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Characterization of the protocatechuic acid catabolic gene cluster from Streptomyces sp. strain 2065.

ABSTRACT: Protocatechuate 3,4-dioxygenase (EC 1.13.11.3) catalyzes the ring cleavage step in the catabolism of aromatic compounds through the protocatechuate branch of the beta-ketoadipate pathway. A protocatechuate 3,4-dioxygenase was purified from Streptomyces sp. strain 2065 grown in p-hydroxybenzoate, and the N-terminal sequences of the beta- and alpha-subunits were obtained. PCR amplification was used for the cloning of the corresponding genes, and DNA sequencing of the flanking regions showed that the pcaGH genes belonged to a 6. 5-kb protocatechuate catabolic gene cluster; at least seven genes in the order pcaIJFHGBL appear to be transcribed unidirectionally. Analysis of the cluster revealed the presence of a pcaL homologue which encodes a fused gamma-carboxymuconolactone decarboxylase/beta-ketoadipate enol-lactone hydrolase previously identified in the pca gene cluster from Rhodococcus opacus 1CP. The pcaIJ genes encoded proteins with a striking similarity to succinyl-coenzyme A (CoA):3-oxoacid CoA transferases of eukaryotes and contained an indel which is strikingly similar between high-G+C gram-positive bacteria and eukaryotes.

SUBMITTER: Iwagami SG

PROVIDER: S-EPMC92014 | biostudies-literature | 2000 Apr

REPOSITORIES: biostudies-literature

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Characterization of the protocatechuic acid catabolic gene cluster from Streptomyces sp. strain 2065.

Iwagami S G SG Yang K K Davies J J

Applied and environmental microbiology 20000401 4

Protocatechuate 3,4-dioxygenase (EC 1.13.11.3) catalyzes the ring cleavage step in the catabolism of aromatic compounds through the protocatechuate branch of the beta-ketoadipate pathway. A protocatechuate 3,4-dioxygenase was purified from Streptomyces sp. strain 2065 grown in p-hydroxybenzoate, and the N-terminal sequences of the beta- and alpha-subunits were obtained. PCR amplification was used for the cloning of the corresponding genes, and DNA sequencing of the flanking regions showed that t ...[more]

PMID: 10742233

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Dataset Information

Characterization of the protocatechuic acid catabolic gene cluster from Streptomyces sp. strain 2065.

Publications

Characterization of the protocatechuic acid catabolic gene cluster from Streptomyces sp. strain 2065.

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