Purification and characterisation of periplasmic C-type cytochromes fromDesulfovibrio desulfuricans(NCIMB 8372)

摘要

Periplasmic extract fromDesulfovibrio desulfuricans(NCIMB 8372) was found to contain two different c-type cytochromes. One is tetraheme cytochrome c3and the other is monoheme cytochrome c553. Cytochrome c3could be purified by a procedure involving only one chromatographic step, whereas cytochrome c553required several such steps. Cytochrome c3was found to have a relative molecular mass of 14300 and an isoionic point higher than 9. Analysis of the redox potentials indicated one heme at -260 mV and three hemes around -330 mV. Cytochrome c553had a relative molecular mass of 7200, an isoionic point higher than 9 and a redox potential of 0 mV.