which will kick off in the second week of July.

“Nervousness in the market is expected to continue on negative global clues and we will see key indices trading in tight range for the next couple of weeks,” Gaurav Jain, Director at Hem Securities, told Moneycontrol.

Jain said rising fears of a trade war, higher crude prices, and tightening of economies across the globe have hurt the economy and market sentiment. “With no significant events in the coming week, global clues will continue to dominate trading sentiments and stock-specific approach will continue,” he said.

Rajeev Srivastava, Business Head – Securities and Commodities, Reliance Securities, told Moneycontrol that in the backdrop of higher fuel prices, higher interest rate and a weakening rupee scenario, the market may trade in a range and is unlikely to witness any strong appreciation in the next 6-8 months.

He advises investors to invest in quality stocks, which are less vulnerable to macro concerns and have healthy cash flow visibility.

Considering the likely pickup of rural consumption, corporate capital expenditure in the consequence of higher utilisation and recent reforms, Jain is hopeful that corporate earnings will witness double digit growth in coming quarters.

Here are 10 key factors that will keep traders busy next week:

Rupee

The Indian rupee hit an all-time low of 69.09 against the dollar during the week because of higher crude oil prices and strong demand from exporters and banks. It managed to recover 62 paise from the lowest level but failed to end the week on a positive note, ending 0.93 percent weaker at 68.47.

The domestic currency fell for the third consecutive month against the dollar in June and corrected 5 percent in the first quarter of FY19, the biggest quarterly fall since September 2013.

Multiple headwinds like a strong dollar, higher crude prices and concerns related to inflation and fiscal slippage dented sentiment, but interim Finance Minister Piyush Goyal has said that there is no need for a knee jerk reaction to the volatility.

“Rising oil prices, political risk in a pre-election year, low equity risk premia pointing towards relative high valuation and tightening financial conditions in the domestic economy are the major factors which is specifically hurting the rupee,” Anindya Banerjee of Kotak Securities told Moneycontrol.

He said a strong US economy is prompting the US Federal Reserve to tighten monetary policy, and fears of a trade war are affecting most emerging markets were therefore, not a rupee-specific risk.

As a result, carry trade, which is the biggest force driving currency markets, especially EM currencies, is on reverse gear for the rupee in 2018, Banerjee said.

Crude

After the announcement of an increase in supply by OPEC and its allies at their recent meeting, crude oil prices corrected sharply from a three-and-a-half-year high of $80.50 a barrel to around $73 a barrel, but rebounded towards $80 due to unplanned disruption in Canada, Libya and Venezuela.

Another reason why investors were worried were the US’ sanctions on Iran, the fifth largest oil producer in the world, which would reduce a big volume of crude from world markets at a time when demand is rising.

Brent crude futures, the benchmark for international oil prices, jumped 5 percent to $79.44 a dollar during the week.

“As India is the world’s third-largest oil consumer after US and China, with more than 80 percent of its oil demand met through imports, the soaring oil price environment will doubtlessly impact the Indian economy,” CD Equisearch said.

The research firm said market analysts believe that OPEC and its partners could choose to fill up the shortfall created by stress on oil production in Venezuela, Angola and Iran.

“Several countries that are a part of the deal have excess capacity to increase production. US oil producers will also seek to take advantage of the decrease in global oil production but may be confined due to infrastructure bottlenecks and paucity of demand for the extra light grade oil produced by them,” it said.

Auto Sales Data

Auto companies will release their June sales data on July 1 and July 2. So the stock reaction is likely on the coming Monday.

Maruti Suzuki, Tata Motors, TVS Motor, Ashok Leyland, Hero MotoCorp, Bajaj Auto, Eicher Motors, Escorts etc will be in focus.

“Interaction with leading channel partners indicates moderation in retail sales across segments, particularly in rural areas. This can largely be attributed to weak sentiment due to low farm realisations, a delay in the onset of monsoon, and lower crop disbursement by financial institutions,” Motilal Oswal said.

Motilal Oswal Expectations for June sales

Macro Data

Nikkei Manufacturing PMI for June will be released on Monday, followed by Services PMI for the same month on Wednesday.

Foreign Exchange Reserves data for the week ended June 29 will be announced on Friday. Deposit and bad loan growth numbers for the week ended June 22 will also be declared on same day.

Technical Outlook

The Nifty closed the June series below 10,600 levels on Thursday but managed to end the week above 10,700 due to sharp rally on Friday. It was a good start to the July series but bears retained their dominance at Dalal Street as the index lost a percent. Even the Midcap and Smallcap indices failed to get support from bulls as they lost 2-3 percent in a week despite recovery on Friday.

Rangebound move is likely to continue in the coming week and the crucial levels are around 10,550 on the downside and 10,850 on the upside, experts said.

“Index fell sharply from the higher levels and breached the intermediate support of 10,700. Friday’s recovery was quite strong and pulled the index back above 10,700 mark; however it has not damaged the bearish setup. If you got excited about bounce then we think it was a counter trend rise and not a fresh rally. Like we said earlier, bullish possibilities will open up only on a close above 10,900,” Gajendra Prabu, Technical Research Analyst, HDFC Securities told Moneycontrol.

