HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Yeoman, K. H. Articles by Johnston, A. W. B. Search for Related Content PubMed PubMed Citation Articles by Yeoman, K. H. Articles by Johnston, A. W. B. Agricola Articles by Yeoman, K. H. Articles by Johnston, A. W. B.

High Affinity Iron Acquisition in Rhizobium Leguminosarum Requires the cycHJKL Operon and the feuPQ Gene Products, which belong to the Family of Two-Component Transcriptional Regulators

Kay H. Yeoman^1,

Maria-Jesus Delgado^2,

¹School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
²John Innes Centre, Colney Lane, Norwich NR4 7UH, UK

ABSTRACT

The cycHJKL operon of Rhizobium leguminosarum has previously been shown to be involved in the maturation of cytochrome c, possibly by its involvement in the covalent attachment of haem to the apoprotein. Mutations in the cycHJKL genes abolish symbiotic nitrogen fixation. Here, we show that cyc mutants are pleiotropically defective. They have lost a high affinity iron acquisition system due to their failure to make or to export siderophores. They also accumulate protoporphyrin IX, the immediate precursor of haem. A model to account for these phenotypes is presented. Immediately upstream of cycH is a gene, lipA, which is predicted to encode an outer-membrane lipoprotein. Further upstream of lipA, there are two other genes, whose products are similar in sequence to the widespread family of two-component transcriptional regulators. These two genes, feuP and feuQ, did not affect the transcription of lipA, or of the cycHJKL operon. However, a mutation in feuQ also led to the loss of the high affinity iron uptake system, although siderophores were still produced.

³Author for correspondence: Andrew W. B. Johnston. Tel: + 44 1603 592264. Fax: +44 1603 542250.

Present address: Estacion experimental del Zaidin, c/o Professor Albareda, Granada, Spain.

Present address: Institute of Food Research, Colney Lane, Norwich NR4 7UA, UK.

This article has been cited by other articles:

				H. Wu, F. Mao, V. Olman, and Y. Xu Hierarchical classification of functionally equivalent genes in prokaryotes Nucleic Acids Res., April 1, 2007; 35(7): 2125 - 2140. [Abstract] [Full Text] [PDF]

				S. N. Yurgel, J. Berrocal, C. Wilson, and M. L. Kahn Pleiotropic effects of mutations that alter the Sinorhizobium meliloti cytochrome c respiratory system Microbiology, February 1, 2007; 153(2): 399 - 410. [Abstract] [Full Text] [PDF]

				C. Sanders, C. Boulay, and F. Daldal Membrane-Spanning and Periplasmic Segments of CcmI Have Distinct Functions during Cytochrome c Biogenesis in Rhodobacter capsulatus J. Bacteriol., February 1, 2007; 189(3): 789 - 800. [Abstract] [Full Text] [PDF]

				C. Sanders, M. Deshmukh, D. Astor, R. G. Kranz, and F. Daldal Overproduction of CcmG and CcmFHRc Fully Suppresses the c-Type Cytochrome Biogenesis Defect of Rhodobacter capsulatus CcmI-Null Mutants J. Bacteriol., June 15, 2005; 187(12): 4245 - 4256. [Abstract] [Full Text] [PDF]

				S. Lee, M. Flores-Encarnacion, M. Contreras-Zentella, L. Garcia-Flores, J. E. Escamilla, and C. Kennedy Indole-3-Acetic Acid Biosynthesis Is Deficient in Gluconacetobacter diazotrophicus Strains with Mutations in Cytochrome c Biogenesis Genes J. Bacteriol., August 15, 2004; 186(16): 5384 - 5391. [Abstract] [Full Text] [PDF]

				C. Baysse, S. Matthijs, M. Schobert, G. Layer, D. Jahn, and P. Cornelis Co-ordination of iron acquisition, iron porphyrin chelation and iron-protoporphyrin export via the cytochrome c biogenesis protein CcmC in Pseudomonas fluorescens Microbiology, December 1, 2003; 149(12): 3543 - 3552. [Abstract] [Full Text] [PDF]

				M. Wexler, J. D. Todd, O. Kolade, D. Bellini, A. M. Hemmings, G. Sawers, and A. W. B. Johnston Fur is not the global regulator of iron uptake genes in Rhizobium leguminosarum Microbiology, May 1, 2003; 149(5): 1357 - 1365. [Abstract] [Full Text] [PDF]

				J. D. Todd, M. Wexler, G. Sawers, K. H. Yeoman, P. S. Poole, and A. W. B. Johnston RirA, an iron-responsive regulator in the symbiotic bacterium Rhizobium leguminosarum Microbiology, December 1, 2002; 148(12): 4059 - 4071. [Abstract] [Full Text] [PDF]

				V. K. Viswanathan, S. Kurtz, L. L. Pedersen, Y. Abu Kwaik, K. Krcmarik, S. Mody, and N. P. Cianciotto The Cytochrome c Maturation Locus of Legionella pneumophila Promotes Iron Assimilation and Intracellular Infection and Contains a Strain-Specific Insertion Sequence Element Infect. Immun., April 1, 2002; 70(4): 1842 - 1852. [Abstract] [Full Text] [PDF]

				K. H. Yeoman, F. Wisniewski-Dye, C. Timony, J. B. Stevens, N. G. deLuca, J. A. Downie, and A. W. B. Johnston Analysis of the Rhizobium leguminosarum siderophore-uptake gene fhuA: differential expression in free-living bacteria and nitrogen-fixing bacteroids and distribution of an fhuA pseudogene in different strains Microbiology, April 1, 2000; 146(4): 829 - 837. [Abstract] [Full Text]

				A. Marais, G. L. Mendz, S. L. Hazell, and F. Megraud Metabolism and Genetics of Helicobacter pylori: the Genome Era Microbiol. Mol. Biol. Rev., September 1, 1999; 63(3): 642 - 674. [Abstract] [Full Text] [PDF]

				J. P. M. de Vrind, G. J. Brouwers, P. L. A. M. Corstjens, J. den Dulk, and E. W. de Vrind-de Jong The Cytochrome c Maturation Operon Is Involved in Manganese Oxidation in Pseudomonas putida GB-1 Appl. Envir. Microbiol., October 1, 1998; 64(10): 3556 - 3562. [Abstract] [Full Text]