• Microbiology and Biotechnology Letters
• /
• v.42 no.4
• /
• pp.339-346
• /
• 2014

A bacterial strain was isolated from homemade doenjang (Korean fermented soybean paste) as a producer of the extracellular ${\beta}$-galactosidase, capable of hydrolyzing lactose to liberate galactose and glucose residues. The isolate YB-1414 has been identified as Bacillus licheniformis on the basis of its 16S rDNA sequence, morphology and biochemical properties. The production of ${\beta}$-galactosidase by B. licheniformis YB-1414 reached maximum levels of 6.2 U/ml in culture medium containing wheat bran (1%) and yeast extract (2.5%) as carbon and nitrogen sources, respectively. Particularly, the insoluble fraction was more effective for ${\beta}$-galactosidase production than the soluble extract of wheat bran. The enzyme exhibited maximum activity for hydrolysis of para-nitrophenyl-${\beta}$-D-galactopyranoside (pNP-${\beta}Gal$) under reaction conditions of pH 6.0 and $55-60^{\circ}C$. Its hydrolyzing activity for pNP-${\beta}Gal$ was drastically decreased by the addition of low concentrations of galactose, but only slightly decreased by glucose, with 85% of maximal activity in the presence of 400 mM glucose.

• Microbiology and Biotechnology Letters
• /
• v.40 no.1
• /
• pp.17-22
• /
• 2012

A bacterial strain was isolated from homemade Cheongkookjang as a producer of the ${\beta}$-galactosidase, capable of hydrolyzing lactose to liberate galactose and glucose residues. The isolate YB-1105 has been identified as Bacillus licheniformis on the basis of its 16S rDNA sequence, morphology and biochemical properties. ${\beta}$-Galactosidase activity was detected in both the culture supernatant and the cell extract of B. licheniformis YB-1105. The enzymes of both fractions demonstrated maximum activity for hydrolysis of para-nitrophenyl-${\beta}$-D-galactopyranoside (pNP-${\beta}Gal$) under identical reaction conditions of pH 6.5 and $50^{\circ}C$. However, ${\beta}$-galactosidase activity from the culture filtrate was affected more than that from the cell free extract at acidic pHs and high temperatures. The hydrolyzing activity of both ${\beta}$-galactosidases for pNP-${\beta}Gal$ was dramatically decreased by the addition of low concentrations of galactose, but was only marginally decreased by high concentrations of glucose or mannose.

• Korean Journal of Veterinary Service
• /
• v.40 no.1
• /
• pp.53-59
• /
• 2017

Foot and mouth disease (FMD) is highly infectious disease of cloven-hoofed animals, particularly problematic in cattle, sheep, pigs and goats for economic reasons. Last FMD outbreak in February, 2017 caused tremendous social and economical impacts. The Korean FMD policy aims to vaccinate intact animals and euthanize and bury infected animals to prevent the disease spread. However, there was a problem that the buried livestock did not decompose after several years. Therefore, the study was purposed to investigate the effect of Corynebacterium glutamicum and Bacillus licheniformis on the degradation of buried cow carcasses and on the soil condition; such as temperature, decomposition course of carcasses, composition of amino acids in the soil around carcasses, and plant root elongation to measure soil conditions. As a result, the composition of amino acids in the soil treated with C. glutamicum and B. licheniformis was generally higher than those in the untreated soil. Plant roots in soil treated with C. glutamicum and B. licheniformis grew longer than in non-treated soil. The results suggested that the toxic effect on a grave land buried with FMD infected livestock is reduced when treated with C. glutamicum and B. licheniformis in regard of odor reduction, promoted decaying process, and soil fertilization.