Shabbir Kayyumi, Head – Technical & Derivative Research, Narnolia Financial Advisors said medium term view of range bound movement remains intact as long as indices trade above 10,550. “Nifty RSI near 50 marks also suggests sideways move in coming trading session. Confluences of Fibonacci retracement and 100 EMA round 10,570 levels imply robust support and Nifty will remain strong till it holds above this level.”

Downward sloping trend line connecting previous two major top of 11,121 and 10,929 suggests resistance at 10,850, he added. “Regression line is flat around 10750. We expect sideways movement for next few trading session. On the flip side, Nifty has to close below 10,550 to change this sideways movement thesis.”

Listings

Chemical manufacturer Fine Organic Industries is set to debut on bourses on Monday. The final offer price is fixed at 783 per share. The Rs 600-crore initial public offer was oversubscribed by 8.99 times during June 20-22.

After stellar response to the Rs 466-crore IPO, railways consultancy firm RITES is also going to list its equity shares on same day. The company after consultation with book running lead managers has fixed final issue price at Rs 185 per share. The IPO had garnered strong investor demand, with the issue getting oversubscribed 67.24 times during June 20-22.

Corporate Action

Stocks in Focus

GVK Power: Company initiated the process to monetise its airport assets. Sources told CNBC-TV18 that Paris-based ADP, Singapore’S Changi, Candian Pension Fund and Private Equity Players may be interested in picking up stake.

IDBI Bank: The IRDAI board is likely to have discussed allowing LIC to buy controlling stake in IDBI Bank. Government sources say they will move a cabinet note only after all the regulatory approvals are in place, reports CNBC-TV18. Also former SBI MD B Sriram assumed charge as MD & CEO of the bank effective June 30.

Tata Steel: Company and Thyssenkrupp signed a definitive agreement to create a new European steel champion.

NMDC: Company & Kopano Logistics Services established a 50:50 joint venture company, Kopano-NMDC Minerals to undertake exploration & development of mineral properties in South Africa.

Cadila Healthcare: Zydus gets final approval from US FDA for Triamterene & Hydrochlorothiazide tablets USP.

TCS: Promoter and promoter group of company have communicated their intention to participate in a Rs 16,000 crore share buyback.

HDFC Bank: Managing Director, Aditya Puri told CNBC-TV18 that the bank has no plans to increase foreign branches at this point.

Bank of Maharashtra: MD & CEO RP Marathe & ED RK Gupta divested of functional responsibilties.

Reliance Industries: Company has signed an agreement to acquire US-based open telecom solutions provider Radisys for $1.72 per share in cash. The acquisition is aimed at accelerating Jio’s innovation and technology position in the areas of 5G, IOT and open source architecture adoption.

Viceroy Hotels: As part of the Resolution Process, the Resolution Professional has issued Form G to prospective resolution applicants to submit resolution plan for the company.

Shree Renuka Sugars: After completion of the open offer by Wilmar Sugar Holdings Pte. Ltd, Narendra Murkumbi has stepped-down as the Vice Chairman & Managing Director of the company. He will continue as non-executive director of the company.

Udaipur Cement Works: Approved a project at a capital outlay of Rs 37.50 crore at company’s plant for captive use, and also approved obtaining omnibus approval for raising of funds by way of issue of non-convertible debentures (NCDs) of upto Rs 200 crore at the forthcoming Annual General Meeting.

Parsvnath Developers: Brickwork has re-affirmed the rating ‘B’, assigned to Rs 360 crore non-convertible debentures (Series A) and Rs 244.39 crore non-convertible debentures (Series B) of subsidiary Parsvnath Rail Land Project.

Gujarat Lease Financing: Board has approved the merger of GLFL subsidiaries with GLFL.

Indian Metals & Ferro Alloys: The agitation has been called off with immediate effect. However there would be a loss of around 500 tonnes of ferro chrome production.

Salzer Electronics: Company to acquire two overseas companies – Advanced ID Asia Engineering, Thailand and United Marketing and Trading Limited, Hong Kong.

Welspun Enterprises has received provisional certificate for commercial operation of the Deihi-Meerut Expressway Package-Ol w.e.f. June 28.

Ujaas Energy: CRISIL assigned BBB+/Negative (downgraded from A-/Stable) rating for long term bank loan facilities and A2 (downgraded from A2+) rating for short term bank loan facilities.

Bharat Financial Inclusion completed the second securitisation transaction of Rs 815.75 crore in FY19. With this transaction, the company has completed two securitisation transactions worth Rs 1,365.82 crore in FY19.

Oriental Bank of Commerce has revised base rate from 9.45 percent per annum to 9.50 percent per annum w.e.f. 30.06.2018.

TCS board to consider financial results and interim dividend on July 10

Thermax has concluded an order of Rs 340 crore from a leading Indian steel manufacturer for a specially designed boiler, electric turbo generators and ancillary equipment for their production facility in Maharashtra.

