Thermodynamic characterization of the redox centers within dimethylsulfide dehydrogenase.
Dimethylsulfide (DMS) dehydrogenase is a complex heterotrimeric enzyme that catalyzes the oxidation of DMS to DMSO and allows Rhodovulum sulfidophilum to grow under photolithotrophic conditions with DMS as the electron donor. The enzyme is a 164 kDa heterotrimer composed of an alpha-subunit that binds a bis(molybdopterin guanine dinucleotide)Mo cofactor, a polyferredoxin beta-subunit, and a gamma-subunit that contains a b-type heme. In this study, we describe the thermodynamic characterization of the redox centers within DMS dehydrogenase using EPR- and UV-visible-monitored potentiometry. Our results are compared with those of other bacterial Mo enzymes such as NarGHI nitrate reductase, selenate reductase, and ethylbenzene dehydrogenase. A remarkable similarity in the redox potentials of all Fe-S clusters is apparent.
Creevey
Nicole L
NL
School of Molecular and Microbial Sciences and Centre for Metals in Biology, University of Queensland, Brisbane 4072, Australia.
McEwan
Alastair G
AG
Hanson
Graeme R
GR
Bernhardt
Paul V
PV
D001665:Binding Sites; D007506:Iron-Sulfur Proteins / Q000378:metabolism; D008982:Molybdenum / Q000737:chemistry; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry*; D041903:Rhodovulum / Q000201:enzymology; D013816:Thermodynamics
D007506:Iron-Sulfur Proteins; D008982:Molybdenum; D010088:Oxidoreductases; C100768:dimethylsulfide - acceptor oxidoreductase