Aminomutases

Methylmalonyl CoA mutase, leucine aminomutase, and methionine synthase (Figure 45-14) are vitamin Bj2-dependent enzymes. Methylmalonyl CoA is formed as an intermediate in the catabolism of valine and by the carboxylation of propionyl CoA arising in the catabolism of isoleucine, cholesterol, and, rarely, fatty acids with an odd number of carbon atoms—or directly from propionate, a major product of microbial fer-... 

Studies on three different iron-sulfur enzyme systems, which all require S-adenosyl methionine—lysine 2,3-aminomutase, pyruvate formate lyase and anaerobic ribonucleotide reductase—have led to the identification of SAM as a major source of free radicals in living cells. As in the dehydratases, these systems have a [4Fe-4S] centre chelated by only three cysteines with one accessible coordination site. The cluster is active only in the reduced... 

Timothy J. Montavon was born in Wheelersburg, OH, in 1982. He attended Xavier s University in Cincinnati, OH, where he earned a B.S. in chemistry in 2004. While at Xavier s, he worked in the laboratory of Professor Aaron Baba developing novel fluoroiono-phores. In 2004, he began attending graduate school at Boston College working in the laboratory of Professor Steven Bruner. His current research is focused on the structure and mechanism of aminomutase enzymes used in the biosynthesis of enediyne natural products. 

Cosper NJ, Booker SJ, Ruzicka FJ, et al. 2000. Direct FeS cluster involvement in generation of a radical in lysine 2,3-aminomutase. Biochemistry 39 15668-73. 

LEUCINE 2,3-AMINOMUTASE LEUCINE AMINOTRANSFERASE LEUCINE DEHYDROGENASE LEUCINE KINETICS LEUCYL-tRNA SYNTHETASE ZWITTERION yS-Leucine,... 

LEUCINE 2,3-AMINOMUTASE LEUCINE AMINOPEPTIDASE LEUCINE AMINOTRANSFERASE... 

LYSINE 2,3-AMINOMUTASE LYSINE 6-AMINOTRANSFERASE LYSINE DECARBOXYLASE... 

ORNITHINE TRANSCARBAMOYLASE d-ORNITHINE 4,5-AMINOMUTASE ORNITHINE AMINOTRANSFERASE ORNITHINE DECARBOXYLASE Ornithine carbamoyltransferase,... 

KYNURENINE AMINOTRANSFERASE LEUCINE AMINOTRANSFERASE LYSINE 2,3-AMINOMUTASE LYSINE 6-AMINOTRANSFERASE LYSINE DECARBOXYLASE METHIONINE y-LYASE ORNITHINE AMINOTRANSFERASE PHENYLALANINE DECARBOXYLASE PHOSPHATIDYLSERINE DECARBOXYLASE... 

For this group of aminomutases PLP is required as a second coenzyme. Third, X is attached via a carbon atom the enzymes are called mutases. Methyl-malonyl-Co mutase is required for catabolism of propionate in the human body, and is one of only two known vitamin B12-... 

Aminomutases. The enzymes i -[5-Iysine mutase (which is also D-a-Iysine mutase) and D-omithine... 

Aminomutases (vitamin B12) 872, 874 8-Amino-7-oxo-nonanoate 718, 742 Aminopeptidase(s) 117, 609, 627 p-Aminopropionitrile 438 Aminopterin, inhibition of dehydrofolate reductase 805... 

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