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O-succinylbenzoate CoA ligase ((6.2.1.26 )), encoded from the menE gene in ''Escherichia coli'', catalyzes the fifth reaction in the synthesis of menaquinone (vitamin K2). This pathway is called 1, 4-dihydroxy-2-naphthoate biosynthesis I. Vitamin K is a quinone that serves as an electron transporter during anaerobic respiration. This process of anaerobic respiration allows the bacteria to generate the energy required to survive. == Background == The systematic name for the MenE enzyme is 2-succinylbenzoate: CoA ligase (AMP-forming). Other names for this enzyme include: o-succinylbenzoate-CoA synthase; o-succinylbenzoyl-coenzyme A synthetase; OSB-CoA synthetase; OSB: CoA ligase; synthetase, and o-succinylbenzoyle coenzyme A. The EC number is 6.2.1.26. MenE belongs to the ligase enzyme family, or class 6. In the presence of .5mM of Ca(2+), K(+), Na(+), and Zn(2+) the enzyme activity was increased twofold. In the presence of .5 mM of Co(2+) and Mn(2+) the enzyme activity was increased fourfold. Mg(2+) is the ion that increases the enzyme activity the most. With .5 mM of Mg(2+) enzyme activity was increased sixfold. Inhibitors of this enzyme include diethylprocarbonate, Fe(2+), Hg(2+), and Mg(2+) (above 1mM). The maximum specific enzymatic activity is 3.2 micromol/min/mg. The optimum pH is 7.5. The maximum pH is 8. The optimum temperature is 30 degrees Celsius and the maximum temperature is 40 degrees Celsius. The molecular weight of o-succinylbenzoate CoA ligase is 185000 Da or 185 kDa. This enzyme is a tetramer, meaning it has four subunits in its quaternary structure. The PDB accession code is (3ipl ). This is the crystal structure for o-succinylbenzoate CoA ligase in Staphylococcus aureus (strain N315) because the structure for ''E. coli'' has not been crystallized as of yet. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「O-succinylbenzoate—CoA ligase」の詳細全文を読む スポンサード リンク
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