• Journal of Mushroom
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• v.19 no.3
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• pp.134-139
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• 2021

A diverse group of plant-growth promoting bacteria were isolated in button mushroom (Agaricus bisporus) media to investigate the plant-growth promoting traits of compounds including indole acetic acid (IAA), ammonia, 1-aminocyclopropane-1-carboxylic acid deaminase, siderophore, and hydrogen cyanide. Twenty-one bacterial strains showing positive effects for all the test traits were selected and classified to confirm bacterial diversity in the media habitat. Plant-growth promoting traits of the isolates were also assessed. All strains produced IAA ranging from 20 ㎍/mL to 250 ㎍/mL. Most of the isolates produced more than 80% siderophore. Four strains (Pantoea sp., PSB-08, Bacillus sp., PSB-13, Pseudomonas sp., PSB-17, and Enterobacter sp., PSB-21) showed outstanding performances for all the tested traits. In a bioassay of these four strains using mung bean plant, the best growth performances (23.16 cm, 22.98 cm, 2.27 g/plant, and 1.83 g/plant for shoot length, root length, shoot dry weight, and root dry weight, respectively) were obtained from the plants co-inoculated with Bacillus sp., PSB-13. The resultant data indicate that button mushroom media have got a diverse group of bacteria with plant growth promoting abilities. Thus, the media could be a good recycling resource for using to an effective bio-fertilizer.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.256-263
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• 2012

A strain of bacterium producing antifungal antibiotic was isolated and identification of the strain was attempted. We could identify the bacterium as being a Bacillus sp., based on morphological observation, physiological characteristics, and 16S rDNA sequence analysis, thus leading us to designate the strain as Bacillus sp. AH-E-1. The strain showed potent antibiotic activity against phytopathogenic and human pathogenic fungi by inducing mycelial distortion and swelling and inhibiting spore germination. The antibiotic metabolite produced by the strain demonstrated excellent thermal and pH (2-11) stability, but was labile to autoclaving. From these results, we could find a broader antifungal activity of Bacillus genus. Isolation and characterization of the active agent produced by the strain are under progress.

• Journal of Life Science
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• v.10 no.1
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• pp.1-5
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• 2000

Pectinase was isolated from culture medium of Bacillus sp. BS-214 and purified 105-fold with 3.4% yield by ammonium sulfate precipitation, gel filteration using Sephadex G-75 and DEAE-cellulose followed by gel filteration through Sephadex G-100. The molecular weight of the purified enzyme was estimated to be about 43 kDa on SDS-PAGE and by gel filtration, indicating that the enzyme is a monomer. the optium pH and temperature of the enzyme were 9.0 and 55$^{\circ}C$, respectively. the enzyme was stable at 60$^{\circ}C$ for 30min and in a pH range from 7.5 to 10.5 for 12 h ant 4$^{\circ}C$. The enzyme activity was highly enhanced by Ca2+, and also K+, Li+ and Na+showed a positive effect, while stongly inhibited by Zn2+ and Hg2+.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.293-298
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• 2005

Lab scale experimental study was carried out for SBR process, to investigate the effects of influent ship sewage organic compound removal and Bacillus sp. state on design parameters. This process was able to remove nitrogen and phosphorus as well as organic matter efficiently. More than 95% of chemical oxygen demand(COD) were removed. In addition, about 97% of total nitrogen (T-N) was reduced. The total phosphorus(T-P) reduction averaged 93%. The performance load of SBR process was shown to be 0.095kg ${\cdot}$ TOC/$m^{3}$ ${\cdot}$ day. The pH was decreased from 8.1 to 7.0 within 30 min and increased to 7.3 at the end of anoxic stage, and these phenomena were explained. The sluge produced in the SBR process is characterized by low generation rate (about 0.36kg ${\cdot}$ MLSS/kg ${\cdot}$ TOC) and excellent settleability. The number of Bacillus sp. in the SBR was 24.2%, indicating that Bacillus sp. was a predominant species in the reactor.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.1-7
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• 1991

A bacterial strain No.71, which produced alkaline protease, was isolated from soil and identified to the genus Bacillus. With the successive mutation, a mutant strain No. M-71, having high alkaline protease productivity, was obtanined from the parental strain No 71. Alkaline protease productivity of mutant strain No. M-71 was about 50 times as much as that of the parental strain No.71. The enzyme preparations showed strong activities toward casein, the optimum pH being 11.0 and the optimum temperature about $55^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.191-196
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• 1996

