• 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.

• Journal of Microbiology and Biotechnology
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• v.21 no.2
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• pp.129-135
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• 2011

Cloning and characterization of the gene encoding a solvent-tolerant protease from the haloalkaliphilic bacterium Geomicrobium sp. EMB2 are described. Primers designed based on the N-terminal amino acid sequence of the purified EMB2 protease helped in the amplification of a 1,505-bp open reading frame that had a coding potential of a 42.7-kDa polypeptide. The deduced EMB2 protein contained a 35.4-kDa mature protein of 311 residues, with a high proportion of acidic amino acid residues. Phylogenetic analysis placed the EMB2 gene close to a known serine protease from Bacillus clausii KSM-K16. Primary sequence analysis indicated a hydrophobic inclination of the protein; and the 3D structure modeling elucidated a relatively higher percentage of small (glycine, alanine, and valine) and borderline (serine and threonine) hydrophobic residues on its surface. The structure analysis also highlighted enrichment of acidic residues at the cost of basic residues. The study indicated that solvent and salt stabilities in Geomicrobium sp. protease may be accorded to different structural features; that is, the presence of a number of small hydrophobic amino acid residues on the surface and a higher content of acidic amino acid residues, respectively.

• 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.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.187-193
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• 2012

Serine proteases are major insect enzymes involved in the digestion of dietary proteins and in the process of blood meal digestion. In this study, cDNA was constructed using the whole body of Laccotrephes japonensis. The flanking sequences of the 5- and 3- end of this gene were characterized by RACE-PCR. Sequence analysis showed that this gene contained a 963-bp ORF encoding 320 amino acids. The deduced amino acid sequence showed 62% identity with the Creontiades dilutus serine protease, 58% with the Lygus lineolaris trypsin precursor, and 54% with the Triatoma infestans salivary trypsin. To assess the expression of the L. japonensis serine protease (JGsp), the JGsp gene was cloned into a baculovirus transfer vector, pBac-1, and expressed in Sf9 cells (Spodoptera frugiperda). SDS-PAGE and western blot analysis have shown that the JGsp recombinant protein was a monomer with a molecular weight of about 32 kDa. Recombinant JGsp has shown activity in the protease enzyme assay using gelatin as a substrate.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.448-453
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• 2018

In this study, a 107 kDa protease from psychrophilic Janthinobacterium lividum PAMC 26541 was purified by anion-exchange chromatography. The specific activity of the purified protease was 264 U/mg, and the overall yield was 12.5%. The J. lividum PAMC 25641 protease showed optimal activity at pH 7.0-7.5 and $40^{\circ}C$. Protease activity was inhibited by PMSF, but not by DTT. On the basis of the N-terminal sequence of the purified protease, the gene encoding the cold-adapted protease from J. lividum PAMC 25641 was cloned into the pET-28a(+) vector and heterologously expressed in Escherichia coli BL21(DE3) as an intracellular soluble protein.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.852-858
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• 2008

An extracellular protease (Mc1) was isolated from the nematode-trapping fungus Monacrosporium cystosporium by gel filtration, anion-exchange, and hydrophobic interaction chromatographies. This protease had a molecular mass of approximately 38 kDa and displayed an optimal activity at pH 7-9 and $56^{\circ}C$ (over 30 min). Its proteolytic activity was highly sensitive to the serine protease inhibitor PMSF (phenylmethylsulfonylfluoride, 0.1 mM), indicating that it belonged to the serine-type peptidase group. The Michaelis constant ($K_m$) and $V_max$ for substrate N-Suc-Ala-Ala-Pro-Phe-pNA were $1.67{\times}10^{-4}\;M$ and 0.6071 $OD_{410}$ per 30 s, respectively. This protease could degrade a broad range of substrates including casein, gelatin, BSA (bovine serum albumin), and nematode cuticle. Moreover, the enzyme could immobilize the free-living nematode Panagrellus redivivus and the pine wood nematode Bursaphelenchus xylophilus, suggesting that it might playa role in infection against nematodes. The encoding gene of Mc1 was composed of one intron and two exons, coding for a polypeptide of 405 amino acid residues. The deduced amino acid sequence of Mcl showed 61.4-91.9% identity to serine proteases from other nematode-trapping fungi. Our results identified that Mcl possessed biochemical properties including optimal reaction condition and substrate preference that are different from previously identified serine proteases.

• Microbiology and Biotechnology Letters
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• v.20 no.3
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• pp.280-288
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• 1992

Molecular cloning of metalloprotease gene from Serratia marcescens ATCC 21074 into Escherichia coli JM109 was carried out. Chromosomal DNA of S. marcescens was completely digested with Hind111 and southern hybridization with a synthetic oligonucleotide probe revealed that a 50 KD metalloprotease gene was contained in 4.0 Kb chromosomal DNA fragment, 4.0 Kb chromosomal DNA fragments eluted from agarose gel were ligated with pUC19 and transformed into E. coli JM109. Nine positive clones were obtained from about $1\times 10^3$ transformants by colony hybridization. Their recombinant plasmids, pSPl and pSP2 have same chromosomal DNA fragments in pUC19 in opposite-orientations. When cloned metalloprotease gene was expressed in E. coli, about 52 KD precursor protein of metalloprotease was detected by western blot analysis from E. coli harboring a recombinant plasmid pSP2. Plasmid pSP2 showed no protease activities in E. coli but overproduced the active metalloprotease in S. rnarcescens ATCC 27117.

• Food Science and Preservation
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• v.7 no.4
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• pp.414-417
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• 2000

Competent cell transformation of B. subtilis AC819 was carried out using phenotypic protease-defective(Npr-) DNA of B. subtilis MT-2. An obtained transformant, designated B. subtilis HL-1, was obtained by homologous DNA recombination. Phenotypes of B. subtilis HL-1 were characterized histidine requirement streptomycin-resistance, tetracyclin resistance and non-producing protease. Protoplast transformation frequency of B. subtilis HL-1 by plasmid pUB110 was higher than that of B. subtilis MT-2. From this result, B. subtilis HL-1 is useful for protease gene transformation and thermostable protease gene cloning as a host.

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.201.1-201
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• 2003

No Abstract, See Full Text

• Proceedings of the Korean Society of Life Science Conference
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• 2003.10a
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• pp.72-72
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• 2003