title: Functional expression of SCO7832 stimulates tautomycetin production via pathway-specific regulatory gene overexpression in Streptomyces sp. CK4412.
abstract: Comparative transcriptome analysis has revealed several acidic pH shock-induced genes presumably involved with stimulation of antibiotic production by S. coelicolor (Kim et al. Appl Microbiol Biotechnol 2007). Streptomyces sp. CK4412 produces a novel T cell-specific immunosuppressive compound, tautomycetin (TMC). When cultured at acidic pH medium, it also exhibited higher TMC productivity. To verify a gene responsible for acidic pH shock-induced TMC stimulation, a putative acid-shock-induced gene, SCO7832 encoding an Na(+)/H(+) antiporter protein, was cloned under the influence of a strong constitutive ermE* promoter in an integrative expression pSET152 vector. This was followed by its conjugation into the TMC-producing Streptomyces sp. CK4412. Comparing TMC production and antifungal activity of wild-type and the SCO7832-containing exconjugant revealed that SCO7832 stimulated TMC production more than 3.5-fold in Streptomyces sp. CK4412. The over-expression of SCO7832 did not affect the ratio between intra- and extra-cellular TMC productions. However, it significantly stimulated the expression of a TMC-specific positive regulatory gene. This implies that the stimulatory effect of SCO7832 functions in TMC-producing Streptomyces sp. CK4412 via up-regulation of a TMC pathway-specific positive regulatory gene, tmcN overexpression.
authors.affiliation: Department of Biological Engineering, Inha University, Incheon 402-751, Korea.
authors.forename: Shin-Hae
authors.initials: SH
authors.lastname: Park
authors.forename: Si-Sun
authors.initials: SS
authors.lastname: Choi
authors.forename: Yoon Jung
authors.initials: YJ
authors.lastname: Kim
authors.forename: Yong Keun
authors.initials: YK
authors.lastname: Chang
authors.forename: David H
authors.initials: DH
authors.lastname: Sherman
authors.forename: Eung-Soo
authors.initials: ES
authors.lastname: Kim
mesh_terms: D000143:Acids / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D053898:Biosynthetic Pathways / Q000235:genetics*; D005663:Furans; D015870:Gene Expression; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005818:Genetic Engineering; D008055:Lipids / Q000096:biosynthesis*; D011995:Recombination, Genetic; D048372:Streptomyces coelicolor / Q000235:genetics* / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D000143:Acids; D000900:Anti-Bacterial Agents; D005663:Furans; D008055:Lipids; C058744:tautomycetin