[Respiration of an obligate methylotroph in the presence of various substrates].

Respiration of the cells of Methylococcus ucrainicus, strain 21, cultivated in the atmosphere of methane, is stimulated by methanol, formaldehyde, formate, n-alcohols, and allyl alcohol. The rate of oxygen assimilation is lower in the presence of isopropanol, isobutanol, propane, butane, maltose, and some organic acids (acetate, fumarate, citrate, succinate). The Michaelis constant for methanol is 88 mcM. Oxidation of methane, methanol, formaldehyde, and formate by the bacterium is inhibited by cyanide, hydroxylamine, and azide. The rate of oxygen assimilation by the cells in the presence of methane and other C1-compounds did not decrease after the suspension had been stored at 4 degrees C during four months and longer.