title: Heterologous expression of a putative K+/H+ antiporter of S. coelicolor A3(2) enhances K+, acidic-pH shock tolerances, and geldanamycin secretion.
abstract: Heterologous expression of a putative K+/H+ antiporter of Streptomyces coelicolor A3(2) (designated as sha4) in E. coli and Streptomyces hygroscopicus JCM4427 showed enhanced tolerance to K+ stress, acidic-pH shock, and/or geldanamycin production under K+ stress. In a series of K+ extrusion experiments with sha4-carrying E. coli deficient in the K+/H+ antiporter, a restoration of impaired K+ extrusion activity was observed. Based on this, it was concluded that sha4 was a true K+/H+ antiporter. In different sets of experiments, the sha4-carrying E. coli showed significantly improved tolerances to K+ stresses and acidic-pH shock, whereas sha4-carrying S. hygroscopicus showed an improvement in K+ stress tolerance only. The sha4-carrying S. hygroscopicus showed much higher geldanamycin productivity than the control under K+ stress condition. In another set of experiments with a production medium, the secretion of geldanamycin was also significantly enhanced by the expression of sha4.
authors: Bio Lab, Energy R&D Center, SK Innovation Global Technology, Daejeon 305-712, Korea.
authors: Jae Yang
authors: JY
authors: Song
authors: Young Bin
authors: YB
authors: Seo
authors: Soon-Kwang
authors: SK
authors: Hong
authors: Yong Keun
authors: YK
authors: Chang
mesh_terms: D000143:Acids / Q000633:toxicity*; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D016227:Benzoquinones / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D005816:Genetic Complementation Test; D047029:Lactams, Macrocyclic / Q000378:metabolism*; D011188:Potassium / Q000633:toxicity*; D027961:Potassium-Hydrogen Antiporters / Q000235:genetics / Q000378:metabolism*; D048372:Streptomyces coelicolor / Q000201:enzymology* / Q000235:genetics; D013312:Stress, Physiological
chemical_list: D000143:Acids; D000900:Anti-Bacterial Agents; D016227:Benzoquinones; D047029:Lactams, Macrocyclic; D027961:Potassium-Hydrogen Antiporters; D011188:Potassium; C001277:geldanamycin