• Parasites, Hosts and Diseases
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• v.54 no.6
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• pp.759-768
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• 2016

Cystic echinococcosis (CE) treatment urgently requires a novel drug. The p38 mitogen-activated protein kinases (MAPKs) are a family of Ser/Thr protein kinases, but still have to be characterized in Echinococcus granulosus. We identified a 1,107 bp cDNA encoding a 368 amino acid MAPK protein (Egp38) in E. granulosus. Egp38 exhibits 2 distinguishing features of p38-like kinases: a highly conserved T-X-Y motif and an activation loop segment. Structural homology modeling indicated a conserved structure among Egp38, EmMPK2, and H. sapiens $p38{\alpha}$, implying a common binding mechanism for the ligand domain and downstream signal transduction processing similar to that described for $p38{\alpha}$. Egp38 and its phosphorylated form are expressed in the E. granulosus larval stages vesicle and protoscolices during intermediate host infection of an intermediate host. Treatment of in vitro cultivated protoscolices with the p38-MAPK inhibitor ML3403 effectively suppressed Egp38 activity and led to significant protoscolices death within 5 days. Treatment of in vitro-cultivated protoscolices with $TGF-{\beta}1$ effectively induced Egp38 phosphorylation. In summary, the MAPK, Egp38, was identified in E. granulosus, as an anti-CE drug target and participates in the interplay between the host and E. granulosus via human $TGF-{\beta}1$.

• Journal of Life Science
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• v.20 no.9
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• pp.1306-1313
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• 2010

The gene encoding esterase enzyme was cloned from a metagenomic library of cow rumen bacteria. The esterase gene (est1R) was 2,465 bp in length, encoding a protein of 366 amino acid residues, and the molecular weight of the enzyme was 61,166 Da. Est1R of rumen cosmid library shared 5.9% amino acid identity with Est1R (P37967) of PNB carboxylesterase, 6.1% with Est1R (1EEAA) of acetylcholinesterase and 6.1% with Est1R (1H23A) of chain A. BlastP in NCBI database analysis of Est1R revealed that it was not homologous to previous known lipases and esterases. Est1R showed optimum activity at pH 7.0 and $40^{\circ}C$. On the other hand, the enzyme was found to be most active without organic solvent, followed by 95% activity with methanol, and the enzyme activity was highly affected by hexane (lost 51% activity). Therefore, the novel esterase gene est1R is likely obtainable from cow rumen metagenome and may be utilized for industrial purposes.

• Journal of Life Science
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• v.28 no.4
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• pp.478-482
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• 2018

Human rotavirus is a causative agent of acute diarrhea among children. The artificial gene encoding the truncated $VP8^*$ protein of human rotavirus A (serotype 1 strain WA) was synthesized according to the Escherichia coli codon preference. The synthetic $VP8^*$ gene also possessed the NdeI and HindIII restriction sites for the convenient in-frame cloning for translation and a 6-histidine tag at C-terminus for Ni+ affinity purification. Molecular weight of the truncated $VP8^*$ protein deduced from the nucleotide sequences of the artificial gene was a 19.7-kDa. This synthetic $VP8^*$ DNA fragment was inserted into the pT7-7 expression vector and transformed into E. coli BL21 (DE3). Transformants harboring the synthetic gene encoding the $VP8^*$ protein was induced by supplement of a final concentration of 0.05 mM ITPG at $20^{\circ}C$. Protein crude extract from the E. coli transformants was subjected to Western blotting with the mouse anti-rotavirus capsid antibody, showing ~20-kDa $VP8^*$ protein band. The truncated $VP8^*$ protein band was also observed by Western blotting using the rabbit polyclonal antibody serum made against the truncated $VP8^*$ protein. This study suggested that the synthetic gene could be used as an easy way to produce the antigenic vaccine candidate for control of virus-associated diseases or to develop antibodies for diagnostic purpose.