Adani Transmission: Maharashtra Electricity Regulatory Commission approves acquisition of Reliance Infra’s Integrated Business of Generation, Transmission, Distribution and retail of power for Mumbai City by Adani Transmission.

Amber Enterprises: Company has extended the timeline to complete the acquisition of balance stake in Ever Electronics of 51 percent by December 31, 2018 in one or more tranches.

Bosch: Holding company Robert Bosch GmbH plans to sell the packaging machinery business.

Borosil Glass Works: ICRA has placed the long-term rating of A+ and the short-term rating of A1+ assigned earlier to Rs 40 crore Line of Credit on rating watch with developing implications.

Dilip Buildcon: Three wholly owned subsidiary companies have received the sanction letter from NBFC and Nationalized Bank to finance their Hybrid Annuity Mode (HAM) projects. Company is in advance stage to get the sanction for the remaining HAM projects to achieve the financial closure within the specified time period of the Concession agreement.

Esha Media Research has signed an agreement with Limelight networks, Inc, Tempe, AZ. USA.

Mayur Uniquoters: Guman Mal Jain, Chief Financial Officer has resigned due to some personal reason.

Punjab National Bank sold entire stake of 3,30,000 shares of ICRA through block deal at exchange platform for gross sale consideration of Rs 108.60 crore on June 28.

The New India Assurance Company board approved the allotment of bonus shares in the ratio 1:1

Global Cues

Japan’s Nikkei Manufacturing PMI and Foreign Exchange Reserve for June, China’s Caixin Manufacturing PMI for June, Europe’s Manufacturing PMI for June and Unemployment Rate for May, and US Manufacturing PMI for June will be released on Monday.

On Tuesday, US Factory Orders and Euro Area Retail Sales data for the month of May will be announced.

On Wednesday, US Auto Sales for June, China’s Caixin Composite and Services PMI for June, Japan’s Nikkei Services PMI for June and Europe’s Composite and Services PMI for June will be released.

US’ FOMC Minutes, Initial Jobless Claims for the week ended June 30, ADP Employment Change for June, Non Manufacturing PMI for June and Composite and Services PMI for June will be announced on Thursday. Europe’s Retail PMI for June will be released on the same day.

The US Balance of Trade for May, US Non-Farm Payrolls and Unemployment Rate for June, and Japan’s Household Spending for May will be declared on Friday.

This entry was posted in Market.

Can bacteria-slaying viruses defeat antibiotic-resistant infections?

Posted on June 30, 2018

Phages like these studding an *Escherichia coli* bacterium target specific bacteria, complicating their use in medicine.

EYE OF SCIENCE/SCIENCE SOURCE

Can bacteria-slaying viruses defeat antibiotic-resistant infections? A new U.S. clinical center aims to find out

One piece of good news can make all the difference. In the fight against antibiotic-resistant infections, a decades-old approach based on bacteria-slaying viruses called phages has been sidelined by technical hurdles, dogged by regulatory confusion, and largely ignored by drug developers in the West. But 2 years ago, researchers at the University of California, San Diego (UCSD), used phages to knock out an infection that nearly killed a colleague. Propelled by that success and a handful of others since, UCSD is now launching a clinical center to refine phage treatments and help companies bring them to market.

A first in North America, the center will initially consist of 16 UCSD researchers and physicians. It aims to be a proving ground for a treatment that has long been available in parts of Eastern Europe, but that still lacks the support of rigorous clinical trials. “There have been just a ton of failures and false starts,” says Paul Bollyky, a microbiologist and physician at Stanford University Medical Center in Palo Alto, California, who studies phages. “The fact that a major American medical center is going to set up an ongoing enterprise around phage therapy … that’s kind of a game changer for the field, at least in the United States.”

Turning phages—found in soil, water, and sewage—into treatments isn’t straightforward. Because each of the millions of phage strains in nature targets a specific bacterium, putting them to use means finding the specific phages that attack the menace at hand. Still, clinical centers overseas, in Georgia and Poland, have reported encouraging results with phages over the years. And the rise of antibiotic-resistant infections has prompted a handful of U.S. companies and research centers to reconsider the approach.

The case that mobilized the UCSD team hit close to home. In 2015, UCSD psychologist Tom Patterson was airlifted home after a vacation in Egypt when a drug-resistant strain of the bacterium Acinetobacter baumannii invaded his pancreas. As available antibiotics failed and Patterson fell into a coma, his wife, UCSD epidemiologist Steffanie Strathdee, launched an international effort to find strains of phage that might save him. After treatment with a variety of phages donated by San Diego–based biotech AmpliPhi Biosciences, Texas A&M University, and the U.S. Navy, Patterson made a dramatic recovery.

“Everybody’s been talking about this case,” Bollyky says. “Not only did he survive the treatment, which can’t be taken for granted, but he also got better, and miraculously so.” Patterson received some of the phages intravenously—an approach considered risky because toxins from bacteria used to grow the phages could linger in the mixture. His recovery helped allay safety fears, and it turned Strathdee into a self-described “phage wrangler,” who helped match other patients with the right mixture of experimental phages. Since her husband’s recovery, the UCSD team has successfully cleared infections in five more people with phage cocktails, under a U.S. Food and Drug Administration (FDA) process designed for emergencies where no approved treatments are available.

