Project description:To investigate the effect of bldA deletion on gene expression in Streptomyces iranensis with respect to secondary metabolite cluster genes
Project description:We identified genome-wide binding regions of NdgR in Streptomyces coelicolor using chromatin immunoprecipitation sequencing (ChIP-seq). We constructed 6×myc-tagged NdgR strain using homologous recombination with myc-tagging vector. Analysis of the sequencing data aligned to Streptomyces coelicolor genome database (NC_003888).
Project description:This study compared the genome of Streptomyces rimosus rimosus against that of Streptomyces coelicolor. It also compared 4 strains with changes in oxytetracycline production and derived from G7, the type strain, against G7. Keywords: Comparative genomic hybridization
Project description:Fungal infections pose a great threat to public health and the existing four classes of antifungals have limitations due to high toxicity, drug-drug interactions, and emerging drug-resistance. Streptomyces spp. represent an important source of antimicrobial substances, notably including the antifungal agent amphotericin B. The rapamycin-producer Streptomyces iranensis displayed strong antifungal activities against Aspergillus. Revisiting its genome revealed several intriguing biosynthetic gene clusters, including one unparalleled Type I polyketide synthase, which codes for uncharacterized metabolites. The identification of a novel macrolide spirolactone (1) was facilitated through CRISPR-based gene editing, HR-ESI-MS analysis, followed by fermentation and purification processes. Their structures and absolute configurations were confirmed by NMR, MS and X-ray crystallography. Spirolactone harbors an undescribed carbon skeleton with 13 chiral centers, featuring a rare beta-lactone moiety, a [6,6]-spiroketal ring, and an unprecedented 7-oxo-octylmalonyl-CoA extender unit. Spirolactone displayed profound antifungal effects against numerous fungal pathogens, e.g. the genus Talaromyces and several sections of Aspergillus including clinically relevant species such as Aspergillus niger and A. tubingensis (section Nigri), A. terreus (section Terrei) and the azol-resistant A. calidoustus (section Usti). Proteomics analysis revealed spirolactone potentially disrupted the integrity of fungal cell walls and induced the expression of stress-response proteins in A. niger. Spirolactone represents a new class of potential agents leading to combat fungal infections.
Project description:Investigation of whole genome gene expression level changes in Streptomyces avermitilis delta-aveI mutant, compared to the wild-type strain. The mutants analyzed in this study are further described in Chen L, Lu Y., Chen J, Zhang W, Shu D, Qin Z, Yang S, Jiang W. (2008) Characterization of a negative regulator AveI for avermectin biosynthesis in Streptomyces avermitilis NRRL8165. Appl Microbiol Biotechnol 80(2): 277-86.
