Isolation and characterization of a high molecular weight cytochrome from the sulfate reducing bacterium Desulfovibrio gigas

FEBS Letters

Chen, Liang¹  Teixeira, Miguel²  Le Gall, Jean¹  Xavier, António V.²  Pereira, Manuela M.² 

[1] Department of Biochemistry, The University of Georgia, Athens, GA 30602, USA;Instituto de Tecnologia Química e Biológica and Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Apt. 127, 2780 Oeiras, Portugal

关键词: Cytochrome c;    Multiheme cytochrome;    Desulfovibrio gigas;    N-Terminal sequence;    Electron transfer;    Electron paramagnetic resonance;    DEAE;    diethyl aminoethyl;    Hmc;    high molecular weight c-type cytochrome;    SDS-PAGE;    sodium dodecylsulfate-polyacrylamide gel electrophoresis;    Tris;    tris (hydroxymethyl) aminomethane;   

DOI  :  10.1016/0014-5793(94)00563-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A high molecular weight c-type cytochrome (Hmc) was purified and characterized from Desulfovibrio gigas. The molecular weight was estimated to be 67 kDa by SDS-PAGE and its N-terminus is homologous to those of the 16 hemes containing high molecular weight cytochrome c from Desulfovibrio vulgaris strains Hildenborough and Miyazaki. The purified hemoprotein shows c-type cytochrome absorption spectrum with ε₅₅₃(red) = 368 mM⁻¹ · cm⁻¹. A band at 640 nm, characteristic of high-spin hemes, was detected. The EPR spectra show the presence of two high-spin heme species, plus several non-equivalent low-spin hemes. The heme reduction potentials, at pH 7.6, range from −50 mV to −315 mV. In contrast to what has been described for D. vulgaris Hmc, the protein isolated from D. gigas directly accepts electrons from hydrogenase and further reduces other redox proteins.

【 授权许可】

Unknown