AMMONIA PRODUCTION FROM VARIOUS SUBSTRATES BY PREVIOUSLY PRESSURIZED CELLS OF ESCHERICHIA COLI

For convenience of discussion Johnson et al. (1954) divided hydrostatic pressure into moderate or high pressure ( ca 1 to 1,000 atm) and very high pressure (ca 1,000 atm and above). It is known that very high pressures denature proteins (Bridgeman, 1914; Basset et al., 1933a; Grant et al., 1941), inactivate enzymes (Matthews et al., 1940; Curl and Jansen, 1950a, 1950b; Vignais et al., 1951), inactivate certain bacteria and viruses (Roger, 1895; Larson et al., 1918; Giddings et al., 1929; Basset et al., 1933b, 1935, and 1938; Luyet, 1937a, 1937b). According to Johnson et al. (1954) the effects of moderate hydrostatic pressure on physiological activities were frequently reversible, sometimes quantitatively so, as soon as the pressure was released. Morita and ZoBell (1956) observed that the "biological whole" lyophilized cells of Escherichia coli previously pressurized to hydrostatic pressure underwent an inactivation of their succinic dehydrogenase system. They observed that the longer the pressurization, the more inactivation of the dehydrogenase system and that the inactivating effects of pressure were most pronounced at temperatures either above or below the organism's optimum for multiplication. This paper deals with the production of ammonia from different substrates by washed cells previously pressurized to 1, 200, 600, and 1,000 atm for 3 hr at 30 C.