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 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 Aigle, B. Articles by Decaris, B. Search for Related Content PubMed PubMed Citation Articles by Aigle, B. Articles by Decaris, B. Agricola Articles by Aigle, B. Articles by Decaris, B.

An amplifiable and deletable locus of Streptomyces ambofaciens RP181110 contains a very large gene homologous to polyketide synthase genes

Dominique Schneider

Jean-Marc Simonet

Laboratoire de Génétique et Microbiologie, Associé INRA, Faculté des Sciences, Université Henri Poincaré, Nancy I, BP 239, 54506 Vandoeuvre-lès-Nancy, France

¹Author for correspondence: Bernard Decaris. Tel: +33 83 91 20 96. Fax: +33 83 91 25 00. e-mail: decaris@nancy.inra.fr

ABSTRACT

Streptomyces ambofaciens RP181110 produces the macrolide polyketide spiramycin. Like many other Streptomyces species, the RP181110 strain is prone to genetic instability involving genomic rearrangements (deletions and/or amplifications) in the large unstable region of the genome. It has previously been demonstrated that the amplification of a particular locus (AUD205) affects spiramycin biosynthesis and, conversely, the loss of this amplification is correlated with the restoration of antibiotic production. This report focuses on a 0.93 kb reiterated fragment specific for the AUD205 locus. Sequencing of 3596 bp including this reiteration revealed the presence of an ORF (orfPS) whose potential product was highly homologous to the EryA and Raps proteins, responsible for the biosynthesis of erythromycin in Saccharopolyspora erythraea and rapamycin in Streptomyces hygroscopicus, respectively. orfPS encodes a protein with at least four successive domains: ketoacyl synthase, acyltransferase, ketoreductase and acyl carrier protein. This organization is very similar to most eryA and rap modules. The reiterated sequence corresponds to the acyltransferase domain. orfPS was transcribed during rapid growth and stationary phase in RP181110 and overtranscribed in the amplified mutant. Both these results suggest that the gene encodes a type I polyketide synthase and its reorganization is responsible for the loss of spiramycin production in the amplified strains.

Present address: Université de Paris-Sud, CNRS-URA 1354, Bat. 400, 91405 Orsay Cedex, France.

Present address: John Innes Centre, Norwich Research Park, Colney Lane, Norwich NR4 7UH, UK.

This article has been cited by other articles:

				X. Pang, B. Aigle, J.-M. Girardet, S. Mangenot, J.-L. Pernodet, B. Decaris, and P. Leblond Functional Angucycline-Like Antibiotic Gene Cluster in the Terminal Inverted Repeats of the Streptomyces ambofaciens Linear Chromosome Antimicrob. Agents Chemother., February 1, 2004; 48(2): 575 - 588. [Abstract] [Full Text] [PDF]

				E. Schmid, C. Buchler, and J. Altenbuchner AUD4, a new amplifiable element from Streptomyces lividans Microbiology, December 1, 1999; 145(12): 3331 - 3341. [Abstract] [Full Text] [PDF]

				C. Schauner, A. Dary, A. Lebrihi, P. Leblond, B. Decaris, and P. Germain Modulation of Lipid Metabolism and Spiramycin Biosynthesis in Streptomyces ambofaciens Unstable Mutants Appl. Envir. Microbiol., June 1, 1999; 65(6): 2730 - 2737. [Abstract] [Full Text]

				G. Fischer, T. Wenner, B. Decaris, and P. Leblond Chromosomal arm replacement generates a high level of intraspecific polymorphism in the terminal inverted repeats of the linear chromosomal DNA of Streptomyces ambofaciens PNAS, November 24, 1998; 95(24): 14296 - 14301. [Abstract] [Full Text] [PDF]