• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.251-255
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• 1991

A 16 kilobase (kb) HindIII fragment of alkalophilic Bacillus sp. YC-335 containing a gene for xylanase synthesis was inserted at the HindIII site of pBR322 and cloned in Escherichia coli HB101. After subcloning of recombinant plasmid pYS52, the 1.5 kb fragment was found to code for xylanase activity, and the hybrid plasmid was named pYS55. The DNA insert of the plasmid was subjected to restriction enzyme mapping, which showed that pYS55 had single site for PuvII and SstI in the 1.5 kb insert fragment. Southern hybridization analysis revealed that the cloned gene was hybridized with chromosomal DNA from alkalophilic Bacillus sp. YC-335. About 64% of the enzyme activity was observed in the extracellular and periplasmic space of E. coli HB10l carrying pYS55.

• The Korean Journal of Food And Nutrition
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• v.7 no.1
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• pp.16-22
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• 1994

Xylanase from Bacillus sp. GS was purified through acetone precipitation, DEAE-Sephadex A-50 ion exchange chromatography and Sephadex G-100 gel filtration. The optimum reaction temperature of purified xylanase was 50t . Its optimum pH was between pH 6.0 and pH 6.5. This enzyme was stable below 5$0^{\circ}C$ for several hours and stable at between pH 5.5 and pH 8.0. The enzyme activity of xylanase was remarkably increased by Co++ and Cu++ ions. According to the study of hydrolysis mode of this enzyme, it was turned out to be ends type xylanase that can produce xylooligosaccharides, known as bifidogenic factor, from xylan.

• Journal of Life Science
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• v.8 no.4
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• pp.387-394
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• 1998

A thermophilic bacterium (strain DG0303) producing a thermostable $\alpha$-glucosidase was isolated from manure and identified as Bacillus sp. Strain DG0303 produced high level of $\alpha$-glucosidase compared with other thermophilic Bacillus strains. The cellular protein patterns were also compared with other Bacillus strains by sodium dodecyl sulfatepolyacrylamide gel electrophoresis(SDS-PAGE). On the basis of 16S rDNA analysis the Bacillus sp. DG0303 was found to be a member of Bacillus rDNA group 5. The optimum temperature for growth was 65$\circ$C and no growth was obtained at 40$\circ$C or 75$\circ$C. The optimum pH for growth was 5.5 to 8.5. $\alpha$-glucosidase activity was produced during growth and most activity was detected in the culture supernatant. The $\alpha$-glucosidase production was constitutive in the absence of carbohydrates. High level of enzyme activity was detected when the culture was grown on medium containing starch. Addition of glucose resulted in the repression of the $\alpha$-glucosidase production. The optimum pH and tempoerature for enzyme activity were pH 5.0 and 65$\circ$C, respectively. When analyzed by zymogram, the culture supernatant showed a single $\alpha$-glucosidase band with a molecular weight of approximately 60,000.

• Journal of Microbiology
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• v.34 no.4
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• pp.305-310
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• 1996

A microorganism producing carboxymethyl-cellulase (CMCase) was isolated from 300 soil and compost samples. The isolate was identified as Bacillus sp. by $Biolog^{TM}$ test and fatty acid analysis, and named as Bacillus sp. KD1014. The isolate could degrade, in addition to CMC, various kinds of polysaccharides such as levan, xylan, starch, and filter paper but hardly degrade microcrystalline Avicel. The optimum growth and CMCase production of the isolate was observed between 16-and 25 hr-culture at 45$^{\circ}C$ and pH 5.0. The maximum CMCase activity was observed at pH 4.5 and 6$0^{\circ}C$. The CMCase was found to bind to Avicel. The CMCase was internally cleaved as growth continued. When crude supernatant was used for activity staining, three major bands were detected on a native gel, however, only one major band was detected on a denaturating gel after removal of the detergent.

• Journal of Life Science
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• v.27 no.6
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• pp.688-693
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• 2017

Antifungal bacterium against Colletotrichum coccodes causing black dot disease of potatoes and anthracnose of tomatoes was isolated from sewage sludge. The isolate showed a 99% sequence homology of partial 16S rRNA of Bacillus methylotrophicus CBMB205 and Bacillus amyloliquefaciens subsp. plantarum FZB42. The isolate was identified as Bacillus sp. SW29-2, using the neighbor-joining phylogenetic tree, BlastN sequence analysis, and morphological and cultural characteristics. Bacillus sp. SW29-2 is an aerobic, Gram-positive, endospore-forming bacterium, of which the morphological and physiological characteristics were the same as those of type strain B. lichniformis CBMB205, except for the cell growth of over 4% NaCl. The cell growth of the temperature and the initial pH of the medium was shown at $18-47^{\circ}C$ (opt. ca. $38^{\circ}C$) and 3-9 (opt. ca. 6.0), respectively. The inhibition size (diameter) of Bacillus sp. SW29-2 against four strains of C. coccodes ranged from 23 to 29 mm. Also, the isolate showed antifungal activity against penicillium rot-causing Penicillium expansum in apples. Thus far, any report on the antifungal activity of Baciilus spp. against C. coccodes has not been found. These results suggest that the Bacillus sp. SW29-2 isolate could be used as a possible biocontrol agent against C. coccodes, and further applied to other plant pathogenic fungi.

