title: 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.
authors.affiliation: Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: S G
authors.initials: SG
authors.lastname: Iwagami
authors.forename: K
authors.initials: K
authors.lastname: Yang
authors.forename: J
authors.initials: J
authors.lastname: Davies
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015139:Blotting, Southern; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D006801:Humans; D062385:Hydroxybenzoates / Q000378:metabolism*; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D011520:Protocatechuate-3,4-Dioxygenase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013302:Streptomyces / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D062385:Hydroxybenzoates; C009091:protocatechuic acid; D011520:Protocatechuate-3,4-Dioxygenase