title: Sporulation of several species of Streptomyces in submerged cultures after nutritional downshift.
abstract: Streptomyces griseus ATCC 10137, S. griseus IMRU 3570, S. griseus JI 2212, S. acrimycini JI 2236 and S. albus G sporulated abundantly in several liquid media after nutritional downshift. Spores formed in submerged cultures were viable and as thermoresistant as aerial spores. Scanning electron microscopy showed that submerged spores are morphologically similar to aerial spores. The sporulation of the Streptomyces strains tested in complex medium appeared to be triggered by phosphate nutritional downshift, induced by addition of Ca2+ to the medium. Spore-shaped bodies were formed by S. lividans JI 1326 and S. coelicolor JI 2280 when grown in complex medium supplemented with Ca2+ and proline. The thermoresistance of these spore-shaped bodies differed from that of aerial spores.
authors.affiliation: Departamento de Microbiología, Facultad de Biología, Universidad de León, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Daza
authors.forename: J F
authors.initials: JF
authors.lastname: Martín
authors.forename: A
authors.initials: A
authors.lastname: Dominguez
authors.forename: J A
authors.initials: JA
authors.lastname: Gil
mesh_terms: D002122:Calcium Chloride / Q000494:pharmacology; D003470:Culture Media / Q000494:pharmacology; D006358:Hot Temperature; D008855:Microscopy, Electron, Scanning; D010710:Phosphates / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D017680:Potassium Compounds; D013170:Spores / Q000648:ultrastructure; D013302:Streptomyces / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D013305:Streptomyces griseus / Q000502:physiology
chemical_list: D003470:Culture Media; D010710:Phosphates; D017680:Potassium Compounds; C013216:potassium phosphate; D002122:Calcium Chloride; D011188:Potassium