• The Journal of Korean Society of Virology
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• v.26 no.1
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• pp.121-129
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• 1996

Multiplication of Herpes simplex virus type-1 was observed by electronmicroscopy, a gene library of the genome was constructed and thymidine kinase gene was cloned. Vero cells infected with the virus were lysed 48 h p.j. and multinucleated giant cells were observed approximately at 72 h p.i. The nucleocapsids were observed in nuclei and cytoplasm, and the assembled nucleocapsids were budded out through the vacuole and cytoplasmic membranes, and then virions were released from the cells. HSV-1 genome DNA was digested with BamHI and BglII enzymes and then the gene library of the genome fragments were constructed. The BamHI cleaved the genome DNA into twenty-seven fragments in the range of 1.1 - 14 kb, and BglII cleaved the genome DNA into sixteen fragments in the range of $4.5{\sim}20.1\;kb$. The pHLA-12 and pHLB-4 recombinant plasmids were contained TK gene by Southern blot analysis. The molecular sizes of the fragments which contained the TK gene were 3.74 in pHLA-12 and 6.41kb in pHLB-4 recombinant plasmid, respectively.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.69-75
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• 2002

Sterols play two major roles in plants: a bulk component in biological membranes and precursors of plant steroid hormones. Physiological effects of plant steroids, brassinosteroids (BRs), include cell elongation, cell division, stress tolerance, and senescence acceleration. Arabidopsis mutants that carry genetic defects in BR biosynthesis or its signaling display characteristic phenotypes, such as short robust inflorescences, dark-green round leaves, and sterility. Currently there are more than 100 dwarf mutants representing 7 genetic loci in Arabidopsis. Mutants of 6 loci, dwf1/dim1/cbb1, cpd/dwf3, dwf4, dwf5, det2/dwf6, dwf7 are rescued by exogenous application of BRs, whereas bri1/dwf2 shares phenotypes with the above 6 loci but are resistant to BRs. These suggest that the 6 loci are defective in BR biosynthesis, and the one locus is in BR signaling. Biochemical analyses, such as intermediate feeding tests, examining the levels of endogenous BR, and molecular cloning of the genes revealed that dwf7, dwf5, and dwf1 are defective in the three consecutive steps of sterol biosynthesis, from episterol to campesterol via 5-dehydroepisterol. Similarly, det2/dwf6, dwf4, and cpd/dwf3 were Shown to be blocked in $D^4$ reduction, 22a-hydroxylation, and 23 a-hydroxylation, respectively. A signaling mutant bri1/dwf2 carries mutations in a Leucine-rich repeat receptor kinase. Interestingly, the bri1 mutant was shown to accumulate significant amount of BRs, suggesting that signaling and biosynthesis are dynamically coupled in Arabidopsis. Thus it is likely that transgenic plants over-expressing the rate-limiting step enzyme DWF4 as well as blocking its use by BRI1 could dramatically increase the biosynthetic yield of BRs. When applied industrially, BRs will boost new sector of plant biotechnology because of its potential use as a precursor of human steroid hormones, a novel lead compound for cholesterol-lowering effects, and a various application in plant protection.

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.104-111
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• 2002

The peptidyl prolyl sis-trans isomerase (PPIase, EC 5.2.1.8) from bacillus stearothermophilus was extracted from the cells treated with by lysozyme. PPIase was purified from the cell extracts by heat treatment, ammonium sulfate precipitation, ion exchange chromatography and finally gel filtration, sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE). The molecular weight of the purified PPIase was estimated as 18kDa by SDS-PAGE. The 39 amino acid residues from the N-terminus were determined by the protein sequencer. The enzyme showed the optimum pH at 8.0 and was stable at the range of pH 7.0∼8.0. The enzyme was considerably stable after heat treatment at 60$\^{C}$ for 30minutes, and the enzyme was quite stable up to 65$\^{C}$. The presence of the PPIase in the refolding solution accelerated the isomerization rate of the assay peptide. PPIase gene of Bacillus stearothermophilus was screened from a genomic library by plaque hybridization using the A-l primer as a probe. A PPIase positive plaque contained a 3.0kb insert of the chromosomal DNA. A 3.0kb fragment was subcloned into pUC18, resulting pPI-40. A DNA fragment encoding the N-terminal portion of the PPIase in pPI-40 was amplified by polymerase chain reaction(PCR) method using the A-1 and B-2 primers. The amplified fragment was cloned into the Sma I site of pUC18 and recombinant plasmid was designated as pSN-18. The nucleotide sequence of 167bp fragment was determined. The deduced amino acid sequence of PPIase was completely matched with the determined N-terminal amino acid sequence of PPIase B. stearothermophilus.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.5
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• pp.736-742
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• 2017