But a string of anecdotes does little to answer key scientific questions: What is the safest and most effective way to administer phages? How well do phages target the site of infection? How quickly are bacteria likely to develop resistance? “Those are the kinds of things you have to ask in structured clinical trials,” says Robert Schooley, a UCSD physician and infectious disease researcher who treated Patterson and oversaw the other recent cases.

So he and Strathdee proposed the new clinical center, which will launch with a 3-year, $1.2 million grant from UCSD. The Center for Innovative Phage Applications and Therapeutics (IPATH) won’t manufacture any phage treatments itself, but it will collaborate with companies and academic groups outside UCSD on multicenter clinical trials. IPATH will initially focus on treating patients with chronic, drug-resistant infections related to organ transplants, implanted devices such as pacemakers or joint replacements, and cystic fibrosis. Schooley is discussing possible trials with a team at the National Institute of Allergy and Infectious Diseases, and with two companies that have provided phages to patients at UCSD: AmpliPhi and Adaptive Phage Therapeutics (APT), based in Gaithersburg, Maryland, which has licensed the Navy’s phage collection.

Running phages through modern clinical testing has proved difficult in the past. A European Union–sponsored trial known as PhagoBurn was all but derailed by a series of setbacks. “It was not an ideal trial, let me say it like that,” says Jean-Paul Pirnay, a bioengineer at Queen Astrid Military Hospital in Brussels, one of the partners in PhagoBurn. A key obstacle was the fact that the trial targeted burn wounds, which often harbor multiple bacterial infections. That made it hard to test the effects of a phage therapy aimed at just one species. Designed to include 220 patients, the trial ultimately recruited only 27, and it has not yet published its results.

The anticipated trials at UCSD, on the other hand, will focus on patients with a single, known bacterial infection, Schooley says. But he admits it will still be tricky to design trials that isolate the effect of phages without withholding other potentially beneficial treatments, including antibiotics. (Ultimately, Schooley and many others expect phages to work in tandem with antibiotics—not to replace them.)

IPATH collaborators will also have to navigate a drug approval system suited to more conventional treatments. Because a phage cocktail will often have to be custom-designed for an individual, regulatory agencies may not have a single product to evaluate for safety and efficacy. But after initial talks with FDA, Greg Merril, APT’s CEO, is confident the agency will be flexible. He plans to seek approval for an entire library of phages—about 100 for each bacterial species—from which doctors could create a cocktail of one to five phages for a patient.

In the meantime, Strathdee says the UCSD team plans to keep securing phages for individual cases under FDA’s emergency pathway. She and Schooley already get several inquiries a week from patients and families fighting drug-resistant infections. “We hope to not send people with superbugs away, but to welcome them with open arms,” she says. “Right now, they don’t have anywhere to go.”

Pirnay, whose team finds and formulates phages to treat infections related to battlefield injuries, has a piece of advice for the UCSD group: “Be careful not to create too high an expectancy with the public,” he says. “Even when you do not say that you will be able to treat everything, you create a demand with desperate patients.”

This entry was posted in SCI & TECH, Science.

Voyage into the world of atoms

Posted on June 30, 2018

This animation shows the structure of matter at smaller and smaller scales. Zooming into a human hair, we pass through hair cells, fibril structures, keratin molecules, carbon atoms, nuclei, neutrons, protons, and finally quarks.

The Standard Model explains how the basic building blocks of matter interact, governed by four fundamental forces. Find out more: http://home.cern/…/physi…/standard-model

Voyage into the world of atoms

This animation shows the structure of matter at smaller and smaller scales. Zooming into a human hair, we pass through hair cells, fibril structures, keratin molecules, carbon atoms, nuclei, neutrons, protons, and finally quarks.The Standard Model explains how the basic building blocks of matter interact, governed by four fundamental forces. Find out more: http://home.cern/about/physics/standard-modelVideo: Daniel Dominguez/CERN

Posted by CERN on Sunday, April 15, 2018

This entry was posted in SCI & TECH, Science, Videos.

Physicists confirm the discovery of fifth force of nature

Posted on June 25, 2018

UCI physicists confirm possible discovery of fifth force of nature

Light particle could be key to understanding dark matter in universe

“If true, it’s revolutionary,” said Jonathan Feng, professor of physics & astronomy. “For decades, we’ve known of four fundamental forces: gravitation, electromagnetism, and the strong and weak nuclear forces. If confirmed by further experiments, this discovery of a possible fifth force would completely change our understanding of the universe, with consequences for the unification of forces and dark matter.”

The UCI researchers came upon a mid-2015 study by experimental nuclear physicists at the Hungarian Academy of Sciences who were searching for “dark photons,” particles that would signify unseen dark matter, which physicists say makes up about 85 percent of the universe’s mass. The Hungarians’ work uncovered a radioactive decay anomaly that points to the existence of a light particle just 30 times heavier than an electron.

