||Novel Pathway of Toluene Catabolism in the Trichloroethylene-Degrading Bacterium G4.
Shields, M. S. ;
Montgomery, S. O. ;
Chapman, P. J. ;
Cuskey, S. M. ;
Pritchard, P. H. ;
||Technical Resources, Inc., Gulf Breeze, FL.;Environmental Research Lab., Gulf Breeze, FL.
Chemical reactions ;
Biological pathways ;
Enzyme activation ;
High performance liquid chromatography ;
Mixed function oxidases
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
o-Cresol and 3-methylcatechol were identified as successive transitory intermediates of toluene catabolism by the trichloroethylene-degrading bacterium G4. The absence of a toluene dihydrodiol intermediate or toluene dioxygenase and toluene dihydrodiol dehydrogenase activities suggested that G4 catabolizes toluene by a unique pathway. Formation of a hybrid species of 18O- and 16O-labeled 3-methylcatechol from toluene in an atmosphere of 180(2) and 160(2) established that G4 catabolizes toluene by successive monooxygenations at the ortho and meta positions. Detection of trace amounts of 4-methylcatechol from toluene catabolism suggested that the initial hydroxylation of toluene was not exclusively at the ortho position. Further catabolism of 3-methylcatechol was found to proceed via catechol-2,3-dioxygenase and hydroxymuconic semialdehyde hydrolase activities. (Copyright (c) 1989 American Society for Microbiology.)