Project description:Streptomyces bingchenggensis is a soil bacterium that produces a family of macrolide antibiotics, milbemycins, which is commercially important in crop protection, human and veterinary medicine. After the complete genome sequence, and annotation, for further development of our gene expression approach to biosynthesis, we have employed whole genome microarray expression profiling as a discovery platform to obtain improved specificity and sensitivity of gene expression analysis, allowing a global and at the same time detailed picture of how gene clusters for secondary metabolism are modulated. In the result, we confirmed the expression mil and nan gene cluster, furthermore, pks3, pks5 and nrps7, nrps8 also showed significant gene expression, but no obvious products detected. In Streptomyces bingchenggensis, there are also corresponding genes belonging to Defense mechanisms, which is much more than other Streptomyces, for the resistance of own metabolites and dealing with complex environmental factors.
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.
Project description:This project aims to discover novel bioactive compounds from Streptomyces isolated from the rhizosphere from wild medicinal plants from Hamedan province, Iran. Proteomics is used to assist in discovery and characterization of the compounds. Streptomyces isolates are grown on ISP-4 medium for three days, proteins were extracted and analysed by shotgun proteomics.
Project description:Chitin is the second most abundant biopolymer present in soils and is utilized by antibiotic-producing Streptomyces species. Its monomer, N-acetylglucosamine (NAG), regulates the developmental program of the model organism Streptomyces coelicolor. NAG blocks differentiation when growing on rich medium whilst it promotes development on poor culture media. We report here the negative effect of NAG on tacrolimus (FK506) production in Streptomyces tsukubaensis NRRL 18488 growing on a defined rich medium. Using microarrays technology, we found that GlcNAc represses the transcription of fkbN, encoding the main transcriptional activator of the tacrolimus biosynthetic cluster, and of ppt1, encoding a phosphopantheteinyltransferase involved in tacrolimus biosynthesis. On the contrary, NAG stimulated transcription of genes related to amino acid and nucleotide biosynthesis, DNA replication, RNA translation, glycolysis, pyruvate metabolism, and key gene members of the PHO regulon. The results obtained support those previously reported for S. coelicolor, but some important differences were observed
Project description:The RNA sequencing approach was utilized to carry out a comparative transcriptome analysis between Streptomyces hygroscopicus 5008 wild-type and a genetically engineered strain. The A-factor-like cascade play an important role in the regulation of validamycin biosynthesis by Streptomyces hygroscopicus 5008, and the pleiotropic regulator AdpA-H may positively regulate the transcription of gene cluster for the biosynthesis. shbR1 and shbR3 as the A-factor receptor homolog genes, could repress the transcription of AdpA-H. By tandem deletions of these genes, the production and productivity of validamcyin was significantly enhanced. To explore the effects of the shbR1/R3 double deletion of the overall cellular metabolism, the RNA sequencing approach was utilized to carry out a comparative transcriptome analysis between wild-type and shbR1/shbR3 double mutant (genetically engineered strain).
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
