• 한국동물위생학회지
• /
• 제25권2호
• /
• pp.117-126
• /
• 2002

Contamination levels of pathogenic microorganisms in 145 cases of beef, which were distributed in Gwangju province, had been investigated in each distributed stage and also monitored by general bacterial count and E coli count index. General bacterial count of beef from the slaughterhouse was 10$^4$cfu/g less than the level of promotion(10 cfu/$\textrm{cm}^2$) and E coli count index was also under the level of 10$^2$cfu/$\textrm{cm}^2$ recommended level of the ministry of agriculture and forestry. Pathogenic microorganisms were detected from 23.2% of samples in the consumption stage, 12.5% in the slaughtering stage and 5.6% in the transporting and processing stage. Staphylococcus aureus was isolated in the largest number and its ratio was 9.0%, listeria monocytogenes 5.5% and salmonella spp 1.4%. There were no samples that bacteria had been detected dually. E coli O157:H7 and campylobacter jejuni were not isolated. In raw and chilled beef, isolation rate of pathogenic microorganisms were 13.3% and 16.5% each. Especially in raw beef, L monocytogenes was. isolated in 3 samples among 30 cases (10%) and S aureus in one sample (3.3%). According to a scale of meat store, isolation rates of pathogenic microorganisms were different. It was 28.6% in the small-scale meat store and 16.7% in the large-scale meat store each. Four cases (16.7%) of S aureus were isolated in the large-scale meat store and seven cases (20.0%) of L monocytogenes and 2 cases (5.7%) of salmonella spp were isolated in the small-scale meat store. S aureus was isolated in two places among 10 feeding facilities of the elementary school. This result shows that the sanitation of elementary school feeding facilities is so poor and more careful policy consideration is needed. Eleven strains of S aureus isolated showed ${\beta}$-hemolysis on blood agar, 1 strain ${\alpha}$-hemolysis, and 1 strain ${\gamma}$-hemolysis. Isolated strains of L monocytogenes were reconfirmed in 560 bp by PCR. Conclusively, these results show that the sanitary condition in the stages of slaughtering, transportation-processing and consumption influences the degree of pathogenic microorganisms contamination in beef severely It is necessary to apply thoroughly hazard analysis critical control point in a process of beef distribution and also to develop rapid test methods for microorganism diagnosis. This effort is very important for the supply of safe and clean meat from farm to table and helpful for the improvement of public health.

• Journal of Microbiology and Biotechnology
• /
• 제22권4호
• /
• pp.535-540
• /
• 2012

${\beta}$-D-Xylosidase (E.C. 3.2.1.37) from Bifidobacterium breve K-110, which hydrolyzes ginsenoside Ra1 to ginsenoside Rb2, was cloned and expressed in Escherichia coli. The ($His_6$)-tagged recombinant enzyme, designated as XlyBK-110, was efficiently purified using $Ni^{2+}$-affinity chromatography (109.9-fold, 84% yield). The molecular mass of XylBK-100 was found to be 55.7 kDa by SDS-PAGE. Its sequence revealed a 1,347 bp open reading frame (ORF) encoding a protein containing 448 amino acids, which showed 82% identity (DNA) to the previously reported glycosyl hydrolase family 30 of Bifidobacterium adolescentis ATCC 15703. The $K_m$ and $V_{max}$ values toward p-nitrophenyl-${\beta}$-D-xylopyranoside (pNPX) were 1.45mM and 10.75 ${\mu}mol/min/mg$, respectively. This enzyme had pH and temperature optima at 6.0 and $45^{\circ}C$, respectively. XylBK-110 acted to the greatest extent on xyloglucosyl kakkalide, followed by pNPX and ginsenoside Ra1, but did not act on p-nitrophenyl-${\alpha}$-L-arabinofuranoside, p-nitrophenyl-${\beta}$-D-glucopyranoside, or p-nitrophenyl-${\beta}$-D-fucopyranoside. In conclusion, this is the first report on the cloning and expression of ${\beta}$-D-xylosidase-hydrolyzing ginsenoside Ra1 and kakkalide from human intestinal microflora.

• Journal of Microbiology and Biotechnology
• /
• 제15권4호
• /
• pp.749-755
• /
• 2005

The ccpA gene encoding catabolite control protein A (CcpA) of Leuconostoc mesenteroides SYl, a strain isolated from kimchi, was cloned, sequenced, analyzed for transcript, and overexpressed in Escherichia coli. The ccpA ORF (open reading frame) is 1,011 bp in size, which can encode a protein of 336 amino acid residues with a molecular mass of 36,739 Da. The transcription start site was mapped at a position 49 nucleotides upstream of the start codon, and promoter sequences were also identified. The putative cre site overlapped with the -35 promoter sequence. The deduced amino acid sequence of the CcpA contained the helix-turn-helix motif found in many DNA-binding regulatory proteins. CcpA from 1. mesenteroides SY1 had $54.6\%$ identity with CcpA from Lactobacillus casei. The Northern blot experiment showed that ccpA was transcribed as a single 1.1 kb transcript, and transcription was repressed when grown on media containing glucose. CcpA was overproduced in E. coli BL21(DE3) cells using the pET expression vector, and purified to an apparent homogeneity. Gel Mobility Shift Assay with purified CcpA and a DNA fragment containing the ere sequence of the $\alpha$-galactosidase gene (aga) from L. mesenteroides SY1 revealed that CcpA bound specifically to the cre site of aga.

• Molecules and Cells
• /
• 제23권3호
• /
• pp.280-286
• /
• 2007

L-asparaginase (EC 3.5.1.1) catalyzes the hydrolysis of the amide group of L-asparagine, releasing aspartate and $NH_4{^+}$. We isolated a low temperature-inducible cDNA sequence encoding L-asparaginase from soybean leaves. The full-length L-asparaginase cDNA, designated GmASP1, contains an open reading frame of 1,258 bp coding for a protein of 326 amino acids. Genomic DNA blotting and fluorescence in situ hybridization showed that the soybean genome has two copies of GmASP1. GmASP1 mRNA was induced by low temperature, ABA and NaCl, but not by heat shock or drought stress. E. coli cells expressing recombinant GmASP1 had 3-fold increased L-asparaginase activity. A possible function of L-asparaginase in the early response to low temperature stress is discussed.

• 한국잠사곤충학회지
• /
• 제34권2호
• /
• pp.20-25
• /
• 1992

유용물질을 생산할 수 있는 곤충 baculovirus expression vector system의 국내 개발을 위하여, Bm-NPV의 다각체 단백질 유전자를 탐색, 클로닝 하고 그 구조를 분석한 결과는 다음과 같다. 1. AcNPV의 다각체 단백질 유전자를 포함하고 있는 EcoRI-Ⅰ fragment내의 0.93kb를 probe로 하여 southern 분석한 결과, BmNPV의 다각체 단백질 유전자는 PstⅠ-F fragment(7.4Kb)에 위치하였다. 2. BmNPV의 다각체 단백질 유전자를 포함하는 PstⅠ-F fragment를 E. coli에 클로닝시켜서 pBmP-F라 명명하고, 다시 southern분석을 통해 subcloning하여 pBmP-H라 명명하였으며 pBmP-H의 제한효소 지도를 작성하였다. 3. pBmP-H의 염기서열분석결과 구조유전자를 포함한 1,259 bp의 염기서열이 결정되었다. Iatrou 등이 보고한 BmNPV 다각체 단백질 유전자의 염기서열과 비교한 결과 10개의 염기서열에서 차이를 보였으며, 74 Val이 Ile로, 76 Asn이 Ser으로 155 Met이 Val로 아미노산 변경된 결과를 보였다.

• 한국동물위생학회지
• /
• 제30권3호
• /
• pp.375-384
• /
• 2007

This study was conducted to investigate the characteristics of brucellosis in Korean native cattle in a farm where bovine brucellosis was confirmed 3 times from September 2006 to March 2007. Of 74 bulls serum samples examined, 21 (28.4%) were positive by Rose-Bengal test (RBT) and Standard tube agglutination test (STAT). In the isolation test from seropositive bulls, B abortus was isolated and identified from 2 specimens (testis, intestinal lymph node) among 6 kinds of specimens including blood, urine, feces and soil. Isolation rate of intestinal lymph node and testis was 25% (3/12 cases) and 16.7% (2/12), respectively. B abortus was also isolated from calves below 12 months old, i.e., 1 isolate (25.0%) was confirmed from testis, 4 (40.0%) from supra-mammary lymph nodes and 1 (25.0%) from intestinal lymph node. All isolates had Brucella specific 16s r-RNA with 905-bp band detected by PCR assay. For the more effective control of bovine brucellosis in korea, this paper would like to suggest that all of bulls and calves should be included in the screening tests.

