• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.160-165
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• 1996

An alkalophilic bacterium producing alkaline protease(s) was isolated from soil. It was a Gram-positive, non-sporulating, immotile, irregular rod, strictly aerobic, and weak acid-forming bacterium. The morphological, physiological, and biochemical characteristics of the isolate resembled those of the Coryneform bacteria. However, there was not any species within this genera to which this microorganism can be closely matched. Therefore, it is provisionally identified as a Coryneform bacterium TU-19.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.337-341
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• 1998

The morphological and cultural characteristics of alkalophilic Coryneform bacteria TU-19 were investigated at various pHs. This bacterium showed normal growth pattern at $pH\;9.0{\sim}10.0$, but the cell growth was completely inhibited at extreme pH (12.0 or more). Interestingly, at pH 8.0 the morphology of the bacterial cells seems to form convoluted filaments during the exponential growth phase while at pH 10.0, the optimal pH for the growth of this organism, the bacteria grew with variable paired or single forms, and straight rods during growth stages. Growing in alkaline media $(pH\;9.0{\sim}11.0)$, it adjusted the pH of the culture media to around pH 8.5 by itself.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.534-540
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• 1995

Alkalophilic coryneform bacteria TU-19 isolated from soil extracellularly produced at least three proteases (Protease I, II, and III). Investigating the cultural conditions related to the enzyme production of this bacterial cell, the optimum pH and temperature were 10.0 and $30^{\circ}C$, respectively. In order to purify these enzymes from the 2 day culture broth ammonium sulfate fractionation, gel filtration and QAE-Sephadex column chromatography were performed step by step. And then these three proteases were purified to near homogeneity by judging from SDS-PAGE pattern, and had the molecular weights of 120, 80, and 45 kilodaltons, respectively. The optimum pH and temperature for the enzyme activity of Protease I and II were 10.5 and $45^{\circ}C$, respectively, and Protease II were 11.0 and $50^{\circ}C$. And the enzymes were completely inhibited by PMSF suggesting serine protease, but not affected by pCMB. 1,10-phenanthroline, IAA, and EDTA.