HOME >> BIOLOGY >> NEWS
Photosystem I -- An Intermediate Step -- May Not Be Necessary For Plants

ITHACA, N.Y. -- Plant biologists have long held the view that photosynthesis -- the process by which cells in green plants convert the energy of sunlight into chemical energy and use carbon dioxide to produce sugars -- needs two intermediate light-dependent reactions for successful energy conversion: Photosystem II and Photosystem I.

But according to a new study reported today (July 19), that dogma may have gone for a walk, and scientists may have to rethink some aspects of how photosynthesis works. "Scientists have thought they understood photosynthesis for a long time, and this revelation flies in the face of what we know," said Thomas G. Owens, Cornell University associate professor of plant biology. "What does this all mean? No one knows yet."

The Z scheme is the classic example of how scientists describe the light-dependent reactions of photosynthesis. When photons -- particles of light -- enter a plant cell, their energy is used to power two sequential light-dependent reactions. In Photosystem II (PSII), the light energy is used to split water, producing oxygen and electrons. In Photosystem I (PSI), these electrons are used to produce compounds that ultimately react with carbon dioxide to produce carbohydrates, lipids, proteins and nucleic acids -- the fundamental components of life.

But Owens and researchers from the Oak Ridge National Laboratory in Tennessee found that in some cases photosynthesis can occur in the absence of PSI, they report in the journal Science (July 19, 1996). The report, "Oxygenic Photoautotrophic Growth Without Photosystem I," was authored by James W. Lee, C.V. Tevault and Elias Greenbaum, all of the Oak Ridge National Laboratory, and Cornell's Owens.

The scientists from Oak Ridge used artificially developed mutants of a green alga to find this new life process.

"It is a very important discovery; I didn't believe any of this stuff when it was first reported. I thought it was impossible, but cooperation between
'"/>

Contact: Blaine Friedlander
bpf2@cornell.edu
607-255-3290
Cornell University News Service
19-Jul-1996


Page: 1 2

Related biology news :

1. Oxygen-Carrying Myoglobin Not Necessary For Survival
2. Plants will not save us from greenhouse gases
3. Plants for the future: A European vision for plant biotechnology towards 2025
4. Plants circadian clocks tune into latitude to enhance fitness
5. Plants and people share a molecular signaling system, researchers discover
6. Nonnative Invasive Plants of Southern Forests
7. Plants, insects play cat and mouse game
8. Plants vs. disease: Trench warfare at the molecular level
9. Plants as plants: gene could convert crops to plastics factories
10. Plants, pathogens engage in trench warfare
11. Study: Microgravity May Enhance Gene Transfer In Plants

Post Your Comments:
*Name:
*Comment:
*Email:
TAG: Photosystem Intermediate Step May Not Necessary For Plants

(Date:4/17/2014)... If a restaurant ... he can expect his premises to be trashed. Warnings like ... is enough to make restaurant owners pay up. Similarly, mafia-like ... in other birds, nests. If the host birds throw the ... destroying the entire nest. Consequently, it is beneficial for hosts ...
(Date:4/17/2014)... IPCC meeting painted a stark warning on the possible ... a greenhouse effect 32 times that of carbon dioxide. ... humic substances act as fully regenerable electron acceptors which ... in wetlands instead of being released to the atmosphere. ... disrupted it may enter into a vicious cycle to ...
(Date:4/17/2014)... wild animals and plant life, but there,s an invisible ... in the soil, decomposing organic matter and releasing carbon ... fungi play in ecological systems, their identities have only ... generated a genetic map of more than 10,000 species ... this week in the Proceedings of the National ...
Breaking Biology News(10 mins):Fear of the cuckoo mafia 2Fear of the cuckoo mafia 3Methane climate change risk suggested by proof of redox cycling of humic substances 2Stanford biologists help solve fungal mysteries 2Stanford biologists help solve fungal mysteries 3
(Date:1/15/2014)... Hills, IL (PRWEB) January 15, 2014 ... to find hard-working items for the lab, from fluid ... as Guaranteed-in-Stock (GIS)—ready to ship when you order. ... Masterflex® Peristaltic Pumps , from the L/S® model for ...
(Date:1/15/2014)... MINNEAPOLIS , Jan. 15, 2014 ­ RedBrick ... and behavior change technology, today announces that EmblemHealth ... insurer and wellness company, is now providing the RedBrick ... digital coaching program, to all of its members. EmblemHealth ...
(Date:1/15/2014)... 15, 2014 More than 5 million ... 1 in 3 seniors will die with Alzheimer’s or ... jaw-dropping figures have shocked many Americans into looking for ... prevent these tragic age-related cognitive disorders. Jonathan Weisman, president ...
(Date:1/15/2014)... January 15, 2014 DTS Language Services, ... Online Web Portal for Life Science organizations who need document ... the subject matter of their documents in advance with a ... reduce time-to-delivery of translations, often a critical factor in clinical ...
Breaking Biology Technology:Cole-Parmer Begins 2014 with the Release of Preferred Solutions 2EmblemHealth Selects RedBrick Health to Power its Next-Generation Health Engagement and Behavior Change System 2EmblemHealth Selects RedBrick Health to Power its Next-Generation Health Engagement and Behavior Change System 3Biohack Pure Offers 5 Tips for Increasing Memory in 2014 2DTS Improves Efficiency for Life Science Document Translations 2
Cached News: