• BMB Reports
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• v.31 no.3
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• pp.303-306
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• 1998

Serine proteinase cDNA fragment from protozoan parasite Acanthamoeba culbertsoni was amplified by the reverse transcription-polymerase chain reaction (RTPCR) using degenerate oligonucleotide primers derived from conserved serine proteinase sequences. The amplified DNA fragment was subcloned and sequenced. The sequence analysis and alignment showed significant sequence similarity to other eukaryotic serine proteinases and conservation of the His, Asp, and Ser residues that form the catalytic triad. The cDNA fragment was cloned into the pGEMEX-1 expression vector and expressed in Escherichia coli. A resulting fusion protein of 56 kDa had proteolytic activity. The fusion protein reacted with sera of mice immunized with purified serine proteinase of A. culbertsoni in Western blot. Immune recognition of the fusion protein by mouse antisera suggested that the fusion protein may be valuable as a diagnostic reagent.

• Journal of Microbiology and Biotechnology
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• v.5 no.2
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• pp.87-91
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• 1995

The chitinase gene was cloned from Acinetobacter sp. WC-17 for investigating the genetic control and enzymatic properties of bacterial chitinase. A genomic library of Acinetobacter sp. WC-17 was prepared in E.coli JM109 by using pUC18 as a vector. The chitinase-positive clone containing 3.2kb insert fragment was obtained from 5, 000 insert-bearing transformants. The optimum pH and temperature of cloned enzyme were 6.0 and $55^{\circ}C$, respectively. Almost all the chitinase activity of E.coli recombinant was localized in the periplasmic fraction, while most of the enzyme activity of Acinetobacter sp. WC-17 was found in the extracellular fraction.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1294-1298
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• 2011

A metK gene encoding S-adenosyl-L-methionine synthetase was cloned from the non-Streptomyces actinomycetes, Actinoplanes teichomyceticus ATCC31121. In order to evaluate the effect of the metK expression on antibiotic production in actinomycetes, an expression vector harboring the metK gene was constructed and introduced into Streptomyces lividans TK24 and A. teichomyceticus, and the antibiotic production of the exconjugants was assessed. As a result, it was determined that the expression of metK induced 17-fold and 2.2-fold increases in actinorhodin production from S. lividans TK24 and teicoplanin production from A. teichomyceticus, respectively, compared with the control strains.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.278-285
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• 1999

In order to use heat shock promoter for the detection of toxic substances, dnaK promoter was amplified from E. coli genomic DNA by using a polymerase chain reaction(PCR) followed by sequencing and sub-cloning into the multi-cloning site of the plasmid, pUCD615. The pUCD615 is a broad-host-range vector containing promoterless lux operon originated from V.fischeri. The recombinant plasmid was transfered to E. coli DH5$\alpha$ through electroporation. The recombinant E. coli showed several patterns of bioluminescent responses to ethanol stress. The bioluminescent E. coli also showed responses to other toxic substances including FeK3(CN)6, CdCl2, p-nitrophenol and HgCl2. The increases of RLU(Relative Light Unit) were observed at 100ppm of FeK3(CN)6, 10ppm and 100ppm and 100ppm of CdCl2, 1ppm of 10ppm of p-nitrophenol and at 1ppm of HgCl2.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.154-159
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• 1989

Chromosomal DNA fragments of Bacillus sp. YA-14 isolated from soil as a potent xylan hydrolyzing bacterium, were ligated to a vector plasmid, pBR322, and used to transfer Escherichia coli HB101 cells. The recombinant plasmid pYDC21 was found to enable the transformants to produce xylanase. pYDC21 was found to contain the 3 kb HindIII fragment originated from the Bacillus sp. YA-14 chromosomal DNA by southern hybridization. The optimum temperature and pH for the reaction of xylanse produced by E. coli (pYDC21) were appeared at 50$_7$C and pH 7.0, respectiveiy. the xylanase enzyme was stable between pH 5.0 and 7.0 and maintained stably up to 4$0^{\circ}C$.

• Parasites, Hosts and Diseases
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• v.40 no.1
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• pp.59-64
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• 2002

A Cryptosporidium parvum sporozoite and oocyst λgt11 cDNA library was screened with a hyperimmune rabbit serum that was developed against insoluble fragments of ultrasonicated oocysts. A clone named Cp22.4.1 encoding a protein of 231 amino acids with 4 zinc-finger domains characterized by a Cys-X2-Cys-X4-His-X4-Cys motif was isolated and characterized. There was a complete match between the sequencing data of the coding region of Cp22.4.1 and the corresponding gene at chromosomal level. Cloning in a pBAD-TOPO-TA expression vector permitted to evaluate the antigenicty of the recombinant His-tagged antigen. This antigen was recognized by 2 out of 5 sera from Cruptosporidium immune calves and not by sera from parasite naive animals.

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.169-175
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• 1996

콩 불마름병균 Xanthomonas campestris pv. glycines 8ra는 X. c. pv. vesicatoria에 길항력이 있는 bacteriocin인 glycinecin을 생성 분비한다. Bacteriocin 생성 분비 능력이 있는 콩 불마름병균을 효과적인 생물학적 방제원으로 활용하기 위해서는 좀더 체계적인 연구가 필요하여, bacteriocin 생성에 관계되는 유전자의 분리를 시도하였다. 약 2,000개의 Xanthomonas campestris pv. glycines 8ra cosmid library에서 bacteriocin의 생성 분비 능력을 조사하여 다섯 개의 clone을, pG011, pG0113, pG33과 pG35, 선발하였다. 그중 한 clone pG08을 임의로 선택하여 plasmid DNA를 분리하였다. Plasmid pG08에서 약 6.0 kb의 DNA를 떼어내어 다른 plasmid vector에 넣은 subclone pBL5는 bacteriocin의 생성 분비 능력이 있었다. Plasmid pG08을 제한효소 처리후 다시 접함시켜 만든 몇 개의 subclone과 pBL5의 제한효소 지도를 비교 분석한 결과 약 3.0 kb의 BamHI-HindIII 부분의 DNA가 bacteriocin의 생성에 관계함을 알았다.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.94-97
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• 1990

The restriction cleavage map of multi-copy recombinant plasmid, pJY502 (5.5 kb), carrying the thiostrepton resistance gene (tsr) was determined. Comparison of the restriction pattern with that of Streptomyces plasmids previously demonstrated that pJY502 was novel. The plasmid pJY502 had a broad host range in Streptomyces and contained single BgtII site for cloning purpose. Transformation frequency of pJY502 was $2.2 \times 10^5$ in S. lividans. E. coti-Streptomyces bifunctional plasmid, pJY504, was also constructed.

• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.161-165
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• 1992

The gene encoding the bacteriolytic enzyme cell wall peptidoglycan hydrolase from alkalophilic Bacillus sp. was cloned in E. coli using pBR322 as a vector. A recombinant plasmid, designated pYTR451, was isolated and the size of the cloned HindIII fragment was found to be 4.8 Kb. The cell wall hydrolysis activity of an extract of the E. coli harboring the recombinant plasmid pYTR 451 was detected by SDS- polyacrylamide gel containing 0.2% (w/v) purified cell wall of Bacillus sp. The molecular weight of the enzyme was estimated to be about 27, 000 corresponding to the molecular weight of the Bacillus sp. bacteriolytic enzyme. The recombinant plasmid was found to contain the fragment originated from Bacillus sp. YJ-451 chromosomal DNA by Southern hybridization.

• YAKHAK HOEJI
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• v.46 no.4
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• pp.270-275
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• 2002

The lectin gene from rice was amplified by the polymerase chain reaction. The amplified DNA was inserted into the expression vector pET26b and expressed it as a fusion protein with polyhistidine sequences in Escherichia coli. The recombinant protein was produced by induction with 0.4 mM isopropyl-$\beta$-D-thiogalactopyranoside at 37$^{\circ}C$ and purified by an immobilized metal affinity chromatography. The recombinant protein was found to have lectin activity by the hemagglutination inhibition assay. The hemagglutination activity of the recombinant protein was optimal at pH 4.0-7.0 and was dependent on $Ca^{2+}$ and Mn$^{2+}$.2+/.