Diaz_1995_J.Biol.Chem_270_6403

Reference

Title : Identification of functional residues in a 2-hydroxymuconic semialdehyde hydrolase. A new member of the alpha\/beta hydrolase-fold family of enzymes which cleaves carbon-carbon bonds - Diaz_1995_J.Biol.Chem_270_6403
Author(s) : Diaz E , Timmis KN
Ref : Journal of Biological Chemistry , 270 :6403 , 1995
Abstract :

The 2-hydroxymuconic semialdehyde hydrolase, XylF, of the Pseudomonas putida TOL plasmid-encoded pathway for the catabolism of toluene and xylenes, catalyzes one of the rarest types of enzyme reaction (EC 3.7.1.9), the hydrolysis of a carbon-carbon bond in its substrate, the ring-fission product of 3-alkyl-substituted catechols. In this study, amino acid sequence comparisons between XylF and other hydrolases, and analysis of the similarity between the predicted secondary structure of XylF and the known secondary structure of the haloalkane dehalogenase from Xanthobacter autotrophicus strain GJ10, led us to identify several conserved residues likely to have a functional role in the catalytic center of XylF. Three amino acids, Ser107, Asp228, and His256, were found to be arranged in a sequential order similar to that in alpha/beta hydrolase-fold enzymes. Investigations of the potential functional role of these and other residues through amino acid modification and in vitro site-directed mutagenesis experiments provided evidence in support of the hypothesis that XylF is a serine hydrolase of the alpha/beta hydrolase-fold family of enzymes, and pointed to the residues identified above as the catalytic triad of XylF. These studies also provided information on other conserved residues in XylF-related enzymes. Interestingly, the substitution of Phe by Met in position 108 of XylF created an enzyme with increased thermostability and altered substrate specificity.

PubMedSearch : Diaz_1995_J.Biol.Chem_270_6403
PubMedID: 7890778
Gene_locus related to this paper: psepu-XYLF

Related information

Substrate HMSA
Gene_locus psepu-XYLF

Citations formats

Diaz E, Timmis KN (1995)
Identification of functional residues in a 2-hydroxymuconic semialdehyde hydrolase. A new member of the alpha\/beta hydrolase-fold family of enzymes which cleaves carbon-carbon bonds
Journal of Biological Chemistry 270 :6403

Diaz E, Timmis KN (1995)
Journal of Biological Chemistry 270 :6403