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Information × Registration Number 0208U002817, 0107U010321 , R & D reports Title Investigation of influence of mutations in regulatory genes on lipomicin biosynthesis by culture Streptomyces aureofaciens Tu117 popup.stage_title Head Fedorenko V.O., Доктор біологічних наук Registration Date 19-02-2008 Organization Ivan Franko National University of Lviv. Journalism Department popup.description2 Object of the study - mechanisms of genetic regulation of lipomycin biosynthesis in the strain Streptomyces aureofeciens Tu117. The aim of the work is to investigate the function of the putative regulatory genes lipReg1, 2, 3, 4,5 in the biosynthesis of the antibiotic and to establish putative regatory mechanisms of this process. Methods: site-directed inactivation and expression of the genes (lipReg1, 2, 3, 4, 5), transfer of the constructed plasmids in to the strain S. aureofaciens Tu117 by means of conjugation with E. сoli, Southern DNA hybridization, polymerase chain reaction (PCR), reverse transcription (RT), High performance liquid chromatograthy. A gene cluster encoding type one polyketide synthase (PKSI) and nonribosomal peptide synthase (NRPS) was identified in the chromosome of Streptomyces aureofaciens T?117. This cluster was shown to be responsible for the production of the acyclic polyene antibiotic ?-lipomycin and consequently was named lip. Sequence analysis of the lip-cluster has revealed presence of five putative regulatory genes, lipReg1, lipReg2, lipReg3, lipReg4 and lipReg5. They are congregated into subcluster at the left end of the cluster. Such diversity of putative regulatory genes within single biosynthesis gene cluster can reflect the existence of complex regulatory machinery responsible for fine-tuning of lipomycin production. In this report we describe results of direct inactivation of putative regulatory genes within the lip-cluster, analysis of obtained mutants with respect to ?-lipomycin production and lip-genes expression, and results of complementation studies of regulatory mutants. All mentioned experiments lead to identification of interactions between studied regulatory factors and establishment of primary regulatory hierarchy. Based on our results, we could propose a preliminary model of lipomycin biosynthesis regulation. The lipReg4 gene product is directly controlling lipomycin biosynthesis structural genes expression and Product Description popup.authors popup.nrat_date 2020-04-02 Close