Photosynthesis Research

, Volume 57, Issue 2, pp 117–128

Photoinduced electron transfer and cytochrome content in obligate aerobic phototrophic bacteria from genera Erythromicrobium, Sandaracinobacter, Erythromonas, Roseococcus and Erythrobacter

  • Vladimir Yurkov
  • Barbara Schoepp
  • André Verméglio
Article

DOI: 10.1023/A:1006097120530

Cite this article as:
Yurkov, V., Schoepp, B. & Verméglio, A. Photosynthesis Research (1998) 57: 117. doi:10.1023/A:1006097120530

Abstract

The photosynthetic apparatus and the electron carriers of seven species of five different genera of obligate aerobic phototrophic bacteria have been characterized by biochemical and biophysical techniques. A tetrahemic reaction center (RC) bound cytochrome (cyt) was found in Erythromonas (Em.) ursincola, Sandaracinobacter (S.) sibiricus and Roseococcus (R.) thiosulfatophilus, but not in Erythromicrobium (E.) ezovicum, Erythromicrobium ramosum, Erythromicrobium hydrolyticum and Erythrobacter (Eb.) litoralis. In none of the studied species, photochemical activity was observed under anaerobic conditions. Under aerobic conditions, the photoinduced cyclic electron transfer involves a soluble c-type cyt for the seven species. The cyt content of soluble and membrane fractions is highly dependent upon the species. The Erythromicrobium species (E. ezovicum, E. ramosum and E. hydrolyticum) contains a major soluble cyt while the other species possess several soluble cyts, up to four in the case of Eb. litoralis. These cyts have been characterized in terms of midpoint potential and apparent molecular mass. The presence of cyt bc1 complexes has been clearly detected in Eb. litoralis, E. hydrolyticum, E. ezovicum and E. ramosum. These last three species also contain a high midpoint potential (350 mV) membrane-bound cyt c of unknown function.

aerobic phototrophic bacteriacytochromeelectron transfer

Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Vladimir Yurkov
    • 1
  • Barbara Schoepp
    • 3
  • André Verméglio
    • 1
  1. 1.Laboratoire de Bioénergétique CellulaireCEA/Cadarache, DEVMSt. Paul lez Durance, CedexFrance
  2. 2.Department of Microbiology & Immunology, #The University of British ColumbiaVancouver, BCCanada
  3. 3.Laboratoire d'Ingénierie des Protéines, Centre de Génétique Moléculaire, CNRSGif-sur-Yvette CedexFrance