• Journal of Life Science
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• v.22 no.6
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• pp.823-827
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• 2012

A bacterial strain producing a fibrinolytic enzyme, subtilisin CP-1, was isolated from Doen-Jang, a Korean traditional fermentation food. Based on the analysis of gene sequence of 16S rRNA and biochemical analysis, the strain was identified as Bacillus sp. and named as Bacillus sp. CP-1. To investigate the effect of the medium on the production of fibrinolytic enzyme from Bacillus sp. CP-1, two commercial bacterial culture media, tryptic soy broth (TSB) and Luria-Bertani (LB), were applied to the cultivation of Bacillus sp. CP-1. The strain secreted only one proteolytic enzyme (subtilisin CP-1) in the culture broth. The molecular weight of subtilisin CP-1 was estimated to be 28 kDa. Subtilisin CP-1 was optimally active at pH 9.0 and $45^{\circ}C$, and exhibited high specificity for Meo-Suc-Arg-Pro-Tyr-pNA (S-2586), a synthetic chromogenic substrate for chymotrypsin. The first eight amino acid residues of the N-terminal sequence of the enzyme are AQSVPYGI; this sequence is identical to that of subtilisin NAT and E.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.99-105
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• 2014

A Bacillus strain capable of hydrolyzing locust bean gum was isolated as a producer of extracellular mannanase by way of an enrichment culture in an acidic medium from homemade soybean pastes. The isolate YB-1401 showed a biochemical identity of 61.1% with Brevibacillus laterosporus, while the nucleotide sequence of its 16S rDNA had the highest similarity with that of Bacillus amyloliquefaciens. The mannanase productivity of the Bacillus sp. YB-1401 was drastically increased by mannans. Particularly, maximum mannanase productivity was reached at approximately 265 U/ml in LB medium supplemented with konjac glucomannan (4.0%). The mannanase was the most active at $55^{\circ}C$ and pH 5.5. Mannanase activity was completely maintained after pre-incubation at pH 3.5 to 11.0 for 1 h. The predominant products resulting from the mannanase hydrolysis were mannobiose and mannotriose for LBG, guar gum or mannooligosaccharides. A small amount of mannose was also detected in the hydrolyzates.

• Journal of Life Science
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• v.16 no.1
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• pp.120-125
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• 2006

To isolate and identify histamine degrading bacteria from Kwamegi, bacteria were screened with restriction media containing histamine. Ten strains were selected through morphological and biochemical identification procedure followed by comparison with DNA sequence of 16 rRNA gene. And also, these strains were confirmed by the histamine degrading assay such as turbidity and enzymatic assay. The results of identification are as followings : Ewingella americana B791, Arthrobacter sp. R45S, Halomonas marisflava, Psychrobacter sp. 9B-7, Bacillus sp. LMC 21002, Psychrohacter cibarius BC-220, Bacillus megaterium KL-197 were identified showing homology of $99\%,\;95\%,\;98\%,\;99\%,\;99\%,\;99\%\;and\;98\%$, respectively. Three strains remain unidentified. Arthrobacter sp. R45S, H. marisflava, Bacillus sp. LMG 21002, B. megaterium KL-197 showed histamine degrading activity, whereas, Psychrobacter sp. 9B-7 only showed weak activity. Three unidentified strains also have histamine degrading activity. In contrast, E. american B791 and p. cibarius JG-220 did not show any significant activity of histamine degradation. The strains isolated from this study showed relatively fast growth rate and histamine degrading rate as compared to those from salted mackerel.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.193-199
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• 2009

A bacterium producing the halotolerant extracellular protease was isolated from squid jeotgal, and was identified as Bacillus sp. SJ-10 based on morphological, physiological and biochemical characteristics, as well as phylogenetic analysis using 16S rRNA gene sequence. The strain grew at $20^{\circ}C\sim55^{\circ}C$, pH 5~8, and 0%~14% NaCl and optimal growth conditions were $35{\pm}5^{\circ}C$, pH 7, and 5% NaCl. The major cellular fatty acids were anteiso-$C_{15:0}$, anteiso-$C_{17:0}$, and $C_{16:0}$ DNA G+C content was 50.58 mol% and menaquinone consisted of MK-7 Phylogenic analysis based on the 16S rRNA gene sequence indicated that SJ-10T belongs to the genus Bacillus. About 40 kDa of the salt-tolerant protease was purified by 40% ammonium sulfate saturation and Mono Q column chromatography. The optimal activity of the protease was pH 8 and stable at pH 5~10. The optimum temperature and NaCl concentration were $35{\pm}5^{\circ}C$ and $5{\pm}1%$, respectively.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.167-174
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• 1991

Cultural conditions for the biopolymer production by an alkali tolerant Bacillus sp. isolated from soil were investigated and determination of optimal conditions was carried out by response surface method. The maximal production of biopolymer was obtained after cultivation at $30^{\circ}C$ for 36hrs in the mixture of 8% soluble starch, 0.75% yeast extract, 0.1% $NaNO_3$, 0.05% $MgSO_4\;7H_2O$ and 1% $Na_2CO_3$ adjusted to pH 10. Under these conditions, about 44 g/l of biopolymer were produced. From the results of response surface analysis, optimal condition for the production of biopolymer were obtained at stationary point with 15.16 of C/N ratio, $34.62^{\circ}C$ of temperature and 9.50 of pH. On the basis of these conditions, it was estimated that 66.84 g/l of the biopolymer could be produced.