Journal article
Genetic evidence that the degradation of para-cresol by Geobacter metallireducens is catalyzed by the periplasmic para-cresol methylhydroxylase
Sungkyunkwan University1
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark2
Research Groups, Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark3
Bioelectrochemical Systems, Research Groups, Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark4
University of Massachusetts5
Two pathways for para-cresol (p-cresol) degradation by anaerobic bacteria have been elucidated; one involves fumarate addition at the methyl group of p-cresol by a hydroxylbenzylsuccinate synthase protein while the other utilizes a methylhydroxylase protein (PCMH) to catalyze hydroxylation of the methyl group of p-cresol.
In Geobacter metallireducens, in vitro enzymatic assays showed that p-cresol is degraded via the methylhydroxylation pathway. However, prior to this study these results had not been confirmed by genetic analyses. In this work, the gene coding for benzylsuccinate-CoA dehydrogenase (bbsG), an enzyme required for toluene degradation by G. metallireducens that is homologous to the p-hydroxybenzylsuccinyl-CoA dehydrogenase involved in p-cresol degradation by Desulfobacula toluolica Tol2 via fumarate addition, and the gene encoding the alpha prime subunit of PCMH (pcmI), were deleted to investigate the possibility of co-existing p-cresol degradation pathways in G. metallireducens.
The absence of a functional PcmI protein completely inhibited p-cresol degradation, while deletion of the bbsG gene had little impact. These results further support the observation that G. metallireducens utilizes a PCMH-initiated pathway for p-cresol degradation.
Language: | English |
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Year: | 2015 |
Pages: | fnv145 |
ISSN: | 15746968 and 03781097 |
Types: | Journal article |
DOI: | 10.1093/femsle/fnv145 |
ORCIDs: | Zhang, Tian |