ORGANIC SOLVENT-TOLERANT BACTERIUM WHICH SECRETES AN ORGANIC SOLVENT-STABLE PROTEOLYTIC-ENZYME

A bacterial strain which can be grown in a medium containing organic s olvents and can secrete a proteolytic enzyme was isolated and identifi ed as Pseudomonas aeruginosa. The strain was derived by the following two-step procedures: high proteolytic enzyme producers were first isol ated by the usual method, and then the organic solvent-tolerant microo rganism was selected from these high-rate proteolytic enzyme producers . The proteolytic activity of the supernatant of the culture was stabl e in the presence of various organic solvents, The stability of the en zyme in the presence of organic solvents, of which the values of the l ogarithm of the partition coefficient (log P) were equal to or more th an 3.2, was almost the same as that in the absence of organic solvents . It is expected that both the solvent-tolerant microorganism and the solvent-stable enzyme produced by this strain can be used as catalysts for reactions in the presence of organic solvents.