This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Lang, S. E.
Right arrow Articles by Daldal, F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lang, S. E.
Right arrow Articles by Daldal, F.

 Previous Article  |  Next Article 

J. Bacteriol., Sep 1996, 5279-5290, Vol 178, No. 17
Copyright © 1996, American Society for Microbiology

Rhodobacter capsulatus CycH: a bipartite gene product with pleiotropic effects on the biogenesis of structurally different c-type cytochromes

SE Lang, FE Jenney Jr and F Daldal
Department of Biology, Plant Science Institute, University of Pennsylvania, Philadelphia 19104-6018, USA.

While searching for components of the soluble electron carrier (cytochrome c2)-independent photosynthetic (Ps) growth pathway in Rhodobacter capsulatus, a Ps- mutant (FJM13) was isolated from a Ps+ cytochrome c2-strain. This mutant could be complemented to Ps+ growth by cycA encoding the soluble cytochrome c2 but was unable to produce several c-type cytochromes. Only cytochrome c1 of the cytochrome bc1 complex was present in FJM13 cells grown on enriched medium, while cells grown on minimal medium contained at various levels all c-type cytochromes, including the membrane-bound electron carrier cytochrome cy. Complementation of FJM13 by a chromosomal library lacking cycA yielded a DNA fragment which also complemented a previously described Ps- mutant, MT113, known to lack all c-type cytochromes. Deletion and DNA sequence analyses revealed an open reading frame homologous to cycH, involved in cytochrome c biogenesis. The cycH gene product (CycH) is predicted to be a bipartite protein with membrane-associated amino- terminal (CycH1) and periplasmic carboxyl-terminal (CycH2) subdomains. Mutations eliminating CyCH drastically decrease the production or all known c-type cytochromes. However, mutations truncating only its CycH2 subdomain always produce cytochrome c1 and affect the presence of other cytochromes to different degrees in a growth medium-dependent manner. Thus, the subdomain CycH1 is sufficient for the proper maturation of cytochrome c1 which is the only known c-type cytochrome anchored to the cytoplasmic membrane by its carboxyl terminus, while CycH2 is required for efficient biogenesis of other c-type cytochromes. These findings demonstrate that the two subdomains of CycH play different roles in the biogenesis of topologically distinct c-type cytochromes and reconcile the apparently conflicting data previously obtained for other species.


This article has been cited by other articles:

  • Kranz, R. G., Richard-Fogal, C., Taylor, J.-S., Frawley, E. R. (2009). Cytochrome c Biogenesis: Mechanisms for Covalent Modifications and Trafficking of Heme and for Heme-Iron Redox Control. Microbiol. Mol. Biol. Rev. 73: 510-528 [Abstract] [Full Text]  
  • Sanders, C., Turkarslan, S., Lee, D.-W., Onder, O., Kranz, R. G., Daldal, F. (2008). The Cytochrome c Maturation Components CcmF, CcmH, and CcmI Form a Membrane-integral Multisubunit Heme Ligation Complex. J. Biol. Chem. 283: 29715-29722 [Abstract] [Full Text]  
  • Sanders, C., Boulay, C., Daldal, F. (2007). Membrane-Spanning and Periplasmic Segments of CcmI Have Distinct Functions during Cytochrome c Biogenesis in Rhodobacter capsulatus. J. Bacteriol. 189: 789-800 [Abstract] [Full Text]  
  • Sanders, C., Deshmukh, M., Astor, D., Kranz, R. G., Daldal, F. (2005). Overproduction of CcmG and CcmFHRc Fully Suppresses the c-Type Cytochrome Biogenesis Defect of Rhodobacter capsulatus CcmI-Null Mutants. J. Bacteriol. 187: 4245-4256 [Abstract] [Full Text]  
  • Deshmukh, M., Turkarslan, S., Astor, D., Valkova-Valchanova, M., Daldal, F. (2003). The Dithiol:Disulfide Oxidoreductases DsbA and DsbB of Rhodobacter capsulatus Are Not Directly Involved in Cytochrome c Biogenesis, but Their Inactivation Restores the Cytochrome c Biogenesis Defect of CcdA-Null Mutants. J. Bacteriol. 185: 3361-3372 [Abstract] [Full Text]  
  • Rios-Velazquez, C., Coller, R., Donohue, T. J. (2003). Features of Rhodobacter sphaeroides CcmFH. J. Bacteriol. 185: 422-431 [Abstract] [Full Text]  
  • Keightley, J. A., Sanders, D., Todaro, T. R., Pastuszyn, A., Fee, J. A. (1998). Cloning and Expression in Escherichia coli of the Cytochrome c552 Gene from Thermus thermophilus HB8. EVIDENCE FOR GENETIC LINKAGE TO AN ATP-BINDING CASSETTE PROTEIN AND INITIAL CHARACTERIZATION OF THE cycA GENE PRODUCTS. J. Biol. Chem. 273: 12006-12016 [Abstract] [Full Text]  
  • Goldman, B. S., Beck, D. L., Monika, E. M., Kranz, R. G. (1998). Transmembrane heme delivery systems. Proc. Natl. Acad. Sci. USA 95: 5003-5008 [Abstract] [Full Text]  
  • Xie, Z., Culler, D., Dreyfuss, B. W., Kuras, R., Wollman, F.-A., Girard-Bascou, J., Merchant, S. (1998). Genetic Analysis of Chloroplast c -Type Cytochrome Assembly in Chlamydomonas reinhardtii: One Chloroplast Locus and at Least Four Nuclear Loci Are Required for Heme Attachment. Genetics 148: 681-692 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»