Modulation of Lipid Metabolism and Spiramycin Biosynthesis in Streptomyces ambofaciens Unstable Mutants
AUTOR(ES)
Schauner, Catherine
FONTE
American Society for Microbiology
RESUMO
Streptomyces ambofaciens is prone to genetic instability involving genomic rearrangements at the extremities of the chromosomal DNA. An amplified DNA sequence (ADS205), including an open reading frame (orfPS), is responsible for the reversible loss of spiramycin production in the mutant strain NSA205 (ADS205+ Spi−). The product of orfPS is homologous to polyketide synthase systems (PKSs) involved in the biosynthesis of erythromycin and rapamycin and is overexpressed in strain NSA205 compared with the parental strain RP181110. As PKSs and fatty acid synthase systems have the same precursors, we tested the possibility that overexpression of orfPS also affects lipid metabolism in strain NSA205. This report focuses on comparative analysis of lipids in strain RP181110, the mutant strain NSA205, and a derivative, NSA228 (ADS205− Spi+). NSA205 showed a dramatically depressed lipid content consisting predominantly of phospholipids and triacylglycerols. This lipid content was globally restored in strain NSA228, which had lost ADS205. Furthermore, strains RP181110 and NSA205 presented similar phospholipid and triacylglycerol compositions. No abnormal fatty acids were detected in NSA205.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=91403Documentos Relacionados
- Cloning of spiramycin biosynthetic genes and their use in constructing Streptomyces ambofaciens mutants defective in spiramycin biosynthesis.
- Selection of Streptomyces ambofaciens mutants that produce large quantities of spiramycin and determination of optimal conditions for spiramycin production.
- Amino acid catabolism and antibiotic synthesis: valine is a source of precursors for macrolide biosynthesis in Streptomyces ambofaciens and Streptomyces fradiae.
- Efficient plasmid transformation of Streptomyces ambofaciens and Streptomyces fradiae protoplasts.
- Isolation and characterization of natural allene oxides: unstable intermediates in the metabolism of lipid hydroperoxides.
