+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Disparate pathways for the biogenesis of cytochrome oxidases in Bradyrhizobium japonicum



Disparate pathways for the biogenesis of cytochrome oxidases in Bradyrhizobium japonicum



Journal of Biological Chemistry 285(21): 15704-15713



This work addresses the biogenesis of heme-copper terminal oxidases in Bradyrhizobium japonicum, the nitrogen-fixing root nodule symbiont of soybean. B. japonicum has four quinol oxidases and four cytochrome oxidases. The latter include the aa(3)- and cbb(3)-type oxidases. Although both have a Cu(B) center in subunit I, the subunit II proteins differ in having either a Cu(A) center (in aa(3)) or a covalently bound heme c (in cbb(3)). Two biogenesis factors were genetically studied here, the periplasmically exposed CoxG and ScoI proteins, which are the respective homologs of the mitochondrial copper-trafficking chaperones Cox11 and Sco1 for the formation of the Cu(B) center in subunit I and the Cu(A) center in subunit II of cytochrome aa(3). We could demonstrate copper binding to ScoI in vitro, a process for which the thiols of cysteine residues 74 and 78 in the ScoI polypeptide were shown to be essential. Knock-out mutations in the B. japonicum coxG and scoI genes led to loss of cytochrome aa(3) assembly and activity in the cytoplasmic membrane, whereas the cbb(3)-type cytochrome oxidase apparently remained unaffected. This suggests that subunit I of the cbb(3)-type oxidase obtains its copper cofactor via a different pathway than cytochrome aa(3). In contrast to the coxG mutation, the scoI mutation caused a decreased symbiotic nitrogen fixation activity. We hypothesize that a periplasmic B. japonicum protein other than any of the identified Cu(A) proteins depends on ScoI and is required for an effective symbiosis.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 052653263

Download citation: RISBibTeXText

PMID: 20335176

DOI: 10.1074/jbc.m109.085217


Related references

Copper starvation-inducible protein for cytochrome oxidase biogenesis in Bradyrhizobium japonicum. Journal of Biological Chemistry 287(46): 38812-38823, 2012

Molecular analysis of terminal oxidases in electron transport pathways of Bradyrhizobium japonicum and Azotobacter vinelandii. Nitrogen fixation: achievements and objectives Proceedings, 8th international congress on nitrogen fixation, Knoxville, USA, May 20-26, 1990: 301-308, 1990

Bradyrhizobium japonicum TlpA, a novel membrane-anchored thioredoxin-like protein involved in the biogenesis of cytochrome aa3 and development of symbiosis. Embo Journal 12(9): 3373-3383, 1993

Disparate oxygen responsiveness of two regulatory cascades that control expression of symbiotic genes in Bradyrhizobium japonicum. Journal of Bacteriology 185(18): 5639-5642, 2003

From one gene to two proteins: the biogenesis of cytochromes b and c1 in Bradyrhizobium japonicum. Proceedings of the National Academy of Sciences of the United States of America 88(11): 5001-5005, 1991

Disparate oxygen responsiveness of two regulatory cascades controlling the expression of nitrogen fixation genes in Bradyrhizobium japonicum. Finan, Turlough M , Reprint Author, O'Brian, Mark R, Layzell, David B, Vessey, J Kevin, Newton, William Nitrogen fixation: Global perspectives: 403, 2002

The unusual behaviour of the putative terminal oxidases of Bradyrhizobium japonicum bacteroids revealed by low-temperature photodissociation studies. Biochimica et biophysica acta: International journal of biochemistry and biophysics1990 1019(3): 225-232, 1990

Efficiency of different formulations of Bradyrhizobium japonicum and effect of co-inoculation of Bacillus subtilis with two different strains of Bradyrhizobium japonicum. World Journal of Microbiology and Biotechnology 28(7): 2541-2550, 2012

Regulation of cytochrome aa 3 in bradyrhizobium japonicum. Abstracts of the General Meeting of the American Society for Microbiology 92: 208, 1992

The cycHJKL gene cluster plays an essential role in the biogenesis of c-type cytochromes in Bradyrhizobium japonicum. Molecular and general genetics: MGG 247(1): 27-38, 1995

Isolation of a cytochrome aa(3) gene from Bradyrhizobium japonicum. Proceedings of the National Academy of Sciences of the United States of America 84(10): 3219-3223, 1987

A cytochrome P450 operon from Bradyrhizobium japonicum. Abstracts of the General Meeting of the American Society for Microbiology 94: 335, 1994

Bradyrhizobium canariense sp. nov., an acid-tolerant endosymbiont that nodulates endemic genistoid legumes (Papilionoideae: Genisteae) from the Canary Islands, along with Bradyrhizobium japonicum bv. genistearum, Bradyrhizobium genospecies alpha and Bradyrhizobium genospecies beta. International Journal of Systematic and Evolutionary Microbiology 55(2): 569-575, 2005

Bradyrhizobium canariense sp. nov., an acid-tolerant endosymbiont that nodulates endemic genistoid legumes (Papilionoideae: Genisteae) from the Canary Islands, along with Bradyrhizobium japonicum bv. genistearum, Bradyrhizobium genospecies alpha and Bradyrhizobium genospecies beta. International Journal of Systematic and Evolutionary Microbiology 55(Pt 2): 569-575, 2005

Presence of natural variants of Bradyrhizobium elkanii and Bradyrhizobium japonicum and detection of Bradyrhizobium yuanmingense in Phitsanulok province, Thailand. Scienceasia 38(1): 24-29, 2012