The bacteriolytic enzyme produced from Bacillus subtilis SH-1 was purified and characterized, and its molecular weight was determined. The bacteriolytic enzyme activity was increased about 66.5 times via purification with recovery yield of 18.5%. The optimum pH and temperature of this enzyme were 9.0 and 50$\circ$C. The enzyme was stable within a pH range of 6.0-10.0 and unstable above 60 . The molecular weight of the enzyme was estimated to be 23,000 dalton in a form of monomer with no other subunits. Effect of the enzyme on the lysis of bacteria engaged in food posion was tested. The lysis degree was below 31% against Gram negative bacteria and above 48% in Gram positive bacteria. The values higher than 73% were obtained against Vibrio sp. and Listeria sp. As the turbidity of dissolved peptidoglycan clecreases, the free amino group levels were increased. And, based on hydrolysis of casein, this enzyme was thought to be an endopeptidase.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.206-212
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• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• Microbiology and Biotechnology Letters
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• v.34 no.1
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• pp.7-14
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• 2006

Feather, generated in large quantities as a byproduct of commercial poultry processing, is almost pure keratin, which is not easily degradable by common professes. Four strains, SMMJ-2, FL-3, NO-4 and RM-12 were isolated from soil for production of extracellular keratinolytic protease. They were identified as Bacillus sp. based on their morphological and physiological characteristics. They shown high protease activity on 5.0% skim milk agar medium and produced a substrate like mucoid on keratin agar medium. Bacillus sp. SMMJ-2 had a faster production time for producing keratinolytic protease than other strains. This strain did not completely degrade whole chicken feather for five days in basal medium but completely degraded whole chicken feather when supplied with nitrogen source for 40hours in keratinolytic producing medium ($0.7%\;K_{2}HPO_{4},\;0.2%\;KH_{2}PO_{4},\;0.1%$ fructose, 1.2% whole chicken feather, $0.01%\;Na_{2}CO_3$, pH 7.0). When supplied with chicken feather as nitrogen source, keratinolytic protease activity was 89 units/ml/min. When soybean meal was used as nitrogen source, the keratinolytic protease production reached a maximum of 106 units/ml/min after 48 hours under $30^{\circ}C$, 180 agitation. To isolate the keratinolytic protease, the culture filtrate was precipitated with $(NH_4)_{2}SO_4$ and acetone. The recovery rate of keratinolytic protease was about 96% after treatment with 50% acetone. The enzyme was stable in the range of $30{\sim}50^{\circ}C$ and pH $6.0{\sim}12.0$.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.507-511
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• 1995

In an attempt to improve the productivity of ${\beta}-galactosidase$ from Bacillus sp. A1, which was isolated from soil and has remarkably higher transgalactosylation activity than lactose hydrolysis activity, a chemical mutation procedure using N-methyl-N'-nitro-N-nitrosoguanidine followed by selection was conducted. The final selection, designated as Bacillus sp. A4442, turned out to show a substantially increased enzyme productivity. Catabolite repression by glucose and lactose requirement as an inducer for the enzyme biosynthesis, which were shown in the parent strain, was markedly diminished; instead it was found out that galactose acts as another inducer. Because pH of medium, one of the most important factors for cell growth as well as enzyme production, is closely related with the sugar concentration during culture, it was kept in the optimum range of $6.5{\sim}7.5$; for this the initial glucose concentration was adjusted to be 0.5% which was thereafter maintained by the controlled pumping-in of lactose using the pH-stat technique. By doing so, we were able to increase the productivity of ${\beta}-galactosidase$ with high transgalactosylation activity up to $44\;unit/m{\ell}-broth$.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.67-72
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• 2006

The nucleotide sequence of the cloned cellulolytic xylanase gene (bglBC2) from B. circulans ATCC21367 was determined. bglBC2 consists of an 1,224 bp open reading frame (ORF) coding for a polypeptide of 407 amino acids with a deduced molecular weight of 45 kDa. The Shine-Dalgarno (SD) sequence (5'-AAAGGAG-3') was found 9 bp upstream of the initiation codon, ATG. A promoter region corresponding closely to the B. subtilis consensus sequence (-35: TTGACA,-10: TATAAT) was detected, the putative -35 and -10 sequences of which were TTTACA and TATACT, respectively. The deduced amino acid sequence of the cellulolytic xylanase showed 97% homology with that of the alkaline $endo-\beta-1,4-glucanase$ from B. circulans KSM-N257, 75% homology with that of the $endo-\beta-1,3-1,4-glucanase$ from B. circulans WL-12, and 45% homology with that of the $endo-\beta-1,4-glucanase$ (cellulase) from Bacillus sp. KSM-330. The bglBC2 sequence was deposited in Gen-Bank under the accession number AY269256.