• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.558-563
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• 2001

A new alkalophilic strain of Bacillus pumilus JB¬05 producing bleach-stable and halo-tolerant alkaline protease was isolated from cement industry effluents in Karnataka, India. The effects of carbon and nitrogen sources on protease production by this alkalophilic strain were observed after a 30-h incubation. A high level of alkaline protease activity was obtained in the presence of starch as the carbon and peptone as the nitrogen sources. The partially purified enzyme showed an optimum temperature and pH activity at $58^{\circ}C$ and 10.5, respectively. The enzyme was completely inhibited by PMSF (95.0%) indicating it as a serine protease. It is bleach-stable as it retained 35% original activity in the presence of 10% (v/v) hydrogen peroxide at $30^{\circ}$C after 2 h and is halo-tolerant as it retained 70% original activity in the presence of 2.5 M sodium chloride at $30^{\circ}C$ after 2 h incubation.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.197-208
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• 2014

A novel protease gene from Bacillus gibsonii, aprBG, was cloned, expressed in B. subtilis, and characterized. High-level expression of aprBG was achieved in the recombinant strain when a junction was present between the promoter and the target gene. The purified recombinant enzyme exhibited similar N-terminal sequences and catalytic properties to the native enzyme, including high affinity and hydrolytic efficiency toward various substrates and a superior performance when exposed to various metal ions, surfactants, oxidants, and commercial detergents. AprBG was remarkably stable in 50% organic solvents and retained 100% activity and stability in 0-4 M NaCl, which is better than the characteristics of previously reported proteases. AprBG was most closely related to the high-alkaline proteases of the subtilisin family with a 57-68% identity. The secretion and maturation mechanism of AprBG was dependent on the enzyme activity, as analyzed by site-directed mutagenesis. Thus, when taken together, the results revealed that the halo-solvent-tolerant protease AprBG displays significant activity and stability under various extreme conditions, indicating its potential for use in many biotechnology applications.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.63-68
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• 1986

In order to examine related bacteria on the maturation of cured loin ham, bacteria isolated during curing periods from ham, which counted coliform group, psychrotrophic and halo-tolerant bacteria. The results are as follows; The isolated bacteria from ham during the curing period were Staphylococcus spp. 24 strains, Bacillus spp. 21 strains, Lactobacillus spp. 10 strains, Coryneform 2 strains. Microbacterium spp. 2 strains and Gram negative rods 8 strains. Micrococcus spp. were identified M. varians 12 strains and M. luteus 3 strains, and Streptococcus spp. identified S. faecium 14 strains, S. lactis 2 strains. Lactobacillus spp. were isolated L. Plantarum 4 strains, L. brevis and L. casei 1 strains. In the case of cured ham, the number of coliform group and psychrotrophic bacteria were decreased but halo-tolerant bacteria were increased for 10 days of curing period. On the brine solution. the number of coliform group, psychrotrophic and halo-tolerant bacteria were increased for 10 days. 4 days and 20 days, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.69-74
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• 1986

In order to examine the effect of 'Lactobacillus plantarum' inoculation on the maturation of cured loin ham, bacteriological and biochemical changes in meat were investigated during curing periods. The results were summarized as follow; On the bacteriological changes of cured ham, during curing periods, the number of coliform group were decreased. while psychrotrophic and halo-tolerant bacteria were increased until the 4 days. In the brine solution after the 7days of the curing, the number of coliform group were decreased the 7 days, but psychrotophic and halo-tolerant bacteria were increased until the 7 days of curing. The pH value of the meat and curing solution were sharply decreased at the one day, since these were slightly increased from 4 days. The color development of cured meat was showed 84.05 % development of within the 7 days of curing. Glutamic acid contents among the 17 kinds of amino acid were the highest at the 7 and 10 days of curing. The 13 kinds of fatty acids detected from at the all sample and total contents of unsaturated fatty acid were slightly decreased during curing.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.201-212
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• 2011

The alkaline protease gene was cloned from a halo-tolerant alkalophilic Bacillus clausii I-52 isolated from the heavily polluted tidal mud flat of West Sea in Inchon Korea, which produced a strong extracellular alkaline protease (BCAP). Based on the full genome sequence of Bacillus subtilis, PCR primers were designed to allow for the amplification and cloning of the intact pro-BCAP gene including promoter region. The full-length gene consists of 1,143 bp and encodes 381 amino acids, which includes 29 residues of a putative signal peptide and an additional 77-amino-acid propeptide at its N-terminus. The mature BCAP deduced from the nucleotide sequence consists of 275 amino acids with a N-terminal amino acid of Ala, and a relative molecular weight and pI value was 27698.7 Da and 6.3, respectively. The amino acid sequence shares the highest similarity (99%) to the nattokinase precursor from B. subtilis and subtilisin E precursor from B. subtilis BSn5. The substrate specificity indicated that the recombinant BCAP could hydrolyze efficiently the synthetic substrate, N-Suc-Ala-Ala-Pro-Phe-pNA,and did not hydrolyze the substrates with basic amino acids at the P1 site. The recombinant BCAP was strongly inhibited by typical serine protease inhibitor, PMSF, indicating that BCAP is a member of the serine proteases.