“The experimentalists weren’t able to claim that it was a new force,” Feng said. “They simply saw an excess of events that indicated a new particle, but it was not clear to them whether it was a matter particle or a force-carrying particle.”

The UCI group studied the Hungarian researchers’ data as well as all other previous experiments in this area and showed that the evidence strongly disfavors both matter particles and dark photons. They proposed a new theory, however, that synthesizes all existing data and determined that the discovery could indicate a fifth fundamental force. Their initial analysis was published in late April on the public arXiv online server, and a follow-up paper amplifying the conclusions of the first work was released Friday on the same website.

The UCI work demonstrates that instead of being a dark photon, the particle may be a “protophobic X boson.” While the normal electric force acts on electrons and protons, this newfound boson interacts only with electrons and neutrons – and at an extremely limited range. Analysis co-author Timothy Tait, professor of physics & astronomy, said, “There’s no other boson that we’ve observed that has this same characteristic. Sometimes we also just call it the ‘X boson,’ where ‘X’ means unknown.”

Feng noted that further experiments are crucial. “The particle is not very heavy, and laboratories have had the energies required to make it since the ’50s and ’60s,” he said. “But the reason it’s been hard to find is that its interactions are very feeble. That said, because the new particle is so light, there are many experimental groups working in small labs around the world that can follow up the initial claims, now that they know where to look.”

Like many scientific breakthroughs, this one opens entirely new fields of inquiry.

One direction that intrigues Feng is the possibility that this potential fifth force might be joined to the electromagnetic and strong and weak nuclear forces as “manifestations of one grander, more fundamental force.”

Citing physicists’ understanding of the standard model, Feng speculated that there may also be a separate dark sector with its own matter and forces. “It’s possible that these two sectors talk to each other and interact with one another through somewhat veiled but fundamental interactions,” he said. “This dark sector force may manifest itself as this protophobic force we’re seeing as a result of the Hungarian experiment. In a broader sense, it fits in with our original research to understand the nature of dark matter.”

About the University of California, Irvine: Founded in 1965, UCI is the youngest member of the prestigious Association of American Universities. The campus has produced three Nobel laureates and is known for its academic achievement, premier research, innovation and anteater mascot. Led by Chancellor Howard Gillman, UCI has more than 30,000 students and offers 192 degree programs. It’s located in one of the world’s safest and most economically vibrant communities and is Orange County’s second-largest employer, contributing $5 billion annually to the local economy. For more on UCI, visit www.uci.edu.

Media access: Radio programs/stations may, for a fee, use an on-campus ISDN line to interview UCI faculty and experts, subject to availability and university approval. For more UCI news, visit news.uci.edu. Additional resources for journalists may be found at communications.uci.edu/for-journalists.

Physicists confirm the discovery of fifth force of nature

Physicists confirm the discovery of fifth force of nature.

Posted by Hashem Al-Ghaili on Wednesday, June 13, 2018

This entry was posted in SCI & TECH, Science, Videos.

Compound made inside human body stops viruses from replicating

Posted on June 23, 2018

Date: June 20, 2018
Source: Penn State

Summary:: A team of researchers has identified the mode of action of viperin, a naturally occurring enzyme in humans and other mammals that is known to have antiviral effects on viruses such as West Nile, hepatitis C, rabies, and HIV. This discovery could allow researchers to develop a drug that could act as a broad-spectrum therapy for a range of viruses, including Zika.

FULL STORY

: A structural model of viperin a naturally occurring enzyme in humans that is known to have antiviral effects on viruses such as West Nile, hepatitis C, rabies, and HIV. A new study led by researchers from Penn State and the Albert Einstein College of Medicine reveals the mode of action of viperin, which facilitates an important reaction that results in the production of ddhCTP, a molecule that prevents viruses from copying their genetic material.
Credit: David W. Gohara, Ph.D

The newest antiviral drugs could take advantage of a compound made not by humans, but inside them. A team of researchers has identified the mode of action of viperin, a naturally occurring enzyme in humans and other mammals that is known to have antiviral effects on a wide variety of viruses, including West Nile, hepatitis C, rabies, and HIV.

The enzyme facilitates a reaction that produces the molecule ddhCTP, which prevents viruses from copying their genetic material and thus from multiplying. This discovery could allow researchers to develop a drug that induces the human body to produce this molecule and could act as a broad-spectrum therapy for a range of viruses. A paper describing the study appears online on June 20th in the journal Nature.

“We knew viperin had broad antiviral effects through some sort of enzymatic activity, but other antivirals use a different method to stop viruses,” said Craig Cameron, professor and holder of the Eberly Chair in Biochemistry and Molecular Biology at Penn State and an author of the study. “Our collaborators at the Albert Einstein College of Medicine, led by senior authors Tyler Grove and Steven Almo, revealed that viperin catalyzes an important reaction that results in the creation of a molecule called ddhCTP. Our team at Penn State then showed the effects of ddhCTP on a virus’s ability to replicate its genetic material. Surprisingly, the molecule acts in a similar manner to drugs that were developed to treat viruses like HIV and hepatitis C. With a better understanding of how viperin prevents viruses from replicating, we hope to be able to design better antivirals.”

