THE PREDOMINANT BACTERIA IN NATURAL ZOOGLOEAL COLONIES: II. PHYSIOLOGY AND NUTRITION

Abstract

Strains of Zoogloea were investigated regarding their physiological attributes. Growth occurred from 9 C to 37 C although some strains could not grow at the lower temperature. Optimum temperature and pH for growth initiation was estimated to be near 28 C and pH 7.0, respectively. Zoogloea cannot grow an-aerobically but may survive anaerobic conditions for at least 24 days. Strains were intolerant of NaCl above the region of physiological saline and tolerant to high levels of ammonium ion. A total of 65 strains were tested for growth on many nutritional compounds in a mineral salts medium supplemented with vitamin B12and a trace of yeast autolysate. As sole carbon sources, amygdalin, starch, inulin, and certain primary alcohols, saturated fatty acids, and Krebs intermediates supported the growth of most strains. Aspartic and glutamic acids and asparagin were available as sole carbon and nitrogen sources to most strains.