• Journal of Microbiology and Biotechnology
• /
• 제23권3호
• /
• pp.397-404
• /
• 2013

Paenibacillus xylanilyticus KJ-03 was isolated from soil samples obtained from a field with Amorphophallus konjac plants. A gene encoding xylanase was isolated from KJ-03 and cloned using a fosmid library. The xynA gene encodes xylanase; it consists of 1,035 bp and encodes 345 amino acids. The amino acid sequence deduced from the P. xylanilyticus KJ-03 xylanase showed 81% and 69% identities with those deduced from the P. polymyxa E681 and Paenibacillus sp. HPL-001 xylanases, respectively. The xynA gene comprises a single domain, consisting of a catalytic domain of the glycosyl hydrolase (GH) 10 family. The xynA gene was expressed in Escherichia coli BL21 (trxB), and the recombinant xylanase was purified by Niaffinity chromatography. The purified xylanase showed optimum activity with birchwood xylan as a substrate at $40^{\circ}C$ and pH 7.4. Treatment with $Mg^{2+}$ and $Li^+$ showed a slight decrease in XynA activity; however, treatment with 5 mM $Cu^{2+}$ completely inhibited its activity. The results of the thin layer chromatography analysis indicated that the major hydrolysis product was xylobiose and small amounts of xylose and xylotriose. XynA showed increased activity with oat spelt xylan and birchwood xylan, but showed only slight activity with locust bean gum.

• Journal of Microbiology and Biotechnology
• /
• 제17권1호
• /
• pp.37-43
• /
• 2007

A gene encoding inulin fructotransferase (di-D-fructofuranose 1,2': 2,3' dianhydride [DFA III]-producing IFTase, EC 4.2.2.18) from Bacillus sp. snu-7 was cloned. This gene was composed of a single, 1,353-bp open reading frame encoding a protein composed of a 40-amino acid signal peptide and a 410-amino acid mature protein. The deduced amino acid sequence was 98% identical to Arthrobacter globiformis C11-1 IFTase (DFA III-producing). The enzyme was successfully expressed in E. coli as a functionally active, His-tagged protein, and it was purified in a single step using immobilized metal affinity chromatography. The purified enzyme showed much higher specific activity (1,276 units/mg protein) than other DFA III-producing IFTases. The recombinant and native enzymes were optimally active in very similar pH and temperature conditions. With a 103-min half-life at $60^{\circ}C$, the recombinant enzyme was as stable as the native enzyme. Acidic residues and cysteines potentially involved in the catalytic mechanism are proposed based on an alignment with other IFTases and a DFA IIIase.

• Journal of Animal Science and Technology
• /
• 제49권3호
• /
• pp.295-302
• /
• 2007

본 연구는 한우 24두의 혈액으로부터 geno- mic DNA를 추출하여 leptin 유전자의 intron 1부터 3’-UTR 부분까지의 염기 서열을 결정하여 총 25개의 SNPs을 발굴하였다. 발굴된 SNPs 중 16개는 기존의 서양 품종에서도 발견되는 것으로 그 빈도는 대부분의 경우 유사하였으나, 서로 유의성이 있도록 상이한 경우도 있었다. Intron 1의 T1064G, exon 2에서 발견된 nonsynonymous SNP(T1163A, Val to Glu)과 exon 3의 C3011G 및 G3256A(Gly to Asp) SNPs은 기존에 보고되지 않은 한우에서 새롭게 발견된 것으로 종 간의 차이를 나타내는 것으로 사료된다. 이러한 한우의 SNPs 정보는 한우의 유전형을 결정하고, 도체 및 육질 형질 등 중요 경제 형질과의 연관 분석을 통하여 중요한 유전자 표지 확보 및 한우 판별 등의 응용에 이용될 수 있을 것으로 사료된다.

• 분석과학
• /
• 제30권6호
• /
• pp.329-337
• /
• 2017

A major concern regarding most auto-repair shops in residential areas is the emission of odorous volatile organic compounds (VOCs) into the local atmosphere, especially during painting operations. VOCs contribute to poor local air quality and are responsible for the perceived odor and discomfort experienced by local residents. Sixteen major VOCs (6 aromatic hydrocarbons and 10 aliphatic carbonyl compounds) were selected as potential target compounds. The site was an auto-repair shop located in a central region of Seoul, South Korea, where the air quality of the site has been a subject of residents' complaints. The sampling points were as follows: 1) in the painting booth with new (NB) or old (OB) removal system, (2) in the exhaust duct after new (ND) or old (OD) odor removal filter, and (3) 2 m below the discharge vent (4 m above the ground) (outdoor air, OA). Each sample was coded: (1) before painting (BP), (2) during painting (DP), and (3) after painting (AP). The toluene level in the duct with the new removal filter during painting (ND-DP) was 1.5 ppm (v/v), while it was 3.8 ppm (v/v) in the right duct with an old removal filter during painting (OD-DP). Accordingly, the effect of filter replacement was reflected by differences in VOC levels. Therefore, accurate monitoring of odorous VOCs is an important step to reduce odor nuisance from local sources.