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The Fe protein, the dinitrogenase reductase or NifH, is a dimer of identical subunits which contains one [Fe 4 S 4] cluster and has a mass of approximately 60-64kDa. [2] The function of the Fe protein is to transfer electrons from a reducing agent, such as ferredoxin or flavodoxin to the nitrogenase protein.
FeMoco (FeMo cofactor) is the primary cofactor of nitrogenase. Nitrogenase is the enzyme that catalyzes the conversion of atmospheric nitrogen molecules N 2 into ammonia (NH 3) through the process known as nitrogen fixation. Because it contains iron and molybdenum, the cofactor is called FeMoco. Its stoichiometry is Fe 7 MoS 9 C.
Nitrogenase is thought to have evolved sometime between 1.5-2.2 billion years ago (Ga), [38] [39] although some isotopic support showing nitrogenase evolution as early as around 3.2 Ga. [40] Nitrogenase appears to have evolved from maturase-like proteins, although the function of the preceding protein is currently unknown.
Abiological nitrogen fixation describes chemical processes that fix (react with) N 2, usually with the goal of generating ammonia. The dominant technology for abiological nitrogen fixation is the Haber process , which uses iron-based heterogeneous catalysts and H 2 to convert N 2 to NH 3 .
A strong focus of her research is to study the enzyme that is responsible for the conversion of dinitrogen (N 2) to ammonia (NH 3)—Nitrogenase. Serena DeBeer and her group study this remarkable system comprising a FeMo cofactor (FeMoco) as its active site, and structural model complexes utilizing high-resolution X-ray absorption (XAS) and X ...
It differs in having an extra amine group, creating a more stable bond to thymine. [3] Adenine and guanine have a fused-ring skeletal structure derived of purine, hence they are called purine bases. [4] The purine nitrogenous bases are characterized by their single amino group (−NH 2), at the C6 carbon in adenine and C2 in guanine. [5]
The iron in cytochromes usually exists in a ferrous (Fe 2+) and a ferric (Fe 3+) state with a ferroxo (Fe 4+) state found in catalytic intermediates. [1] Cytochromes are, thus, capable of performing electron transfer reactions and catalysis by reduction or oxidation of their heme iron. The cellular location of cytochromes depends on their function.
[2] [3] The atoms in molecules, crystals, metals and other forms of matter are held together by chemical bonds, which determine the structure and properties of matter. All bonds can be described by quantum theory, but, in practice, simplified rules and other theories allow chemists to predict the strength, directionality, and polarity of bonds. [4]