Roles of the enantioselective glutathione S-transferases in cleavage of beta-aryl ether.

ABSTRACT: Cleavage of the beta-aryl ether linkage is the most important process in lignin degradation. Here we characterize the three tandemly located glutathione S-transferase (GST) genes, ligF, ligE, and ligG, from low-molecular-weight lignin-degrading Sphingomonas paucimobilis SYK-6, and we describe the actual roles of these genes in the beta-aryl ether cleavage. Based on the identification of the reaction product by electrospray ionization-mass spectrometry, a model compound of beta-aryl ether, alpha-(2-methoxyphenoxy)-beta-hydroxypropiovanillone (MPHPV), was transformed by LigF or LigE to guaiacol and alpha-glutathionyl-beta-hydroxypropiovanillone (GS-HPV). This result suggested that LigF and LigE catalyze the nucleophilic attack of glutathione on the carbon atom at the beta position of MPHPV.

SUBMITTER: Masai E 

PROVIDER: S-EPMC150126 | biostudies-literature | 2003 Mar

REPOSITORIES: biostudies-literature