• Journal of Life Science
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• v.2 no.4
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• pp.232-239
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• 1992

UDP_GlcNAc is metabolized to form vegetative cell wall, cortical peptidoglycans, and outermost layer consisting of galactosamine-6-phosphate ploysaccharide in life cycle of Bacillus megaterium. To obtain a better understanding of the UDP-GlcNAc regulation, we examined the activity of the common first enzyme for the synthesis of nucleotide precursors of peptidoglycans, enoylpyruvate transferase by newly developed method. Both the specific and the total activity decreased after the end of exponential growth followed by and increase from t5 but decreased again parallel to the appearance of the activity of UDP_GlcNAc-4-epimerase. Antibody specificity to anti-transferase IgG and the elution profile on DEAE-Sepharose revealed that B. megaterium has at least two enoylpyruvate transferase isozymes, and UDP_GlcNAc was metabolized to vegetative cell wall and cortical peptidoglycan by each isozme in exponential growth and in sporulation, respectively in life cycle.

• Journal of Life Science
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• v.11 no.4
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• pp.304-310
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• 2001

In order to produce a high quality and functional black bean Chungkugjang, a bacterium which has potent enzyme activities(protease:124.8 U/$m\ell$, $\alpha$-amylase: 78.2U/$m\ell$, glucoamylase; 13.9U/$m\ell$, ), was isolated by using the halo zone method and identified by morphological, cultural and biochemical properties, and then finally confirmed by GP-microplate identification system as Bacillus megatrium SMY-212. The isolated SMY-212 system was also high in the formation of mucoid material and fibrinolytic activity.

• Korean Journal of Environmental Biology
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• v.21 no.4
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• pp.358-365
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• 2003

A bacterial strain capable of producing a novel bioflocculant was isolated from a biofilm sample and identified as Bacillus megaterium G31. The highest biopolymer yield was achieved when the organism was cultivated in a medium containing acetate as the sole carbon source and ($NH_4)_2HPO_4$as the nitrogen source. In kaolin suspension, the flocculating activity was highest at 170 mg I$^{-1}$ and decreased at the higher bioflocculant concentrations. The crude bioflocculant produced by the organism was purified by ethanol precipitation and gel permeation chromatography. The FTIR spectrum of the purified bioflocculant revealed that the bioflocculant might be a heterogeneous polysaccharide composed of hexosamines and neutral sugars. The analysis of sugar components of the bioflocculant using high performance anion-exchange chromatography showed that the sugar constituents of the bioflocculant were glucosamine, fucose, galactosamine, galactose, glucose, mannose in approximate molar ratio of 4 : 1 : 6 : 3 : 8 : 19. Its flocculating activity was stimulated by various cations. The bioflocculant was thermo-stable and retained 64% of its original activity after heating at $100^{\circ}C$ for 50 min.

• Journal of environmental and Sanitary engineering
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• v.23 no.1
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• pp.25-31
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• 2008

A bacterial strain, Bacillus megaterium L-49 has been isolated and identified that produces alkaline ${\alpha}$-amylase. The cell is ellipsoidal, about $1.0-1.2{\times}3.0-3.6{\mu}m$ in diameter, Gram-positive, motile, and central partial central. Growth occurs in media containing 7% of NaCl. This strain could utilize D-glucose, lactose, xylose, sucrose, mannose, and maltose, and but it does not utilize D-fructose, and glycogen. Among the various concentrations of saturated ammonium sulfate, the retractation ratio in range of 70 to 100% was about 93%. However, in the case of acetone, it was about 98.7%. EDTA has activating effect and Ca2+ has no effect on alkaline ${\alpha}$-amylase activity. The alkaline ${\alpha}$-amylase has low thermal stability. The optimal temperature for reaction is $50^{\circ}C$. The alkaline ${\alpha}$-amylase activity maintained stabilizing at pH 6-11 and the optimal pH for reaction was 9-10.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.147-151
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• 2000

A gene, nprM, from Bacillus megaterium ATCC 14945 was obtained by PCR using primers synthesized based on two nprM sequences from two different strains, and cloned into Escherichia coli. The gene nprM encoded an extracellular neutral protease, and the molecular mass of the expressed enzyme was estimated to be approximately 36kDa on a denaturating gel. The enzyme was activated by $Ca^{2+}$, and the optimum concentration of $Ca^{2+}$ was 5 mM. The enzyme was inhibited by EDTA but not by PMSF. The optimal pH and temperature of the cloned enzyme were $50^{\circ}C and pH 7.5-8.0, respectively, and were similar to those of the enzyme from the gene gonor cell. The cloned NprM caused internal cleavage of the native endoglucanase of B. subtilis BSE616 as a model foregin protein, and resulted in a small truncated but still active endoglucanase.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.203-208
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• 2000