A virus typically co-opts the host’s genetic building blocks to copy its own genetic material, incorporating molecules called nucleotides into new strands of RNA. The molecule ddhCTP mimics these nucleotide building blocks and becomes incorporated into the virus’s genome. Once incorporated into a new strand of the virus’s RNA, these “nucleotide analogs” prevent an enzyme called RNA polymerase from adding more nucleotides to the strand, thus preventing the virus from making new copies of its genetic material.

“Long ago, the paradigm was that in order to kill a virus, you had to kill the infected cell,” said Cameron. “Such a paradigm is of no use when the virus infects an essential cell type with limited capacity for replenishment. The development of nucleotide analogs that function without actually killing the infected cell changed everything.”

Most nucleotide analogs on the market are humanmade, but there are often complications with using these synthetic drugs. Because nucleotides are used by many proteins and enzymes of the cell, numerous opportunities exist for analogs to interfere with normal cellular function.

“The major obstacle to developing therapeutically useful antiviral nucleotides is unintended targets,” said Jamie Arnold, associate research professor of biochemistry and molecular biology at Penn State and an author of the paper. “For example, a few years ago we discovered that a nucleotide analog under development for treatment of hepatitis C could interfere with the production of RNA in mitochondria, subcellular organelles important for energy production in the patient’s own cells. That meant people with mitochondrial dysfunction are predisposed to any negative effects of this unintended interference.”

The molecule ddhCTP, however, does not appear to have any unintended targets. The research team suspects that the natural origin of the compound within the human body necessitates that it be nontoxic.

“Unlike many of our current drugs, ddhCTP is encoded by the cells of humans and other mammals,” said Cameron. “We have been synthesizing nucleotide analogs for years, but here we see that nature beat us to the punch and created a nucleotide analog that can deal with a virus in living cells and does not exhibit any toxicity to date. If there’s something out there that’s going to work, nature has probably thought of it first. We just have to find it.”

To verify the effectiveness of ddhCTP, the research team showed that the molecule inhibited the RNA polymerases of dengue virus, West Nile virus and Zika virus, which are all in a group of viruses called flaviviruses. Then they investigated whether the molecule halted replication of Zika virus in living cells.

“The molecule directly inhibited replication of three different strains of Zika virus,” said Joyce Jose, assistant professor of biochemistry and molecular biology at Penn State and an author of the paper. “It was equally effective against the original strain from 1947 as it was against two strains from the recent 2016 outbreak. This is particularly exciting because there are no known treatments for Zika. This study highlights a new avenue of research into natural compounds like ddhCTP that could be used in future treatments.”

Together, these results demonstrate promising antiviral effects of ddhCTP on a variety of flaviviruses. However, the RNA polymerases of human rhinovirus and poliovirus, which are in a group called picornaviruses, were not sensitive to the molecule. The researchers plan to investigate the polymerase structures of these viruses to better understand why flaviviruses are sensitive to ddhCTP while the picornaviruses tested in this study are not. This investigation may also offer insights into how flaviviruses might develop resistance to the molecule.

“Development of resistance to an antiviral agent is always an issue,” said Cameron, “Having some idea of how resistance happens, or being able to prevent it from happening, will be critical if this is to be used as a broad-spectrum therapy.”

Story Source:

Materials provided by Penn State. Note: Content may be edited for style and length.

Journal Reference:

Anthony S. Gizzi, Tyler L. Grove, Jamie J. Arnold, Joyce Jose, Rohit K. Jangra, Scott J. Garforth, Quan Du, Sean M. Cahill, Natalya G. Dulyaninova, James D. Love, Kartik Chandran, Anne R. Bresnick, Craig E. Cameron, Steven C. Almo. A naturally occurring antiviral ribonucleotide encoded by the human genome. Nature, 2018; DOI: 10.1038/s41586-018-0238-4

This entry was posted in SCI & TECH, Science.

13 medical advances that are changing lives

Posted on June 23, 2018

13 Medical Advances That Are Changing Lives

Thirteen medical advances that are changing lives.

Posted by Tech Insider on Friday, June 15, 2018

This entry was posted in SCI & TECH, Videos.

Tripling the energy storage of lithium-ion batteries

Posted on June 17, 2018

Scientists have synthesized a new cathode material from iron fluoride that surpasses the capacity limits of traditional lithium-ion batteries

Date:June 14, 2018
Source:DOE/Brookhaven National Laboratory
Summary:: Scientists have synthesized a new cathode material from iron fluoride that surpasses the capacity limits of traditional lithium-ion batteries.

FULL STORY

Substituting the cathode material with oxygen and cobalt prevents lithium from breaking chemical bonds and preserves the material’s structure. Credit: Brookhaven National Laboratory

As the demand for smartphones, electric vehicles, and renewable energy continues to rise, scientists are searching for ways to improve lithium-ion batteries — the most common type of battery found in home electronics and a promising solution for grid-scale energy storage. Increasing the energy density of lithium-ion batteries could facilitate the development of advanced technologies with long-lasting batteries, as well as the widespread use of wind and solar energy. Now, researchers have made significant progress toward achieving that goal.

