Replacement of tyrosine 181 by phenylalanine in gentisate 1,2-dioxygenase I from Pseudomonas alcaligenes NCIMB 9867 enhances catalytic activities.

ABSTRACT: xlnE, encoding gentisate 1,2-dioxygenase (EC 1.13.11.4), from Pseudomonas alcaligenes (P25X) was mutagenized by site-directed mutagenesis. The mutant enzyme, Y181F, demonstrated 4-, 3-, 6-, and 16-fold increases in relative activity towards gentisate and 3-fluoro-, 4-methyl-, and 3-methylgentisate, respectively. The specific mutation conferred a 13-fold higher catalytic efficiency (k(cat)/Km) on Y181F towards 3-methylgentisate than that of the wild-type enzyme.

SUBMITTER: Tan CL 

PROVIDER: S-EPMC1272980 | biostudies-literature | 2005 Nov

REPOSITORIES: biostudies-literature