| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
2 CNRS, Institut de Génétique et Microbiologie, UMR 8621, Université Paris-Sud 11, 91405 Orsay Cedex, France
3 Laboratoire de Génétique et Microbiologie, UMR INRA 1128 IFR 110, Faculté des Sciences et Techniques, Université Henri Poincaré Nancy 1, Boulevard des Aiguillettes, BP239, 54506 Vandoeuvre-les-Nancy Cedex, France
Correspondence
Gregory L. Challis
G.L.Challis{at}warwick.ac.uk
Siderophore-mediated iron acquisition has been well studied in many bacterial pathogens because it contributes to virulence. In contrast, siderophore-mediated iron acquisition by saprophytic bacteria has received relatively little attention. The independent identification of the des and cch gene clusters that direct production of the tris-hydroxamate ferric iron-chelators desferrioxamine E and coelichelin, respectively, which could potentially act as siderophores in the saprophyte Streptomyces coelicolor A3(2), has recently been reported. Here it is shown that the des cluster also directs production of desferrioxamine B in S. coelicolor and that very similar des and cch clusters direct production of desferrioxamines E and B, and coelichelin, respectively, in Streptomyces ambofaciens ATCC 23877. Sequence analyses of the des and cch clusters suggest that components of ferric-siderophore uptake systems are also encoded within each cluster. The construction and analysis of a series of mutants of S. coelicolor lacking just biosynthetic genes or both the biosynthetic and siderophore uptake genes from the des and cch clusters demonstrated that coelichelin and desferrioxamines E and B all function as siderophores in this organism and that at least one of these metabolites is required for growth under defined conditions even in the presence of significant quantities of ferric iron. These experiments also demonstrated that a third siderophore uptake system must be present in S. coelicolor, in addition to the two encoded within the cch and des clusters, which show selectivity for coelichelin and desferrioxamine E, respectively. The ability of the S. coelicolor mutants to utilize a range of exogenous xenosiderophores for iron acquisition was also examined, showing that the third siderophore-iron transport system has broad specificity for tris-hydroxamate-containing siderophores. Together, these results define a complex system of multiple biosynthetic and uptake pathways for siderophore-mediated iron acquisition in S. coelicolor and S. ambofaciens.
Present address: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca, CP 62250, México.
Present address: CNRS, Institut de Génétique et Microbiologie, UMR 8621, Université Paris-Sud 11, 91405 Orsay Cedex, France.
This article has been cited by other articles:
|
|
 |
|
  G. L. Challis Mining microbial genomes for new natural products and biosynthetic pathways Microbiology, June 1, 2008; 154(6): 1555 - 1569. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Bunet, M. V. Mendes, N. Rouhier, X. Pang, L. Hotel, P. Leblond, and B. Aigle Regulation of the Synthesis of the Angucyclinone Antibiotic Alpomycin in Streptomyces ambofaciens by the Autoregulator Receptor AlpZ and Its Specific Ligand J. Bacteriol., May 1, 2008; 190(9): 3293 - 3305. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Lautru, D. Oves-Costales, J.-L. Pernodet, and G. L. Challis MbtH-like protein-mediated cross-talk between non-ribosomal peptide antibiotic and siderophore biosynthetic pathways in Streptomyces coelicolor M145 Microbiology, May 1, 2007; 153(5): 1405 - 1412. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
| J MED MICROBIOL | ALL SGM JOURNALS | |
