• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.128-128
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• 2003

• Proceedings of the Korean Society of Life Science Conference
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• 2002.03a
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• pp.42-42
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• 2002

• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.129-129
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• 2003

• Applied Biological Chemistry
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• v.34 no.4
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• pp.307-311
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• 1991

A moderate halophile, ES 10 which produces a high level of alkaline protease was isolated from the salted anchovies and indentified as a strain of Halomonas sp. The optimum growth of the Halomonas sp. was revealed in the presence of 2 M NaCl and its growth rate in the Temporary Synthetic Medium was increased by adding DL-alanine, but inhibited by adding L-proline. The concentration of $Na^+$, $K^+$ and $Mg^{2+}$ in the cell mass of the Halomonas sp. ES 10 was 5-, 25- and 35-fold higher by dry weight basis, respectively than those of B. subtilis or E. coli. Norberg and Hofsten medium with 1 M NaCl was selected as the best medium for producing high level of alkaline protease. The optimum temperature for the growth and protease production was equally $20^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.21 no.1
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• pp.11-21
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• 1994

The halophile, Micrococcus sp. which produces RNase was isolated from salted and fermented food. The optimum growth condition of the Micrococcus sp. in pH 7.0 of complex medium containing 2M NaCl, and at $35^{\circ}C$. Optimum condition for enzyme production by this strain was when it was grown in the CM medium, containing 2% yeast extract, 1.5% casamino acid and 2M NaCl in the initial pH 8.5 for 2 days. The maximal RNase activity was observed at pH 8.0 and $55^{\circ}C$. The Km value for RNA was determined to be 5mg/ml by Lineweaver-Burk plot. The RNase activity in the absence of NaCl was maximum, but it was completely lost by adding of 1.25M NaCl and it was increased above 1.25M to 2.5M NaCl. When 2.5M NaCl was added, the activity of RNase showed 45% of maximum value.

• Journal of Life Science
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• v.20 no.2
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• pp.183-189
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• 2010

A fibrinolytic enzyme producing Bacillus sp. J-19 was isolated from the popular Korean seasoning, pickled anchovy. The fibrinolytic enzyme was purified to homogeneity by chromatographic methods including ethanol precipitation and gel-filtration using Sephadex G-50. Compared to the crude enzyme extract, the specific activity of the enzyme increased 1021-fold with a recovery of 23%. The purified enzyme was estimated to be approximately 45 kDa by SDS-PAGE. Especially, the amidolytic activity in the presence of the synthetic substrate for serine protease (H-D-Ile-Pro-Arg-pNA, S-2288) represented approximately 17 U/mg. In addition, more than the 60% activity of the 45 kDa fibrinolytic activity was maintained in the presence of up to 30% (w/v) sodium chloride. These findings could provide a unique fibrinolytic enzyme, leading to a potential thrombolytic agent.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.237-241
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• 1992

The protease from Halomonas sp. ES 10 was purified by methanol precipitation, gel filtration on Sephadex G-150 and G-200, and ion exchange chromatography on DEAE-Sephadex A-50. The purified enzyme was found to be homogeneous by polyacrylamide gel electrophoresis. The specific activity of purified enzyme was 1,014 units/mg protein, and the yield of the total activity from the culture filtrate was 7%. The optimal temperature and pH for the enzyme activity were $35^{\circ}C$, and pH 11.0, respectively. And the enzyme was stable in the range of $pH\;7.5{\sim}11.0$. The residual activity of the enzyme was 70%, when the enzyme was incubated at $50^{\circ}C$ for 40 min. The Km value of the enzyme was 7.4 mg/ml to milk casein. $Li^+$, $Ca^{2+}$, SDS and Tween 80 were appeared to activators, whereas $Hg^{2+}$ and EDTA to inhibitors. The addition of DFP and PMSF showed the relative enzyme activities of 63% and 107%, respectively, suggesting that the enzyme may not belong to serine type protease. When the alkaline protease was treated with 0.5 M and 1 M NaCl, the relative enzyme activities were 95% and 65%, respectively. This enzyme showed 20% and 15% higher enzyme activity than that of Aspergillus oryzae (Sigma Chemical Company product, P4755) in the presence of 0.5 M and 1 M NaCl.

• Applied Biological Chemistry
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• v.33 no.3
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• pp.247-251
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• 1990

A bacterial strain which produce a high level of protease was isolated from a commercial salted fish, squid jetkal. This strain was identified as a strain belong to the genus Halobacterium and was found to be extremely halophilic : more than 2.0M of sodium chloride was required for the growth. The protease production by the strain was maximized when grown on Norberg & Hofsten medium containing 4.5M sodium chloride, 1.5% gelatin and 0.4% yeast extract (initial pH 7.0) for 108hrs at $38^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.19 no.2
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• pp.153-157
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• 1991

Intracellular enzymes of an extreme halophilic bacterium, Halobacterium sp. HE10, isolated from a saltern in Korea was investigated. The membrane-bound enzyme, NADH dehydrogenase, involved in electron transport system was stimulated by the addition of 2.0 M NaCl. The respiratory enzyme activities such as NADH oxidase and NADH dehydrogenase was decreased on removal of $Na^+$ ion and restored when replaced with cations like $K^+$, $Li^+$and $NH_{4}^{+}$ ions. Furthermore, their activities were affected by the anions such like carbonate, acetate, sulfate, chloride and nitrate at the presence of $Na^+$ion. Lactate dehydrogenase activity was highest at the asturated solution of NaCl and isocitrate dehydrogenase activity was a maximum level at 1.0 M NaCl. These results suggested that the enzyme activites of the respiratory chain in Halobacterium sp. EH10 was stimulated by the presence of $Na^+$ ion.

• Microbiology and Biotechnology Letters
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• v.15 no.5
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• pp.301-305
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• 1987

Moderate halophilic bacteria isolated from several kinds of salted and fermented sea foods (jeotkal) collected from commercial market were identified and investigated on their selt requirements. It was confirmed that the isolates were dominantly moderate halophiles according to their NaCl requirement to grow. And their salt requirements in their growth have been examined for Na, K, Ni and mg ions. Among them, the most dominant and distinctive three strains in protease pro-duction have been examined and two of them identified to be halophilic Flavobacterium sp., and the other one to be halophilic Pseudomonas sp..1'heir optimum growth was observed at 3$0^{\circ}C$ and at 10 percent of NaCl.