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Evolution of arginine biosynthesis in the bacterial domain: novel gene-enzyme relationships from psychrophilic Moritella strains (Vibrionaceae) and evolutionary significance of N-alpha-acetyl ornithinase.

ABSTRACT: In the arginine biosynthetic pathway of the vast majority of prokaryotes, the formation of ornithine is catalyzed by an enzyme transferring the acetyl group of N-alpha-acetylornithine to glutamate (ornithine acetyltransferase [OATase]) (argJ encoded). Only two exceptions had been reported-the Enterobacteriaceae and Myxococcus xanthus (members of the gamma and delta groups of the class Proteobacteria, respectively)-in which ornithine is produced from N-alpha-acetylornithine by a deacylase, acetylornithinase (AOase) (argE encoded). We have investigated the gene-enzyme relationship in the arginine regulons of two psychrophilic Moritella strains belonging to the Vibrionaceae, a family phylogenetically related to the Enterobacteriaceae. Most of the arg genes were found to be clustered in one continuous sequence divergently transcribed in two wings, argE and argCBFGH(A) ["H(A)" indicates that the argininosuccinase gene consists of a part homologous to known argH sequences and of a 3' extension able to complement an Escherichia coli mutant deficient in the argA gene, encoding N-alpha-acetylglutamate synthetase, the first enzyme committed to the pathway]. Phylogenetic evidence suggests that this new clustering pattern arose in an ancestor common to Vibrionaceae and Enterobacteriaceae, where OATase was lost and replaced by a deacylase. The AOase and ornithine carbamoyltransferase of these psychrophilic strains both display distinctly cold-adapted activity profiles, providing the first cold-active examples of such enzymes.

SUBMITTER: Xu Y

PROVIDER: S-EPMC94458 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature

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Evolution of arginine biosynthesis in the bacterial domain: novel gene-enzyme relationships from psychrophilic Moritella strains (Vibrionaceae) and evolutionary significance of N-alpha-acetyl ornithinase.

Xu Y Y Liang Z Z Legrain C C Rüger H J HJ Glansdorff N N

Journal of bacteriology 20000301 6

In the arginine biosynthetic pathway of the vast majority of prokaryotes, the formation of ornithine is catalyzed by an enzyme transferring the acetyl group of N-alpha-acetylornithine to glutamate (ornithine acetyltransferase [OATase]) (argJ encoded). Only two exceptions had been reported-the Enterobacteriaceae and Myxococcus xanthus (members of the gamma and delta groups of the class Proteobacteria, respectively)-in which ornithine is produced from N-alpha-acetylornithine by a deacylase, acetyl ...[more]

PMID: 10692366

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Dataset Information

Evolution of arginine biosynthesis in the bacterial domain: novel gene-enzyme relationships from psychrophilic Moritella strains (Vibrionaceae) and evolutionary significance of N-alpha-acetyl ornithinase.

Publications

Evolution of arginine biosynthesis in the bacterial domain: novel gene-enzyme relationships from psychrophilic Moritella strains (Vibrionaceae) and evolutionary significance of N-alpha-acetyl ornithinase.

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