Open AccessTranscriptomic analysis of S treptomyces clavuligerus Δ ccaR :: tsr : effects of the cephamycin C ‐clavulanic acid cluster regulator CcaR on global regulation
Author(s) -
ÁlvarezÁlvarez R.,
RodríguezGarcía A.,
Santamarta I.,
PérezRedondo R.,
PrietoDomínguez A.,
MartínezBurgo Y.,
Liras P.
Publication year - 2014
Publication title -
microbial biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.287
H-Index - 74
ISSN - 1751-7915
DOI - 10.1111/1751-7915.12109
Subject(s) - streptomyces clavuligerus , biochemistry , gene cluster , biology , gene , mutant , transcriptome , clavulanic acid , gene expression , amoxicillin , antibiotics
Summary S treptomyces clavuligerus ATCC 27064 and S . clavuligerus Δ ccaR :: tsr cultures were grown in asparagine‐starch medium, and samples were taken in the exponential and stationary growth phases. Transcriptomic analysis showed that the expression of 186 genes was altered in the ccaR ‐deleted mutant. These genes belong to the cephamycin C gene cluster, clavulanic acid gene cluster, clavams, holomycin, differentiation, carbon, nitrogen, amino acids or phosphate metabolism and energy production. All the clavulanic acid biosynthesis genes showed M c values in the order of −4.23. The blip gene‐encoding a β‐lactamase inhibitory protein was also controlled by the cephamycin C ‐clavulanic acid cluster regulator ( M c −2.54). The expression of the cephamycin C biosynthesis genes was greatly reduced in the mutant ( M c values up to −7.1), while the genes involved in putative β‐lactam resistance were less affected ( M c average −0.88). Genes for holomycin biosynthesis were upregulated. In addition, the lack of clavulanic acid and cephamycin production negatively affected the expression of genes for the clavulanic acid precursor arginine and of miscellaneous genes involved in nitrogen metabolism ( amtB , glnB , glnA3 , glnA2 , glnA1 ). The transcriptomic results were validated by quantative reverse transcription polymerase chain reaction and luciferase assay of luxAB ‐coupled promoters. Transcriptomic analysis of the homologous genes of S . coelicolor validated the results obtained for S . clavuligerus primary metabolism genes.