Effect of hydrostatic pressure on succinic, formic, and malic dehydrogenases in Escherichia coli.

ZoBell and Morita (1957) demonstrated the existence of barophilic bacteria in various deeps and trenches of the Pacific and Indian Oceans where hydrostatic pressures up to 1,100 atm exist. However, the relationship between hydrostatic pressure and the activity of life in the deep sea is still unknown. Johnson et al. (1954), for convenience of discussion, divided hydrostatic pressure into moderate or high pressures (ca. 1 to 1,000 atm) and very high pressures (ca. 1,000 atm and above). The effect of very high pressures has been known to inactivate certain enzymes (Macheboeuf et al., 1933; Vignais et al., 1951; Matthews et al., 1940; Curl and Jansen, 1950a, 1950b). Using moderate pressures, Borrowman (1950) reported that hydrostatic pressures up to 700 atm at 30 C had no effect on the rate of formic dehydrogenase activity of Escherichia coli. In the latter work a pressure cylinder with optical windows was employed as well as cells of E. coli which were heated to 65 C for 5 min in order to inactivate as many interfering enzymes as possible. Since the cells were subjected to heat the "biological whole" was not represented. Morita and ZoBell (1956) studied the effect of hydrostatic pressure on the succinic dehydrogenase system in cells of E. coli, which had been previously subjected to pressure. These measurements were carried out by the Thunberg technique after the pressure was released to 1 atm. This paper deals with the effect of pressure on the rate of formic, succinic, and malic dehydrogenase by cells of E. coli during the time of compression.