A collaboration led by scientists at the University of Maryland (UMD), the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, and the U.S. Army Research Lab have developed and studied a new cathode material that could triple the energy density of lithium-ion battery electrodes. Their research was published on June 13 in Nature Communications.

“Lithium-ion batteries consist of an anode and a cathode,” said Xiulin Fan, a scientist at UMD and one of the lead authors of the paper. “Compared to the large capacity of the commercial graphite anodes used in lithium-ion batteries, the capacity of the cathodes is far more limited. Cathode materials are always the bottleneck for further improving the energy density of lithium-ion batteries.”

Scientists at UMD synthesized a new cathode material, a modified and engineered form of iron trifluoride (FeF3), which is composed of cost-effective and environmentally benign elements — iron and fluorine. Researchers have been interested in using chemical compounds like FeF3 in lithium-ion batteries because they offer inherently higher capacities than traditional cathode materials.

“The materials normally used in lithium-ion batteries are based on intercalation chemistry,” said Enyuan Hu, a chemist at Brookhaven and one of the lead authors of the paper. “This type of chemical reaction is very efficient; however, it only transfers a single electron, so the cathode capacity is limited. Some compounds like FeF3 are capable of transferring multiple electrons through a more complex reaction mechanism, called a conversion reaction.”

Despite FeF3’s potential to increase cathode capacity, the compound has not historically worked well in lithium-ion batteries due to three complications with its conversion reaction: poor energy efficiency (hysteresis), a slow reaction rate, and side reactions that can cause poor cycling life. To overcome these challenges, the scientists added cobalt and oxygen atoms to FeF3 nanorods through a process called chemical substitution. This allowed the scientists to manipulate the reaction pathway and make it more “reversible.”

“When lithium ions are inserted into FeF3, the material is converted to iron and lithium fluoride,” said Sooyeon Hwang, a co-author of the paper and a scientist at Brookhaven’s Center for Functional Nanomaterials (CFN). “However, the reaction is not fully reversible. After substituting with cobalt and oxygen, the main framework of the cathode material is better maintained and the reaction becomes more reversible.”

To investigate the reaction pathway, the scientists conducted multiple experiments at CFN and the National Synchrotron Light Source II (NSLS-II) — two DOE Office of Science User Facilities at Brookhaven.

First at CFN, the researchers used a powerful beam of electrons to look at the FeF3 nanorods at a resolution of 0.1 nanometers — a technique called transmission electron microscopy (TEM). The TEM experiment enabled the researchers to determine the exact size of the nanoparticles in the cathode structure and analyze how the structure changed between different phases of the charge-discharge process. They saw a faster reaction speed for the substituted nanorods.

“TEM is a powerful tool for characterizing materials at very small length scales, and it is also able to investigate the reaction process in real time,” said Dong Su, a scientist at CFN and a co-corresponding author of the study. “However, we can only see a very limited area of the sample using TEM. We needed to rely on the synchrotron techniques at NSLS-II to understand how the whole battery functions.”

At NSLS-II’s X-ray Powder Diffraction (XPD) beamline, scientists directed ultra-bright x-rays through the cathode material. By analyzing how the light scattered, the scientists could “see” additional information about the material’s structure.

“At XPD, we conducted pair distribution function (PDF) measurements, which are capable of detecting local iron orderings over a large volume,” said Jianming Bai, a co-author of the paper and a scientist at NSLS-II. “The PDF analysis on the discharged cathodes clearly revealed that the chemical substitution promotes electrochemical reversibility.”

Combining highly advanced imaging and microscopy techniques at CFN and NSLS-II was a critical step for assessing the functionality of the cathode material.

“We also performed advanced computational approaches based on density functional theory to decipher the reaction mechanism at an atomic scale,” said Xiao Ji, a scientist at UMD and co-author of the paper. “This approach revealed that chemical substitution shifted the reaction to a highly reversible state by reducing the particle size of iron and stabilizing the rocksalt phase.”Scientists at UMD say this research strategy could be applied to other high energy conversion materials, and future studies may use the approach to improve other battery systems.

Story Source:

Materials provided by DOE/Brookhaven National Laboratory. Note: Content may be edited for style and length.

Journal Reference:

Xiulin Fan, Enyuan Hu, Xiao Ji, Yizhou Zhu, Fudong Han, Sooyeon Hwang, Jue Liu, Seongmin Bak, Zhaohui Ma, Tao Gao, Sz-Chian Liou, Jianming Bai, Xiao-Qing Yang, Yifei Mo, Kang Xu, Dong Su, Chunsheng Wang. High energy-density and reversibility of iron fluoride cathode enabled via an intercalation-extrusion reaction. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-04476-2

This entry was posted in SCI & TECH, Tech.

New type of photosynthesis discovered

Posted on June 17, 2018

Date:June 14, 2018

Source:Imperial College London
Summary:: The discovery changes our understanding of the basic mechanism of photosynthesis and should rewrite the textbooks. It will also tailor the way we hunt for alien life and provide insights into how we could engineer more efficient crops that take advantage of longer wavelengths of light.

