title: [Influence of physical parameters on the production of streptococcal extracellular proteins in cultures with stabilized pH. I. Communication: pH-dependence of extracellular protein production (author's transl)].
abstract: The influence of the pH of the medium on growth and production of extracellular proteins was examined in a group C streptococcus (SA. equisimilis strain H 46 A). The pH values employed ranged from 5.0 to 8.5 and the analytical methods used included the determination of enzyme activities, isoelectric focusing, crossed-immunoelectrophoresis, and SDS electrophoresis. The strain is able to grow in the entire pH range used, with maximum growth occurring at pH 6.5. The amount of extracellular proteins elaborated depended on both the pH of the medium and the biomass produced. A specific pH range was defined for optimum production of all enzymes examined. With the exception of streptodornase and NAD-glycohydrolase, the pH optimum for product formation was generally in the neutral and weakly alkaline range. Active proteinase was formed only a pH 6.0, leading to gross degradation of most of the other proteins in the culture medium. At pH values ranging from 6.5 to 7.5, isoelectric focusing revealed the production of 28 different extracellular proteins, and crossed immunoelectrophoresis demonstrated 30 to 32 antigens. The number of extracellular products produced greatly declined at pH values above and below this range. Under optimum conditions, the main extracellular product at H 46 A was streptokinase, followed by deoxyribonuclease A.
mesh_terms: D000942:Antigens, Bacterial / Q000032:analysis; D001426:Bacterial Proteins / Q000096:biosynthesis*; D003378:Counterimmunoelectrophoresis; D003470:Culture Media; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D013291:Streptococcus / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D003470:Culture Media
vernacular_title: Einfluss physikalischer Parameter auf die Bildung extrazellulärer Streptokokkenproteine in pH-stabilisierten Kulturen. I. Mitteilung: Die Rolle des pH-Wertes bei der Bildung von extrazellulären Streptokokkenprodukten.