• Journal of Life Science
• /
• v.17 no.7 s.87
• /
• pp.983-989
• /
• 2007

Bacillus lichemiformis Kll, a plant growth promoting rhizobacterium was reported as a producer of auxin, siderophore, as well as antifungal cellulase under some culture conditions. In vitro test, B. licheniformis Kll represented excellent antagonistic ability against Fusarium oxyspoum (KACC 40037), and showed broad spectrum against other phytopathogenic fungi. B. licheniformis Kll had cellulolytic activity toward not only carboxymethyl-cellulose (CMC) but also insoluble cellulose, such as fungal cell wall cellulose, filter paper (Whatman No. 1), and Avicel. In addition, we confirmed antifungal substance production by butanol-extract methods. The strain produced optimally the antifungal substance when it was cultivated at pH 9.0, 30${\circ}$C for 4 days on nutrient medium. The biological control mechanisms of B. lichemiformis Kll were caused by antifungal substance, cellulase and siderophore against phytopathogenic fungi.

• KSBB Journal
• /
• v.25 no.6
• /
• pp.539-546
• /
• 2010

In this work, mass production of Bacillus licheniformis SCD121067 through medium optimization by statistical experimental method was studied. First, galactose, yeast extract and potassium phosphate dibasic were selected as carbon, nitrogen and phosphate sources for mass production of B. licheniformis SCD121067 by using one factor at a time method. Second, according to the result of Plackett-Burman experimental design, key factors was yeast extract and $K_2HPO$. Finally, the response surface methodology was performed to obtain the optimum concentrations of two selected variables. The optimized medium composition consisted of 20 g/L galactose, 36 g/L yeast extract, 0.41 g/L $K_2HPO4$, 0.25 g/L $Na_2CO_3$, 0.4g/L $MgSO_4$ and 0.01g/L $CaCl_2$. Dry cell weight (15.4 g/L) by optimum production medium were increased 10 times, as compared to that determined with basic production medium (1.5 g/L). Fermentation conditions were examined for the mass production of B. licheniformis. The effect of temperature, agitation speed, pH and aeration rate on the mass production of B. licheniformis were also studied in a batch fermenter which was carried out in a 2.5 L bioreactor with a working volume of 1.5 L containing optimized production medium. As a result, dry cell weight of batch culture was 30.7 g/L at $42^{\circ}C$, 300 rpm, pH 8.0 and 2 vvm.

• Journal of Food Hygiene and Safety
• /
• v.29 no.1
• /
• pp.40-46
• /
• 2014

We have screened Bacillus strains suitable for the fermentation of soybean products with respect to the control of Bacillus cereus and the reduction of biogenic amines. Of 26 isolates, a strain named as the SCK A08 carried antimicrobial activity against B. cereus and Staphylococcus aureus, major food poisoning species in soybean products. PCR analysis revealed that the SCK A08 strain did not contain genes for Bacillus cereus toxins including nonhemolytic enterotoxin, hemolytic enterotoxin, cytotoxin K, cereulide and certrax. The SCK A08 strain could degrade histamine, tyramine, putrescine, and cadaverine by 67.41%, 76.59%, 57.32%, and 50.69%, respectively, during fermentation in cooked soybeans containing 0.5% (w/w) of each biogenic amine. The morphological and biochemical properties and phylogenetic relationships based on 16S rRNA gene sequences indicated that the isolate was most closely related to Bacillus licheniformis. Use of the strain SCK A08 would be a potential measure to overcome two hygienic problems that were frequently faced during manufacture of traditionally fermented soybean products.

• Korean Journal of Environmental Agriculture
• /
• v.22 no.3
• /
• pp.203-209
• /
• 2003

In the course of screening for antifungal agents, a bacterial strain, DM3 was isolated from a mud sample collected at Daechon in Chungnam province and identified as Bacillus licheniformis based on API 50CHB test. It has antifungal activity against 12 plant pathogenic fungi in paper disc assay. At the 95% lethal dose of gamma radiation ($^{60}Co$, 10 kGy, $D_{10}=2.32\;kGy$), the antifungal activity deficient mutant (mDM3) against Colletotrichum gloeosporioides was induced From 2-D electrophoresis analysis, serine hydroxymethyltransferase (45.0 kDa), hypothetical protein(40.7 kDa), NifU protein homolog(15.4 kDa), and resolvase(12.5 kDa) homologous proteins were detected only in B. licheniformis DM3. Lysozyme(18.1 kDa) and alkyl hydroperoxide reductase(15.6 kDa) homologous proteins were expressed uniquely in B. licheniformis mDM3. Further studies are needed to reveal that these proteins from B. licheniformis DM3 could be closely related to the antifungal activity against plant pathogenic fungi.