FULL STORY

Colony of Chroococcidiopsis-like cells where the different colours represent photosynthesis driven by chlorophyll-a (magenta) and chlorophyll-f (yellow). Credit: Dennis Nuernberg

The discovery changes our understanding of the basic mechanism of photosynthesis and should rewrite the textbooks.

It will also tailor the way we hunt for alien life and provide insights into how we could engineer more efficient crops that take advantage of longer wavelengths of light.

The discovery, published today in Science, was led by Imperial College London, supported by the BBSRC, and involved groups from the ANU in Canberra, the CNRS in Paris and Saclay and the CNR in Milan.

The vast majority of life on Earth uses visible red light in the process of photosynthesis, but the new type uses near-infrared light instead. It was detected in a wide range of cyanobacteria (blue-green algae) when they grow in near-infrared light, found in shaded conditions like bacterial mats in Yellowstone and in beach rock in Australia.

As scientists have now discovered, it also occurs in a cupboard fitted with infrared LEDs in Imperial College London.

Photosynthesis beyond the red limit

The standard, near-universal type of photosynthesis uses the green pigment, chlorophyll-a, both to collect light and use its energy to make useful biochemicals and oxygen. The way chlorophyll-a absorbs light means only the energy from red light can be used for photosynthesis.

Since chlorophyll-a is present in all plants, algae and cyanobacteria that we know of, it was considered that the energy of red light set the ‘red limit’ for photosynthesis; that is, the minimum amount of energy needed to do the demanding chemistry that produces oxygen. The red limit is used in astrobiology to judge whether complex life could have evolved on planets in other solar systems.

However, when some cyanobacteria are grown under near-infrared light, the standard chlorophyll-a-containing systems shut down and different systems containing a different kind of chlorophyll, chlorophyll-f, takes over.

Until now, it was thought that chlorophyll-f just harvested the light. The new research shows that instead chlorophyll-f plays the key role in photosynthesis under shaded conditions, using lower-energy infrared light to do the complex chemistry. This is photosynthesis ‘beyond the red limit’.

Lead researcher Professor Bill Rutherford, from the Department of Life Sciences at Imperial, said: “The new form of photosynthesis made us rethink what we thought was possible. It also changes how we understand the key events at the heart of standard photosynthesis. This is textbook changing stuff.”

Preventing damage by light

Another cyanobacterium, Acaryochloris, is already known to do photosynthesis beyond the red limit. However, because it occurs in just this one species, with a very specific habitat, it had been considered a ‘one-off’. Acaryochloris lives underneath a green sea-squirt that shades out most of the visible light leaving just the near-infrared.

The chlorophyll-f based photosynthesis reported today represents a third type of photosynthesis that is widespread. However, it is only used in special infrared-rich shaded conditions; in normal light conditions, the standard red form of photosynthesis is used.

It was thought that light damage would be more severe beyond the red limit, but the new study shows that it is not a problem in stable, shaded environments.

Co-author Dr Andrea Fantuzzi, from the Department of Life Sciences at Imperial, said: “Finding a type of photosynthesis that works beyond the red limit changes our understanding of the energy requirements of photosynthesis. This provides insights into light energy use and into mechanisms that protect the systems against damage by light.”

These insights could be useful for researchers trying to engineer crops to perform more efficient photosynthesis by using a wider range of light. How these cyanobacteria protect themselves from damage caused by variations in the brightness of light could help researchers discover what is feasible to engineer into crop plants.

Textbook-changing insights

More detail could be seen in the new systems than has ever been seen before in the standard chlorophyll-a systems. The chlorophylls often termed ‘accessory’ chlorophylls were actually performing the crucial chemical step, rather than the textbook ‘special pair’ of chlorophylls in the centre of the complex.

This indicates that this pattern holds for the other types of photosynthesis, which would change the textbook view of how the dominant form of photosynthesis works.

Dr Dennis Nürnberg, the first author and initiator of the study, said: “I did not expect that my interest in cyanobacteria and their diverse lifestyles would snowball into a major change in how we understand photosynthesis. It is amazing what is still out there in nature waiting to be discovered.”

Peter Burlinson, lead for frontier bioscience at BBSRC — UKRI says, “This is an important discovery in photosynthesis, a process that plays a crucial role in the biology of the crops that feed the world. Discoveries like this push the boundaries of our understanding of life and Professor Bill Rutherford and the team at Imperial should be congratulated for revealing a new perspective on such a fundamental process.”

Story Source:

Materials provided by Imperial College London. Note: Content may be edited for style and length.

Journal Reference:

Dennis J. Nürnberg, Jennifer Morton, Stefano Santabarbara, Alison Telfer, Pierre Joliot, Laura A. Antonaru, Alexander V. Ruban, Tanai Cardona, Elmars Krausz, Alain Boussac, Andrea Fantuzzi, A. William Rutherford. Photochemistry beyond the red limit in chlorophyll f–containing photosystems. Science, 2018; 360 (6394): 1210 DOI: 10.1126/science.aar8313

This entry was posted in SCI & TECH, Science.

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