A Baczllus circdans KCTC3004 $\alpha$-amylase gene contained in a recombinant plasmid pAL850 was transferred into a new shuttle vector plasmid pALSIlI by ligating linearlzed DNAs of pUC19 and pUB110. B. subtilis RM125 and B. megatenurn ATCC14945 transfonned with pALS111 produced the $\alpha$-amylase substantially Most of the enzyme was produced during the exponential growth period. The maxiinurn activities of the $\alpha$-amylase produced by the Bucillus transformants were compared with that of the B. circulans gene donor strain. The B. subtilis RM125(pALS111) enzyme showed the actlvicy 95 times higher than that of the gene donor cells, followed by the B, nzegaterium ATCC14945(pALSlll) enzyme with activity 34 limes higher than that of the gene donor cells. While E coli secreted about 10% of the produced enzyme, B. subtilis excreted the enzyme inlo the medium wholly and B. megaterirun about 98% ofthe total product. The plasmid pALSI11 was quite stable inB. nzegaterium (92%), inoderately stable in B. subtilis (76%), but was unstable in E. coli (38%). The SDS-PAGE and zymogram of this enzyme produced in E. coli(pALS111), B. subtilis( pALS111) or B. megateril~m (pALS111) indicated a molecular weight of 55,000. The enzymes overproduced in three different host cells hydrolyzed starch to produce mainly maltoaiose and mallooligosaccharides.

• Journal of the Korean Applied Science and Technology
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• v.37 no.6
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• pp.1535-1544
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• 2020

The primary objective of this study was to isolate and identify amine oxidase-producing probiotic Bacillus strains from traditional fermented soybean paste. Biogenic amines (BA)-forming bacteria isolated from the samples were identified as Bacillus sp. TS09, Bacillus licheniformis TS17, Bacillus subtilis TS19, Bacillus cereus TS23, Bacillus sp. TS30, Bacillus megaterium TS31, B. subtilis TS44, Bacillus coagulans TS46 and Bacillus amyloliquefaciens TS59. Meanwhile, B. subtilis TS04 and TS50 isolated from the same samples exhibited good probiotic properties, including the tolerance to artificial gastric juice and bile salts, the adhesion to intestinal epithelial cells, and the production of bacteriocin(s) active against BA-forming bacteria (Bacillus sp. TS30 and B. subtilis TS44). In addition, the amine oxidase produced by B. subtilis TS04 and TS50 significantly decreased the formation of BA, especially cadaverine, putrescine, and tyramine, therefore, these strains could be considered good potential probiotic candidates to prevent or reduce BA accumulation in food products.

• Journal of Life Science
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• v.18 no.12
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• pp.1625-1630
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• 2008

A microorganism capable of producing high level of poly-3-hydoxybutyrate (PHB) from xylose was isolated from soil. The isolated strain J-65 was identified as Bacillus megaterium based on the morphological, biochemical and molecular biological characteristics. The optimum temperature and pH for the growth of B. megaterium J-65 were $37^{\circ}C$ and 8.0, respectively. The optimum medium composition for the cell growth was 2% xylose, 0.25% $(NH_4)_2SO_4$, 0.3% $Na_2HPO_4{\cdot}12H_2O$, and 0.1% $KH_2PO_4$. The optimum condition for PHB accumulation was same to the optimum condition for cell growth. Copolymer of ${\beta}$-hydroxybutyric and ${\beta}$-hydroxyvaleric acid was produced when propionic acid was added to shake flasks containing 20 g/l of xylose. Fermenter culture was carried out to produce the high concentration of PHB. In batch culture, cell mass was 9.82 g/l and PHB content was 35% of dry cell weight. PHB produced by B. megaterium J-65 was identified as homopolymer of 3-hydoxybutyric acid by GC and NMR.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.1
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• pp.8-14
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• 2005

Mass culturing of two beneficial organisms used as biofertilizers for crops would reduce the risks in production and minimize the capital involved and this demands appropriate media that supports both organism and also selection of organisms that are not antagonistic to each other. A study was initiated to culture a nitrogen fixer (Rhizobium) and phosphate solubilizer (Bacillus megaterium) in a single medium and to study their growth patterns and shelf life in carrier. The growth of Rhizobium and Bacillus megaterium was assessed in different media and a slight modification in the traditional yeast extract mannitol media promoted the growth of both the organisms. The growth of the individual organisms in the modified medium was assessed by estimating the population at regular intervals and compared to their original medium. Maximum population of Rhizobium and phosphobacteria was at 60 hr when the phosphiobacteria inoculation of later was after 48 hr of Rhizobium inoculation. The shelf life of the individual inoculants in the inoculant containing both the organism in a sterile carrier base revealed no significant differences compared to individual organisms inoculated in a sterilized carrier. The population of both organisms in carrier based mixed inoculant remained at $10^8$ cells till 90 days.

• Journal of Life Science
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• v.14 no.2
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• pp.229-234
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• 2004

Feathers, which are almost pure keratin protein, are produced in large amounts as a waste by-product at poultry-processing plants. Keratinolytic enzymes may have important uses in biotechnological processes involving keratin-containing wastes from poultry and leather processes. In this study, screening and identification of keratin-degrading bacteria were investigated. Five keratin-degrading bacterial strains (F3-1, F3-4, F7-1, C1-1, C1-2) were isolated from compost and decayed chicken feather. On the basis of morphological, physiological studies, and Biolog system, all isolates were identified as the genus Bacillus. Among them, the strain F7-1 had the highest feather-degrading activity and was selected for further taxonomical study. Phylogenetic analysis of strain F7-1 based on comparison of 165 rDNA sequences revealed that this strain is closely related to Bacillus megaterium.