Wbr. Pollock et G. Voordouw, AEROBIC EXPRESSION OF THE CYF GENE ENCODING CYTOCHROME C-553 FROM DESULFOVIBRIO-VULGARIS HILDENBOROUGH IN ESCHERICHIA-COLI, Microbiology, 140, 1994, pp. 879-887
Monohaem cytochrome c-553 from Desulfovibrio vulgaris Hildenborough is
encoded by the cyf gene which could be expressed in Escherichia coli
to yield the periplasmic holoform of cytochrome c-553. Covalent haem a
ttachment was shown by labelling with 5-amino4-C-14laevulinic acid,
the immediate precursor for haem biosynthesis. Visible-absorption spec
troscopy demonstrated that the haem environment in the recombinant pro
tein did not differ from the native protein. Optimal expression was ob
tained under aerobic conditions. Furthermore, efficient insertion of h
aem into a cytochrome c-553-beta-lactamase fusion protein could be dem
onstrated. We suggest that the varying success in heterologous express
ion of c-type cytochromes in E. coli may arise as a result of differen
ces in the physical properties of the apoproteins.