Substitution, insertion, deletion, suppression, and altered substrate specificity in functional protocatechuate 3,4-dioxygenases.

ABSTRACT: Protocatechuate 3,4-dioxygenase is a member of a family of bacterial enzymes that cleave the aromatic rings of their substrates between two adjacent hydroxyl groups, a key reaction in microbial metabolism of varied environmental chemicals. In an appropriate genetic background, it is possible to select for Acinetobacter strains containing spontaneous mutations blocking expression of pcaH or -G, genes encoding the alpha and beta subunits of protocatechuate 3, 4-dioxygenase. The crystal structure of the Acinetobacter oxygenase has been determined, and this knowledge affords us the opportunity to understand how mutations alter function in the enzyme. An earlier investigation had shown that a large fraction of spontaneous mutations inactivating Acinetobacter protocatechuate oxygenase are either

SUBMITTER: D'Argenio DA 

PROVIDER: S-EPMC103785 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature