Keywords
How to Cite
Abstract
Background: Streptomyces clavuligerus was the producer of clavulanic acid, claR, a pathway-specific transcriptional regulator in S. clavuligerus, positively regulates clavulanic acid biosynthesis. In this study, the promoter-less kanamycin resistance gene neo was fused with claR to obtain strain NEO from S. clavuligerus F613-1. The claR-neo fusion strain NEO was mutated using physical and chemical mutagens and then screened under high concentrations of kanamycin for high-yield producers of clavulanic acid.
Results: The reporter gene neo was fused downstream of claR and used as an indicator for expression levels of claR in strain NEO. After three rounds of continuous treatment and screening, the high-yield clavulanic acid-producing strain M3-19 was obtained. In the shaking flask model, the clavulanic acid titer of M3-19 reached 4.33 g/L, which is an increase of 33% over the titer of 3.26 g/L for the starting strains S. clavuligerus F613-1 and NEO.
Conclusions: Our results indicate that neo can be effectively used as a reporter for the expression of late-stage biosynthetic genes when screening for high-yield strains and that this approach has strong potential for improving Streptomyces strains of industrial value.
Upon acceptance of an article by the journal, authors will be asked to transfer the copyright to Electronic Journal of Biotechnology, which is committed to maintain the electronic access to the journal and to administer a policy of fair control and ensure the widest possible dissemination of the information. The author can use the article for academic purposes, stating clearly the following: "Published in Electronic Journal of Biotechnology at DOI:10.2225/volXX-issueX-fulltext-XX".
The Copyright Transfer Agreement must be submitted as a signed scanned copy to biotec@ucv.cl. All authors must send a copy of this document.