 |
According to a report by the Physicist Organization Network on June 5 (Beijing time), a group of people from Sweden, Germany, and other countries used short-pulse X-ray analysis to see the molecular structure of plants undergoing photosynthesis and found that calcium is in the water decomposition process. China is extremely important and is the key to building artificial photosynthetic systems. This method provides a new way to understand the photosynthesis of photosynthetic plants in nature, the structure and reaction mechanism of photosynthetic systems, and ultimately the realization of artificial photosynthesis. The paper was published in the recently published "Journal of the National Academy of Sciences".
Photosynthesis can be divided into two steps: the first step is light reaction, and sunlight provides energy to decompose water molecules, release oxygen, and supply energy for the next dark reaction; the second step is dark reaction, using the energy of the first step to react with CO2. Produce various carbohydrates. At the photosynthesis center, two different photosynthetic protein complex pigment systems perform two photochemical reactions: photosynthesis system I (PSI) and photosynthetic system II (PSII). Among them, PSII stimulates high-energy electrons during photoreaction, decomposes water molecules, releases oxygen and promotes electron transfer, and initiates the first step of photoreaction. It is very important in this process.
A team led by Johannes Messinger, a professor of chemistry at the University of Ormer in Sweden, tried to develop artificial photosynthesis using the "artificial leaves" project to simulate the use of solar energy by plants. But it must first be clear about which molecules in photosynthesis are essential for the decomposition of water and how these molecules work. For this reason, the team designed a tool to study the photosynthetic system of plants during photosynthesis.
Previous studies have found that the oxygenated complex (Mn4O5Ca) is a component of PSII, and removal of calcium ions results in the inability to release oxygen. The Messinger team isolated the oxygenated complex molecules from the PSII, managed to remove the calcium ions, and then analyzed the molecular structure using ultrashort X-ray pulses emitted by the X-ray free electron laser equipment of the Stanford University. Under the movement of atomic 50 femtoseconds (1 femtosecond = 10-15 seconds).
“The five oxygen atoms in the oxygen release complex unite four manganese ions together. After removing the calcium ions, this structure has not changed, indicating that calcium ions must play an extremely important role in the water decomposition reaction.†Messing Jie explained that because the X-ray pulse used in the experiment is very short, the photosynthetic system will not be disturbed during detection. “Using this new tool, we can finally find out how the oxygen atoms form oxygen bridges and eventually produce oxygen molecules when water is decomposed. It has been impossible to study this stage in detail in the past.†(Reporter Chang Li Jun)
HUATAO GROUP supply the kinds of Spare Parts of Paper Machine from China, Our products incluing Head box on paper machine , Wiper Blade ,Press roll and stone rolls,Section roll and Cyliner mould.
Spare Parts of Paper Machine,Head box on paper machine,Wiper Blade,Press roll and stone rolls,Section roll and Cyliner mould
HUATAO GROUP LTD , http://www.huataogroup.com