• 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.

• Applied Biological Chemistry
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• v.33 no.4
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• pp.337-342
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• 1990

The pretense from Halobacterium sp. was purified by ethanol precipitation and gel filtration on Sephadex G-75 and G-100. The purified enzyme was found to be homogeneous by polyacrylamide gel electrophoresis It's specific activity was 364units/mg protein and yield was 14% of the total activity of the culture filtrate. The Km value against casein was determined to be $4.2{\times}10^{-4}M$ by Lineweaver-Burk plot The optimal temperature and pH for the enzyme activity were $35^{\circ}C$ and pH 8.0, respectively. The enzyme was stable from 5.0 to 11.0 at relatively wide range of pH but was inactivated at the temperature above $50^{\circ}C$. $Ca^{2+}$ and $Mg^{2+}$ appeared to react as activators whereas $Fe^{3+},\;Zn^{2+},\;Cu^{2+},\;Hg^{2+}\;and\;Cd^{2+}$ as inhibitors. The enzyme activity reduced with increasing the concentration of NaCl : the apparent activity with 2M NaCl was 65% as compared with that without the salt However the enzyme was unstable without salts : the activity was lost when dialyzed against distilled water for 2hr, whereas maintained against 0.1M solution of $CaCl_2$ for 6hr.

• Korean Journal of Microbiology
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• v.29 no.1
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• pp.56-62
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• 1991

Extremely halophilic bacteria isolated from salterns at Mado, Kyunggido, Korea, were identified and investigated on their salt requirements. The results have shown that six strains were identified to be belonged to the genus Halobacterium and three strains identified as the fenus Halococcus. Among them, the optimal NaCl concentration for growth of Halobacterium sp. EH10 was at 4.2M and no growth occurs below 2.0M NaCl. The strain, EH10, is nonmotile and showed acid production from glucose, fructose and maltose while H. salinarum is motile and does not produce acid from any carbohydrates. On the other hand, the strain EH10 does not utilize readily glucose while a number of sugars are readily utilized for growth with acid production by H. saccharovorum. Thus, the isolate, EH10, was classified into the genus Halobacterium and could be a novel species of the genus by its main morphological and physiological features including G+C content. The optimal temperature for growth of the isolate, EH10, was 50.deg.C. But this strain did not grow when NaCl was replaced with KCl.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.211-215
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• 1983

The changes of microflora during fermentation of low salted sardine were observed. The viable cell count in the low salt fermented sardine with $8\%\;or\;10\%$ salt showed lower than that of control ($20\%$ salt) during the fermentation period and it was considered that the microbial growth was controlled by adding ethanol, sorbitol and lactic acid. Among 48 strains isolated, 7 genus of bacteria and 1 genus of yeast were identified during the fermentation of sardine. The changes of microflora also occurred during fermentation depending on the salt levels in the product. Brevibacterium, Pseudomonas, Flavobacterium and Baciilus were detected at early stage of fermentation and they disappeared after 50 days fermentation from the product with $20\%$ salt and Halobacterium, Micrococcus, Pediococcus and Torulopsis were isolated, whereas Brevibacterium, Micrococcus and Pediococcus were isolated from the product with $8\%\;or\;10\%$ salt.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.40-47
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• 2005

In order to develop a multi-microbial biofungicide against several important plant pathogenic fungi, strains were isolated from the phtophthora blight suppressive red-pepper field soil of Gyeongsangbuk-do, Korea. Strains AY1, AY6, AB1, BB2 and F4, which had strong antagonistic ability against Phytophthota capsici and Fusarium oxysporum, were selected for their involvement with strains of biocontrol fungicide. There were no antagonism among the selected strains and were compatible for making the biofungicide. Their antagonistic mechanisms, except for strain BB2, were an antibiosis by the production of antibiotic, while BB2 produced not only an antibiotic but also cellulase as an antagonistic mechanism against blight causing P. capsici. They were identified as Halobacterium sp. AB1, Xenorhadus sp. AY1, Bacillus sp. AY6, Bacillus sp. BB2, Zymomonas sp. F4 by various cultural, biochemical test and $Biolog^{TM}$ System 4.0. The highest levels of antifungal antibiotic could be produced after 48 hrs of incubation under the optimal medium which were 0.1% galactose, 0.1% $NaNO_2$, 5 mM $Na_2{\cdot}HPO_4$ (pH 5.5). The cultured multi-microbial biofungicide showed strong biocontrol activity against bacterial wilt disease and fusarium wilt disease in cucumber and tomato fields.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.885-891
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• 1996

Various problems in fermented fish products have been a major obstacle to manufacture the product in large scale, which is mainly concerned with the food safety. In this review, salt-fermented anchovy was selected to elucidate the characteristics of microorganisms involved in fermentation; thereby, it is suggested for research areas to achieve the quality improvement of tile product. Different microorganisms were involved in fermentation of anchovy. Dominant species were reported to be Bacillus sp., Pseudomonas sp., and Micrococcus sp., other microorganisms were Vibro sp., Clostridim sp., Serratia sp., Achromobacter sp., Streptococcus sp., Breuibacterium sp., Halobacterium sp., Flavobacterium sp., Corynebacterium sp., Acinetobacter sp., Sarcina sp., Staphylococcus sp., Torulopsis sp., and Saccharomyces sp. To standardize the quality of fermented fish products, screening and isolation of promising microorganisms should be carried out to develop different types of products; at the same time, proper sanitation control should be employed to keep the commercial value of the product by prolonging the shelf life.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.517.3-518
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• 1986

국내 염장식품 및 염전으로부터 세균을 분리하여, 호염성 세균의 NaCl 농도에 따른 성장범위, 생리적 및 효소학적 특성을 조사하고자 했다. 염전으로부터 NaCl 20%배지에서 14주와 총 16종류의 젓갈류에서 NaCl 10% 배지로 56균주의 호염성 세균을 분리하여 0, 5, 10, 15, 20, 25% NaCl농도에서 성장률을 조사하고 최적온도 및 배지조성과 함께 동정에 필요한 생리실험을 하였다. 또한 세포의 효소로서 Lactate dehydrogenase, Glucokinase, Glucose-6-phosphate dehydrogenase, Alanine dehydrogenase, Isocitrate dehydrogenase 등의 특성도 조사하였다. 선별한 균주중 Acinetobacter sp, 등이 관찰 조사되었으며 최적 성장 NaCl농도는 10%이고, 최적온도는 3$0^{\circ}C$이며, 25% NaCl, 45$^{\circ}C$에서 자란 Halobacterium sp. 등이 분리되었다. 그중 Acinetobacter strain H6는 단백분해효소와 탄수화물 분해효소의 생성능이 15>10>20% NaCl순이며, 특히 Lactate dehydrogenase 활성은 2>3>1>OM NaCl 순으로 나타났고, NaCl 대신 KCl을 사용했을 때는 3>2>1> OM순으로 활성이 나타났다.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.456-459
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• 1992

The genes of Halohacteria. gvpD and gvpE. take part in formation of gas vesicle. These mRNA cause a lot of experimental prohlems due to its eharacteristic instahility in the analysis of transcripts. This study allowed easy cloning and sequencing of RNA hy substituting a stable complementary DNA for the mRNA of the genes for an analysis. The weak 111 RNA was reverse transcribed to DNA using reverse transcriptase. and was amplified using PCR method. The transcripts confirmed in this ~,tudy have not heen round in the northern hybridization covering almost all ranges of ORF of the gene. gvpD.