Synthesis of 7-Oxo-8-Aminopelargonic Acid, a Biotin Vitamer, in Cell-free Extracts of Escherichia coli Biotin Auxotrophs1
AUTOR(ES)
Eisenberg, M. A.
RESUMO
The enzymatic synthesis of 7-oxo-8-aminopelargonic acid (7-KAP) from pimelyl-coenzyme A and l-alanine was demonstrated in cell-free extracts of a biotin mutant of Escherichia coli K-12 which excretes only 7-KAP into the growth medium. This biotin vitamer was identified by its chromatographic and electrophoretic properties. The enzyme (7-KAP synthetase) was repressed when the organism was grown in biotin concentrations greater than 0.2 ng/ml. The parent strain and members of other mutant groups that excrete 7-KAP, in addition to other vitamers, also exhibited synthetase activity. A mutant group that failed to excrete 7-KAP was further sub-divided into three groups, one of which lacked synthetase activity. These results are discussed in relation to a previously proposed scheme for biotin biosynthesis in which the formation of 7-KAP is considered the point of entry for pimelic acid into the biotin pathway.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=252447Documentos Relacionados
- Biosynthesis of Biotin: Synthesis of 7,8-Diaminopelargonic Acid in Cell-Free Extracts of Escherichia coli
- Biosynthesis of Desthiobiotin in Cell-free Extracts of Escherichia coli1
- Biosynthesis of 7,8-Diaminopelargonic Acid, a Biotin Intermediate, from 7-Keto-8-Aminopelargonic Acid and S-Adenosyl-l-Methionine1
- MACROMOLECULAR SYNTHESIS IN CELL-FREE PREPARATIONS FROM ESCHERICHIA COLI1
- Activation of Fatty Acid Synthesis in Cell-free Extracts of Saccharomyces cerevisiae