Objective: Experiments were conducted to clone the sequence of Wild Argali short palate, lung and nasal epithelium clone 1 (SPLUNC1) cDNA, and to lay the foundation for further study the biological function of Wild Argali SPLUNC1. Methods: The complete sequence of Wild Argali SPLUNC1 cDNA was generated by rapid amplification of cDNA ends. The entire coding sequence was inserted into the pPIC9K vector and expressed in Pichia pastoris (P. pastoris) GS115. The recombinant SPLUNC1 protein was detected by Western blot and purified by $Ni^{2+}$ chelate affinity chromatography. The test of effect of the protein on Mycoplasma ovipneumoniae (MO) was performed with real-time polymerase chain reaction. Results: The Wild Argali SPLUNC1 cDNA was 1,076 bp with an open reading frame of 768 bp, which encoded a 26.49 kDa protein composed of 255 amino acids. Its amino acid sequence shared 98.4%, 96.9%, 94.5%, 90.2%, 80.8%, 78.4%, 78.3%, 72.5%, 72.3%, 68.8% identity with those of SPLUNC1 cDNA from Ovis aries (accession no. NP_001288334.1), Capra hircus (accession no. XP_005688516.1), Pantholops hodgsonii (accession no. XP_005979709.1), Bos taurus (accession no. NP_776851.1), Felis catus (accession no. XP_006929910.1), Homo sapiens (accession no. NP_001230122.1), Sus scrofa (accession no. NP_001005727.1), Chinchilla lanigera (accession no. NP_001269294.1), Mus musculus (accession no. NP_035256.2), and Rattus norvegicus (accession no. NP_742028.1), respectively. The recombinant protein corresponded to the expected molecular mass of 25.47 kDa as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and it was detected in the supernatant of P. pastoris, and it could be purified. The results from the test of inhibition effect of argali recombinant SPLUNC1 protein on MO showed that the product could inhibit MO very well (p<0.01). Conclusion: The amino acid sequence of Wild Argali SPLUNC1 was different from other organisms. The recombinant SPLUNC1 protein has good biological activity.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.607-615
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• 2018

Objective: This study was conducted to isolate the cellulolytic microorganism from the rumen of Holstein steers and characterize endoglucanase gene (Cel5A) from the isolated microorganism. Methods: To isolate anaerobic microbes having endoglucanase, rumen fluid was obtained from Holstein steers fed roughage diet. The isolated anaerobic bacteria had 98% similarity with Eubacterium cellulosolvens (E. cellulosolvens) Ce2 (Accession number: AB163733). The Cel5A from isolated E. cellulolsovens sp. was cloned using the published genome sequence and expressed through the Escherichia coli BL21. Results: The maximum activity of recombinant Cel5A (rCel5A) was observed at $50^{\circ}C$ and pH 4.0. The enzyme was constant at the temperature range of $20^{\circ}C$ to $40^{\circ}C$ but also, at the pH range of 3 to 9. The metal ions including $Ca^{2+}$, $K^+$, $Ni^{2+}$,$Mg^{2+}$, and $Fe^{2+}$ increased the endoglucanase activity but the addition of $Mn^{2+}$, $Cu^{2+}$, and $Zn^{2+}$ decreased. The Km and Vmax value of rCel5A were 14.05 mg/mL and $45.66{\mu}mol/min/mg$. Turnover number, Kcat and catalytic efficiency, Kcat/Km values of rCel5A was $96.69(s^{-1})$ and 6.88 (mL/mg/s), respectively. Conclusion: Our results indicated that rCel5A of E. cellulosolvens isolated from Holstein steers had a broad pH range with high stability under various conditions, which might be one of the beneficial characteristics of this enzyme for possible industrial application.

