Initiation of anaerobic degradation of p-cresol by formation of 4-hydroxybenzylsuccinate in desulfobacterium cetonicum.
The anaerobic bacterium Desulfobacterium cetonicum oxidized p-cresol completely to CO(2) with sulfate as the electron acceptor. During growth, 4-hydroxybenzylsuccinate accumulated in the medium. This finding indicated that the methyl group of p-cresol is activated by addition to fumarate, analogous to anaerobic toluene, m-xylene, and m-cresol degradation. In cell extracts, the formation of 4-hydroxybenzylsuccinate from p-cresol and fumarate was detected at an initial rate of 0.57 nmol min(-1) (mg of protein)(-1). This activity was specific for extracts of p-cresol-grown cells. 4-Hydroxybenzylsuccinate was degraded further to 4-hydroxybenzoyl-coenzyme A (CoA), most likely via beta-oxidation. 4-Hydroxybenzoyl-CoA was reductively dehydroxylated to benzoyl-CoA. There was no evidence of degradation of p-cresol via methyl group oxidation by p-cresol-methylhydroxylase in this bacterium.
Müller
J A
JA
Fakultät für Biologie, Universität Konstanz, 78457 Konstanz, Germany. jmueller@stanford.edu
Galushko
A S
AS
Kappler
A
A
Schink
B
B
D000214:Acyl Coenzyme A / Q000378:metabolism; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D003408:Cresols / Q000378:metabolism*; D020564:Deltaproteobacteria / Q000378:metabolism*; D008954:Models, Biological; D010636:Phenols / Q000378:metabolism*; D013386:Succinates / Q000378:metabolism*; D016999:Sulfur-Reducing Bacteria / Q000378:metabolism*
C419219:4-hydroxybenzylsuccinate; D000214:Acyl Coenzyme A; D003408:Cresols; D010636:Phenols; D013386:Succinates; C032538:4-cresol; C058482:4-hydroxybenzoyl-coenzyme A; C037817:benzoyl-coenzyme A