ROLE OF OXYGEN IN THE HIGH CELL YIELDS OF PSYCHROPHILES AND MESOPHILES AT LOW TEMPERATURES

Abstract

Sinclair , N. A. (Washington State University, Pullman) and J. L. Stokes . Role of oxygen in the high cell yields of psychrophiles and mesophiles at low temperatures. J. Bacteriol. 85: 164–167. 1963.—Psychrophilic and mesophilic bacteria produce maximal cell crops in stationary cultures at temperatures 10 to 20 C below those at which growth is most rapid. Our data indicate that O 2 is rapidly depleted to growth-limiting levels in stationary cultures, and that the higher cell yields at the lower temperatures are due simply to the increased solubility and, therefore, availability of O 2 . This conclusion is supported by the observation that equal cell crops are produced at high and low temperatures when cultures are vigorously aerated so that O 2 is not limiting, and also when facultative bacteria are grown anaerobically so that there is no O 2 to exert an effect.