• Biomedical Science Letters
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• v.9 no.3
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• pp.139-144
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• 2003

Since water borne infection causes acute diseases and results in spread of diseases by secondary infection, the prevention is very important. Therefore, it is necessary to have a method that is rapid and effective to monitor pathogenic bacteria in drinking water. In this study, we employed a systematic method, Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) analysis, to develop an effective monitoring system for possible bacterial contaminants in drinking water. For this purpose, PCR primers were derived from 992 bp region of the 16s rRNA gene that is highly conserved through the different species of prokaryotes. To test whether the PCR primers designed are indeed useful for detecting all the possible microbial contaminants in the water, the primers were used to amplify 16s rRNA regions of different microbial water-borne pathogens such as E. coli, Salmonella, Yersinia, Listeria, and Staphylococcus. As expected, all of tested microorganisms amplified expected size of PCR products indicating designed PCR primers for 16s rRNA indeed can be useful to amplify all different microbial water-borne pathogens in the water. Furthermore, to test whether these 16s rRNA based PCR primers can detect bacterial populations present in the water, water samples taken from diverse sources, such as river, tap, and sewage, were used for amplification. PCR products were for then subjected for cloning into a T-vector to generate a library containing 16s rRNA sequences from various bacteria. With cloned PCR products, RFLP analysis was done using PCR products digested with restriction enzyme such as Hae III to obtain species-specific RFLP profiles. After PCR-RFLP, the bacterial clones which showed the same RFLP profiles were regarded as the same ones, and the clones which showed distinctive RFLP profiles were subsequently subjected for sequence analysis for species identification. By this PCR-RFLP analysis, we were able to reveal diverse populations of bacteria living in water. In brief, in unsterilized natural river water, over 60 different species of bacteria were found. On the other hand, no PCR products were detected in drinking tap-water. The results from this study clearly indicate that the PCR-RFLP-sequence analysis can be a useful method for monitoring diverse, perhaps pathogenic bacteria contaminated in water in a rapid fashion.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1460-1468
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• 2007

In this study, an approx. 2.5-kb gene fragment including the catalase gene from Rhodospirillum rubrum S1 was cloned and characterized. The determination of the complete nucleotide sequence revealed that the cloned DNA fragment was organized into three open reading frames, designated as ORF1, catalase, and ORF3 in that order. The catalase gene consisted of 1,455 nucleotides and 484 amino acids, including the initiation and stop codons, and was located 326 bp upstream in the opposite direction of ORF1. The catalase was overproduced in Escherichia coli UM255, a catalase-deficient mutant, and then purified for the biochemical characterization of the enzyme. The purified catalase had an estimated molecular mass of 189 kDa, consisting of four identical subunits of 61 kDa. The enzyme exhibited activity over a broad pH range from pH 5.0 to pH 11.0 and temperature range from $20^{\circ}C$ to $60^{\circ}C$C. The catalase activity was inhibited by 3-amino-1,2,4-triazole, cyanide, azide, and hydroxylamine. The enzyme's $K_m$ value and $V_{max}$ of the catalase for $H_2O_2$ were 21.8 mM and 39,960 U/mg, respectively. Spectrophotometric analysis revealed that the ratio of $A_{406}$ to $A_{280}$ for the catalase was 0.97, indicating the presence of a ferric component. The absorption spectrum of catalase-4 exhibited a Soret band at 406 nm, which is typical of a heme-containing catalase. Treatment of the enzyme with dithionite did not alter the spectral shape and revealed no peroxidase activity. The combined results of the gene sequence and biochemical characterization proved that the catalase cloned from strain S1 in this study was a typical monofunctional catalase, which differed from the other types of catalases found in strain S1.