CHARACTERIZATION AND EXPRESSION OF THE CO-TRANSCRIBED CYC1 AND CYC2 GENES ENCODING THE CYTOCHROME C(4) (C(552)) AND A HIGH-MOLECULAR-MASS CYTOCHROME-C FROM THIOBACILLUS-FERROOXIDANS ATCC33020
C. Appiaayme et al., CHARACTERIZATION AND EXPRESSION OF THE CO-TRANSCRIBED CYC1 AND CYC2 GENES ENCODING THE CYTOCHROME C(4) (C(552)) AND A HIGH-MOLECULAR-MASS CYTOCHROME-C FROM THIOBACILLUS-FERROOXIDANS ATCC33020, FEMS microbiology letters, 167(2), 1998, pp. 171-177
The sequence of the cyc1 gene encoding the Thiobacillus ferrooxidans A
TCC 33020 c(552) cytochrome, shows that this cytochrome is a 21-kDa pe
riplasmic ce-type cytochrome containing two similar monohaem domains.
The kinetics of reduction and the fact that cytochromes C-4 are consid
ered to be physiological electron donors of cytochrome oxidases sugges
t that the last steps of the iron respiratory chain are: rusticyanin -
-> cytochrome c(4) --> cytochrome oxidase. In Thiobacillus ferrooxidan
s, cyc1 is co-transcribed with the cyc2 gene, encoding a high-molecula
r-mass monohaem cytochrome c. This suggests that the cytochromes encod
ed by these genes belong to the same electron transfer chain. (C) 1998
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