Subscribe free to our newsletters via your
  Solar Energy News  




Subscribe free to our newsletters via your




















SOLAR DAILY
How photosynthetic cells deal with a lack of iron
by Staff Writers
Freiburg, Germany (SPX) May 08, 2017


University of Freiburg researchers discover a small RNA molecule in cyanobacteria that affects metabolic acclimation. Credit: Sandra Meyndt

International researchers working in collaboration with Professor Wolfgang R. Hess and Dr. Jens Georg, both from the University of Freiburg's Faculty of Biology, have discovered a small RNA molecule that plays a key role in how cyanobacteria adjust their metabolism to the amount of iron available in the environment.

Oxygenic photosynthesis - in which plants, algae and cyanobacteria generate oxygen and harvest solar energy for the synthesis of organic matter - is a process that depends on iron. When only low amounts of iron are available, cyanobacteria are able to reduce their photosynthetic activity by using what the researchers are calling IsaR1, which stands for "iron stress activated RNA 1." The team of researchers have published their findings in the latest issue of Current Biology.

As a result of their dependence on iron, oxygen-producing photosynthetic cells face a twofold dilemma. On the one hand, ferric iron (Fe3+) and oxygen tend to react with each other and form a type of rust that is typically insoluble in an oxygen-rich environment, meaning that the resulting iron compound cannot be used for metabolism.

On the other hand, ferrous iron (Fe2+) can lead to the creation of dangerous free radicals by reacting with molecules that are present in every living cell. Iron is therefore an essential but potentially dangerous element, and cells must constantly regulate its status and concentration.

Scientists have known for a long time that many bacteria keep their iron levels stable with the help of a transcription factor called Fur, which stands for "ferric uptake regulator."

When sufficient amounts of iron are present, Fur binds it. This enables Fur to act as a repressor, meaning it is inhibitory for the expression of certain genes. If iron starvation occurs, then Fur loses the bound iron atom, enabling the bacteria to produce certain proteins that, for example, ensure the uptake of iron.

When not enough iron is available, the bacteria also have to inhibit the expression of other genes, so that they can stop the production of proteins that are particularly iron-rich and are not absolutely necessary for survival in unfavorable conditions. This is especially true regarding the apparatus for oxygenic photosynthesis, which is the most iron-rich supramolecular structure in the cell.

The transcription of the information contained in the DNA involves regulatory RNAs. One of these RNA molecules is IsaR1. When iron is low, IsaR1 affects the photosynthetic apparatus of cyanobacteria in three different ways. First, IsaR1 inhibits the expression of multiple proteins that are important for photosynthesis.

Second, IsaR1 interferes with the biochemical pathway leading to the production of the green photosynthetic pigment chlorophyll, which is needed in smaller quantities when iron is scarce. Third, IsaR1 works against the expression of proteins for iron-sulfur clusters, which are also important in photosynthesis.

What is also remarkable is that IsaR1 consists of only 68 nucleotides, as compared to the genes of regulatory proteins, which often need thousands of these building blocks. "Discovering that such a short RNA molecule controls such a major acclimation response in metabolism and thus affects the photosynthetic machinery on three different levels was a great surprise," said Wolfgang Hess.

The team's findings not only provide insight into a previously unknown acclimation strategy of photosynthetic cyanobacteria; they also enable researchers to draw key conclusions about the regulation of photosynthetic processes in all "green" organisms, including plants and algae.

Jens Georg, Gergana Kostova, Linda Vuorijoki, Verena Schon, Taro Kadowaki, Tuomas Huokko, Desiree Baumgartner, Maximilian Muller, Stephan Klahn, Yagut Allahverdiyeva, Yukako Hihara, Matthias E. Futschik, Eva-Mari Aro, Wolfgang R. Hess: Acclimation of Oxygenic Photosynthesis to Iron Starvation Is Controlled by the sRNA IsaR1. Current Biology, DOI 10.1016/j.cub.2017.04.010

SOLAR DAILY
Discovery of new transparent thin film material could improve electronics and solar cells
Minneapolis MN (SPX) May 09, 2017
A team of researchers, led by the University of Minnesota, have discovered a new nano-scale thin film material with the highest-ever conductivity in its class. The new material could lead to smaller, faster, and more powerful electronics, as well as more efficient solar cells. The discovery is being published in Nature Communications, an open access journal that publishes high-quality rese ... read more

Related Links
University of Freiburg
All About Solar Energy at SolarDaily.com

Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

SOLAR DAILY
New breakthrough makes it easier to turn old coffee waste into cleaner biofuels

Enhancing the efficiency of cereal straw for biofuel production

Biomass powering U.S. military base

First EPA-approved outdoor field trial for genetically engineered algae

SOLAR DAILY
Amazon's new Alexa speaker has a screen too

3-D-printed 'bionic skin' could give robots the sense of touch

Computers learn to understand humans better by modelling them

Your future surgery may use an automated, robotic drill

SOLAR DAILY
Dutch open 'world's largest offshore' wind farm

Scientists track porpoises to assess impact of offshore wind farms

OX2 will manage a 45 MW wind farm owned by IKEA Group in Lithuania

Building Energy celebrates the beginning of operations and electricity generation of its first wind farm

SOLAR DAILY
Chinese carmaker Geely to be largest Saxo shareholder

Germany's Bosch sells subsidiary to China's ZMJ

Bike-sharing launched in congested Beirut

Free rides offered by Alphabet's Waymo autonomous cars

SOLAR DAILY
New model of plasma stability could help researchers predict and avoid disruptions

Can the motion of checking your smartwatch charge it?

NRL breakthrough enables safer alternative to lithium-ion batteries

Super P carbon black for reversible lithium and sodium ion storage

SOLAR DAILY
Tunnel collapse at US nuclear site raises safety concerns

Plutonium research to aid nuclear cleanup techniques

EU Plans to Hand Over Control of Euratom Nuclear Waste on UK Soil to London

Tunnel collapses at US nuke site, no radiation leak

SOLAR DAILY
Australia power grid leased to local-foreign consortium

Myanmar recovery linked to development of electrical grid

Poland central to EU energy diversification strategy

U.S. emissions generally lower last year

SOLAR DAILY
Poland EU row over ancient forest heats up

DR Congo arrests 14 Chinese for wood smuggling

DR Congo arrests 14 Chinese for wood smuggling

Long-term fate of tropical forests may not be as dire as believed




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement