Table 6.

Well-characterized Paracoccus c-type cytochromes

CytochromecMol mass (kDa)No. of c heme centersGeneRole or probable role
Cytochromec 550 141 cycA General periplasmic electron carrier
Cytochromec 1 45a 1 fbcC Component of bc1 complex
Cytochromec 552 221 cycM Electron donor toaa 3-type cytochrome oxidase
Cytochromec 551i 181 mxaG Electron acceptor for MDH
Cytochromec 553i 231 cycB Putative electron carrier during methylotrophic growth
Cytochromec 551 (putative)402 soxD Electron transport during growth on thiosulfate
Cytochromec121Unknown
Cytochrome cperoxidase422Removal of hydrogen peroxide from the periplasm
Cytochromecd 1 651 nirS Nitrite reductase
CcoO301 ccoO Component ofcbb 3-type cytochrome oxidase
CcoP452 ccoP Component ofcbb 3-type cytochrome oxidase
MauG402 mauG Synthesis of prosthetic group of MADH
NapB152 napB Component of periplasmic nitrate reductase
NapC274 napC NirT homologue, electron donor to periplasmic nitrate reductase
NirC101 nirC Unknown
NorC141 norC Component of nitric oxide reductase
SoxE261 soxE Electron transport during growth on thiosulfate
  • a Cytochrome c 1migrates with an apparent molecular mass of 60 to 68 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis.