Gene Knockout Of Saccharopolyspora Erythraea And Function Research On SACE₀069

Erythromycin, produced by fermentation of the Saccharopolyspora erythraea, and its derivatives are widely used. To improve erythromycin production and to reveal metabolic regulatory networks, more and more genetic engineering technology research and genetically alteration are focused on Saccharopolyspora erythraea.In this study, we optimized transformation system of the wide-type strain NRRL23338including electroporation, conjugation, PEG-mediated transformation of protoplasts, and achieved SACE₀069, SACE₀500, SACE₁897, SACE₃795four gene knock-out mutants successfully by PEG-mediated transformation of protoplasts. NsdA protein, as a negative regulation of gene found in Streptomyces coelicolor, is widely explored in some microorganisms. SACE₀069is a highly homologous gene in NRRL23338of nsdA. Bacteria phenotypic differences experiments show that SACE₀069gene plays a negative regulation at the Saccharopolyspora erythraea spores differentiation and erythromycin synthesis. In addition, transcription experimental data shows that there are more than500and120two and three fold changed expression genes. Among those genes, many of them were belonged to the energy metabolism, glucose metabolism, amino acid metabolism and so on. According to the experimental data of the transcriptome, we designed EMSA experiment and got two suspected target genes SACE₆415and SACE6240.To some extent, what we have done on SACE₀069gene function provides a new theoretical foundation and research target sites for improving erythromycin yeilds. This topic also provides insights into the regulation and evolution of the Saccharopolyspora erythraea morphological differentiation.