• Applied Biological Chemistry
• /
• v.50 no.1
• /
• pp.23-28
• /
• 2007

Auxin-producing antagonistic bacterium K11, which can inhibit Phytophtora capsici, was isolated from a local red-pepper field soil in Gyeong-buk. In order to check for additional PGPR(plant growth promoting rhizobacterium) functions of the strain K11, we confirmed siderophore and cellulase productions by CAS (chrome azurol S) blue agar and CMC plate with congo red, respectively. The strain K11 was identified as Bacillus licheniformis with 98% similarity on 16s rDNA comparison and Biolog analyses. B. licheniformis K11 promoted mung bean adventitious root induction and enhanced root growth of mung bean (160%), pea (150%), and Chinese cabbage (130%), Also, B. licheniformis K11 was able to effectively suppress (63%) P. capsici causing red-pepper blight in the pot in vivo test. Therefore, we could select a triple-functional PGPR which has auxin, siderophore, and cellulase producing ability for effective crops production in organic farming.

• Korean Journal of Microbiology
• /
• v.48 no.2
• /
• pp.163-170
• /
• 2012

In order to inhibit the growth of pathogens and degrade biogenic amines during the fermentation of soybean products, an isolate with antimicrobial activity against pathogens and biogenic amine-degrading property was obtained from 83 traditionally fermented soybean products. The morphological and biochemical tests and the phylogenetic relationship among 16S rRNA gene sequences indicated that the isolate named as the strain SCK B11 was most closely related to Bacillus licheniformis. The cell-free supernatant of two day cultures was active against several pathogens including Enterococcus faecalis, Listeria monocytosis, Micrococcus luteus, Pseudomonas aeruginosa, Bacillus cereus, and Staphylococcus aureus. PCR analysis was conducted to determine relatedness to antimicrobial lantibiotics and biosurfactants produced by Bacillus spp., but showed negative for the genes encoding surfactin, lichenysin, and lichenicidine. Electron microscopic observation indicated that the antimicrobial agent seemed to attack the membrane of the pathogens, leaving the ghost or shrunken cells. The strain was found to degrade histamine by 72% and tyramine by 66% in the cooked soybean containing 5.3% of biogenic amine over 10 days of fermentation time. The use of selected strain would be a potential control measure in manufacturing traditionally fermented soybean products that are difficult to control pathogens and biogenic amine levels.

• Microbiology and Biotechnology Letters
• /
• v.48 no.2
• /
• pp.185-192
• /
• 2020

The global carbon storage regulator (Csr) system is conserved in bacteria and functions as a regulator in the exponential and stationary phases of growth in batch culture. The Csr system plays a role in the central carbon metabolism, virulence, motility, resistance to oxidative stress, and biofilm formation. Although the Csr was extensively studied in Gram negative bacteria, it has been reported only in the control of motility in Bacillus subtilis among Gram positive bacteria. The goal of this study was to explore the role of the csrA gene of Bacillus licheniformis M2-7 on motility and the bacterial ability to use hydrocarbons as carbon source. We deleted the csrA gene of B. licheniformis M2-7 using the plasmid pCsr-L, harboring the spectinomycin cassette obtained from the plasmid pHP45-omega2. Mutants were grown on culture medium supplemented with 2% glucose or 0.1% gasoline and motility was assessed by electron microscopy. We observed that CsrA negatively regulates motility by controlling the expression of the hag gene and the synthesis of flagellin. Notably, we showed the ability of B. licheniformis to use gasoline as a unique carbon source. Our results demonstrated that CsrA is an indispensable regulator for the growth of B. licheniformis M2-7 on gasoline.