Abstract
Cytochrome c'' from Methylophilus methylotrophus is an unusual monohaem protein that undergoes a major redox-linked spin-state transition: one of the two axial histidines bound to the iron in the oxidised form is detached upon reduction and a proton is taken up. A 3.5-kb DNA fragment, containing the gene encoding cytochrome c'' (cycA), has been cloned and sequenced. The cytochrome c'' gene codes for a pre-protein with a typical prokaryotic 20-residue signal sequence, suggesting that the protein is synthesised as a precursor which is processed during its secretion into the periplasm. The C-terminus of cytochrome c'' has homology with the corresponding region of an oxygen-binding haem protein (SHP) from phototrophically grown Rhodobacter sphaeroides. SHP is similar in size and in the location of its haem-binding site. Immediately downstream from cytochrome c'' a second open reading frame (ORF) codes for a 23-kDa protein with similarity to the cytochrome b-type subunit of Ni-Fe hydrogenase. The possibility of coordinated expression of cycA and this ORF is discussed. Copyright (C) 1999 Elsevier Science B.V.
Original language | English |
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Pages (from-to) | 55-61 |
Number of pages | 7 |
Journal | Biochimica et Biophysica Acta - Bioenergetics |
Volume | 1413 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Sep 1999 |
Keywords
- Cytochrome c''
- Methylophilus methylotrophus
- Nucleotide sequencing
- Redox protein