Taking the mystery out of photosynthesis

Feb 10, 2011
The team found that manganese (pink) and oxygen (red) form a central column that supports large ligands, made of nitrogen, carbon (gray), and hydrogen (white).

(PhysOrg.com) -- An enigmatic protein system that uses sunlight and water to create fuel became a little less mysterious, thanks to scientists at Pacific Northwest National Laboratory, University of Michigan, and University of California -- Davis.

The photoactive protein known as the oxygen-evolving complex, or OEC, is found in plants and algae and is deeply involved in photosynthesis. Determining the geometric and electronic structures of a model for OEC was done using ultra-cold experimental and first-principle theoretical techniques.

Through photosynthesis, plants and use intermittent to create readily available fuels. Scientists and experts want to design industrial plants to do the same thing. But before this process can be designed and controlled on the large scale, it must be understood on the small scale. Uncovering OEC's structure provides fundamental insights for modeling and simulating the molecule's behavior. With greater confidence in models, scientists can delve more deeply into the process, learning what is needed to mimic the process on the large scale.

To determine the geometric structure and arrangement of electrons in OEC, the researchers brought together experimentation and . They used bis(μ-oxido)dimanganese(IV) complex [Mn2O2(salpn)2] as a model for the manganese-based motifs in OEC. They employed a 55Mn solid-state NMR at cryogenic temperatures. Using this instrument allowed the team to study the molecules with multi-spin sites. Having multiple spin sites is typical of energy materials. The NMR equipment was made available through a user proposal process at EMSL.

Based on the experimental results, the team applied first-principle density functional theory calculations to determine the structure and corresponding NMR parameters. The structure of the material involves a central pillar with manganese and oxygen atoms coordinated by large ligands representing the surrounding protein environment.

This study is part of broader fundamental biomimetic energy research being done at Pacific Northwest National Laboratory, including studies being done at the Energy Frontier Research Center and Institute for Interfacial Catalysis.

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More information: Ellis PD, JA Sears, P Yang, M Dupuis, TT Boron III, VL Pecoraro, TA Stich, RD Britt, and AS Lipton. 2010. "Solid-State 55Mn NMR Spectroscopy of Bis(μ-oxo)dimanganese(IV) [Mn2O2(salpn)2], A Model for the Oxygen Evolving Complex in Photosystem II." Journal of the American Chemical Society 132, 16727-16729. DOI:10.1021/ja1054252

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kevinrtrs
1 / 5 (13) Feb 10, 2011
As I mentioned before: Plants really have the evolutionists running helter skelter to find an explanation for their non-ancestoral lineage.

Here we again have a reminder of the absolute miracle that would be required for plants to evolve spontaneously from nothing - that incredibly complex molecule and the magical cycle of replenishing electrons in photosynthesis just does not submit to the thought of random processes creating it. The molecule refuses to play by those evolutionary rules.

It has so far required very intelligent people many years and a great deal of money to get this far - and they still haven't solved the mystery.
How does anyone expect random processes to have produced photosynthesis? It might be better to believe in the spaghetti monster, surely?
apex01
5 / 5 (7) Feb 10, 2011
I believe in the cookie monster.
Corban
5 / 5 (8) Feb 10, 2011
Random implies that they just flipped a coin, and tried to get 100 heads in a row.

Evolution flips a coin 100 times, but gets to ignore the tails (because they're dead). Thus, the most flips required for 100-in-a-row is not a trillion, but just 200.

Suddenly it all becomes clear.
antialias
5 / 5 (6) Feb 10, 2011
If they want to learn from photosynthesis then they need to be prepared to improve the process a lot. Photosynthesis is, at 3% conversion rate, woefullly inefficient.

P.S.: Don't try to explain anything to kevinrtrs. He only ever posts once and then never returns to the discussion. Ignore the troll
FrankHerbert
2 / 5 (4) Feb 11, 2011
that incredibly complex molecule and the magical cycle of replenishing electrons in photosynthesis just does not submit to the thought of random processes creating it.


It does if you're smart.
PaulieMac
5 / 5 (1) Feb 11, 2011
As I mentioned before: Plants really have the evolutionists running helter skelter to find an explanation for their non-ancestoral lineage.


And as I posted in reponse - your assertion is a lie. For anyone interested in the evolution of plants, I'd suggest the wiki article "Plant_Evolution" as a decent starter, with the references as further light reading.

It might be better to believe in the spaghetti monster


Well, the Flying Spaghetti Monster is as valid a belief as your magic sky fairy. There is certainly an equal amount of evidence to support either!
Donutz
5 / 5 (1) Feb 11, 2011
As I mentioned before: Plants really have the evolutionists running helter skelter to find an explanation for their non-ancestoral lineage.


No they don't, and continually saying it won't make it so.

I notice that you are always always always among the top couple of people posting on any article relating to evolution, and that you almost never post on non-evo-related stuff. So, who's paying you and how much? Or do you just not have a day-job or a life?