alexa Streptomyces clavuligerus relA-null mutants overproduce clavulanic acid and cephamycin C: negative regulation of secondary metabolism by (p)ppGpp.
Bioinformatics & Systems Biology

Bioinformatics & Systems Biology

Journal of Proteomics & Bioinformatics

Author(s): GomezEscribano JP, Martn JF, Hesketh A, Bibb MJ, Liras P

Abstract Share this page

Abstract The (p)ppGpp synthetase gene, relA, of Streptomyces clavuligerus was cloned, sequenced and shown to be located in a genomic region that is highly conserved in other Streptomyces species. relA-disrupted and relA-deleted mutants of S. clavuligerus were constructed, and both were unable to form aerial mycelium or to sporulate, but regained these abilities when complemented with wild-type relA. Neither ppGpp nor pppGpp was detected in the S. clavuligerus relA-deletion mutant. In contrast to another study, clavulanic acid and cephamycin C production increased markedly in the mutants compared to the wild-type strain; clavulanic acid production increased three- to fourfold, while that of cephamycin C increased about 2.5-fold. Complementation of the relA-null mutants with wild-type relA decreased antibiotic yields to approximately wild-type levels. Consistent with these observations, transcription of genes involved in clavulanic acid (ceaS2) or cephamycin C (cefD) production increased dramatically in the relA-deleted mutant when compared to the wild-type strain. These results are entirely consistent with the growth-associated production of both cephamycin C and clavulanic acid, and demonstrate, apparently for the first time, negative regulation of secondary metabolite biosynthesis by (p)ppGpp in a Streptomyces species of industrial interest. This article was published in Microbiology and referenced in Journal of Proteomics & Bioinformatics

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

  • 9th International Conference on Bioinformatics
    October 23-24, 2017 Paris, France
  • 9th International Conference and Expo on Proteomics
    October 23-25, 2017 Paris, France

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version