AcetylCoA synthase

Three of the eight Ni proteins that are known as hydrogenase, CO dehydrogenase (CODH), and acetylCoA synthase (ACS), are Ni-Fe-S proteins. Hydrogenases play an important role in microbial energy metabolism by catalysing the reversible oxidation of hydrogen ... 

Carbon monoxide dehydrogenase-acetylCoA synthase, models, 8, 124... 

A stoichiometric model system by Holm for the acetylCoA synthase activity of CODH is shown in Eq. 16.41. This reaction is a property of the NiFeC cluster, of unknown structure, present in CODH. The enzyme brings about exchange between CO and Me COCoA, which implies that formation of the C—S and Me—CO bonds is reversible. This is consistent with CO insertion into a Ni—Me bond, and nucleophilic attack on the resulting Ni(COMe), both of which can be reversible. 

Models of the Carbon Monoxide Dehydrogenase - AcetylCoA Synthase (COD/ACS) 124... 

AcetylCoA carboxylase Glycogen synthase HMGCoA reductase NO synthase Biosynthesis of fatty adds Glycogen synthesis Biosynthesis of cholesterol Biosynthesis of NO ... 

This pathway, also located in the mitochondria, generates acetylCoA which is then completely metabolized by the Krebs cycle, the ETS, and ATP synthase. The overall equation for fatty acid oxidation, using palmitate as an example, can be written as ... 

These characteristics of lysine producers are combined to produce much stronger lysine producing strains. In addition to these fundamental properties, further addition of leucine requiring mutation is effective to increase the amount of lysine since in the mutant dihydrodipycolinate synthase is released from repression by leucine. The precursors of lysine synthesis include phosphoenol-pyruvate, pyruvate, and acetylCoA. In addition, many mutations are induced in the lysine producers to supply sufficient amounts of these precursors in good balance. These are deletion mutants of pyruvate kinase and show low activity of pyruvate dehydrogenase, etc. Furthermore, an alanine requirement was also reported to be effective in increasing the lysine amount. 

Fischer, P.W.F. Goodridge, A.G. (1978). Coordinate regulation of acetylCoA carboxylase and fatty add synthase in liver cells of the developing chick in vivo and in culture. Arch. Biophys. Biochem., 190, 332—44. 

Abbreviations (listed alphabetically) l,3bPGA, 1,3-bisphosphoglyceric acid 20G, 2-oxoglutaric acid 3PGA, 3-phosphoglyceric acid acetylCoA, acetyl coenzyme A ADP/ATP, adenosine diphosphate and triphosphate ADPGlu, adenosine diphosphate glucose AOX, alternative oxidase Aqp, aquaporin Ca, atmospheric CO2 Cc, chloroplast CO2 Ci, intercellular CO2 cl, mitochondrial Complex 1 cll, mitochondrial Complex 11 cll, mitochondrial Complex 111 clV, mitochondrial Complex IV (cytochrome oxidase) cV, mitochondrial Complex V (ATP Synthase) citrate, citric acid CoA, coenzyme A E4P,... 

AT = acyl transferase (from acetylCoA to the PKS) ACP = acyl carrier protein KS = keto synthase... 

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