Identification of a gene encoding a thioredoxin-like product necessary for cytochrome c biosynthesis and symbiotic nitrogen fixation in Rhizobium leguminosarum.
AUTOR(ES)
Vargas, C
RESUMO
A Tn5-induced mutant of Rhizobium leguminosarum bv. viciae could not form nitrogen-fixing nodules on pea or vetch because of a lesion in electron transport to oxygen. The mutant lacked spectroscopically detectable cytochromes c and aa3. No proteins containing c-type cytochrome could be identified in the mutant by heme staining of proteins fractionated on polyacrylamide gels, indicating that the mutant was defective in maturation of all c-type cytochromes. The Tn5 mutation was determined to be located in a gene that was called cycY. The cycY gene product is homologous to the thioredoxin-like protein HelX involved in the assembly of c-type cytochromes in Rhodobacter capsulatus and to an open reading frame from a Bradyrhizobium japonicum gene cluster containing other genes involved in cytochrome c biogenesis. Our observations are consistent with CycY functioning as a thioredoxin that reduces cysteine residues in apocytochromes c before heme attachment.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=205611Documentos Relacionados
- Characterization of the cycHJKL genes involved in cytochrome c biogenesis and symbiotic nitrogen fixation in Rhizobium leguminosarum.
- Disruption of a gene encoding a novel thioredoxin-like protein alters the cyanobacterial photosynthetic apparatus.
- Generating an Unfoldase from Thioredoxin-like Domains
- Cytochromes c biogenesis in a photosynthetic bacterium requires a periplasmic thioredoxin-like protein.
- Identification of a rhizosphere protein encoded by the symbiotic plasmid of Rhizobium leguminosarum.