• Journal of Microbiology and Biotechnology
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• 제1권1호
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• pp.37-44
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• 1991

A shuttle promoter-probe vector, pEB203, was derived from pBR322, pPL703 and pUB110. Using the vector, a useful DNA fragment, 319 bp EcoRI fragment, having strong promoter activity has been cloned from Bacillus subtills chromosomal DNA. Selection was based on chloramphenicol resistance which is dependent upon the introduction of DNA fragments allowing expression of a chloramphenicol acetyl transferase gene. The nucleotide sequence of the 319 bp fragment has been determined and the putative -35 and -10 region, ribosome binding site, and ATG initiation codon were observed. This promoter was named EB promoter and the resultant plasmid which can be used as an expression vector was named pEBP313. The crystal protein gene from B. thuringiensis subsp. kurstaki HD-73 was cloned downstream from the EB promoter without its own promoter. When the resultant plasmid, pBT313, was introduced into Escherichia coli and B. subtilis, efficient synthesis of crystal protein was observed in both cells, and the cp gene expression in B. subtilis begins early in the vegetative phase. The cell extracts from both clones were toxic to Hyphantria cunea larvae.

• Journal of Microbiology and Biotechnology
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• 제4권4호
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• pp.264-269
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• 1994

To determine the nucleotide sequence of the ds RNA segment B containing the RNA dependent RNA polymerase (RdRp) gene of the DRT strain of infectious pancreatic necrosis virus (lPNV), the cDNA of the ds RNA segment B of the DRT strain of IPNV was synthesized using the reverse transcriptase (RT)-polymerase chain reaction (PCR) and its cDNA nucleotide sequence was determined. The DRT segment B was 2, 783 bp long and contained only a single long open reading frame (ORF) of 2, 535 bp in length. This ORF nucleotides encoded the VPl protein, the putative RdRp of IPNV. The VPl protein comsisted of 845 amino acids. The molecular weight of the RdRp, as deduced from the nucleotide sequence, is 94, 426. The nucleotide sequence of the ORF of the DRT showed 89.7% homology to the Jasper strain, but 80.8% to the Sp strain. The amino acid sequence of the ORF of the DRT sho.wed 97.6% homology to the Jasper strain, but 88.7% to the Sp strain. The conserved GTP-binding motif was detected in VPl protein.

• International Journal of Oral Biology
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• 제42권3호
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• pp.143-147
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• 2017

In a previous study, Peptoniphilus mikwangii was isolated from the human oral cavity as a new species. The purpose of this study was to develop P. mikwangii-specific PCR primers. The PCR primers were designed, based on the nucleotide sequence of 16S ribosomal RNA (16S rDNA). The specificity of the primers was tested using genomic DNAs of 3 strains of P. mikwangii and 27 strains (27 species) of non-P. mikwangii bacteria. The sensitivity of primers sensitivity was determined using PCR, with serial dilutions of the purified genomic DNAs (4 ng to 4 fg) of P. mikwangii KCOM $1628^T$. The data showed that P. mikwangii-specific qPCR primers (B134-F11/B134-R1 & B134-F5/B134-R5) could detect only P. mikwangii strains, and 400 fg or 40 fg of P. mikwangii genome DNA. These results suggest that PCR primers are useful in detecting P. mikwangii from the oral cavity.

• 한국어병학회지
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• 제31권2호
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• pp.101-107
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• 2018

여윔증상이 나타난 양식장(farm-B 및 farm-C)의 넙치 및 여윔증상이 나타나지 않은 양식장(farm-A) 넙치의 각 내부 장기(신장, 장, 비장, 뇌 및 간)를 대상으로 점액포자충 Parvicapsula sp.의 양적 분석을 real-time PCR 방법을 사용하여 각각 실시하였다. 여윔증상을 보였던 farm-C의 넙치 신장에서 가장 높은 DNA copy number ($1.7{\times}10^7copies/mg$ tissue)를 보였고, farm-B의 넙치에서는 모든 내부 장기에서 낮은 수치가 나타났으며, farm-A의 넙치에서는 모든 내부 장기에서 음성 결과를 나타내었다. 동일한 시료를 사용한 PCR 및 병리조직학적 분석에서도 real-time PCR에서의 결과와 같은 양상을 보였다.

• 한국미생물·생명공학회지
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• 제49권3호
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• pp.440-448
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• 2021

Helicobacter pylori (H. pylori) establishes long-term infections associated with severe gastric diseases such as peptic ulceration and gastric cancer. Exposure to an antibacterial agent can help regulate the expression levels of its pathogenic genes. In this study, we analyzed the transcriptional changes in H. pylori genes induced by β-caryophyllene. We used next-generation sequencing (NGS) to analyze RNA expression changes, and reverse transcription-polymerase chain reaction (RT-PCR) was performed as required to verify the results. The NGS results showed that 30 out of 1,632 genes were expressed differentially by β-caryophyllene treatment. Eleven genes associated with DNA replication, virulence factors, and T4SS components were significantly downregulated. RT-PCR confirmed that treatment reduced the expression levels of 11 genes. RT-PCR showed the reduced expression of 11 genes (dnaE, dnaN, holB, gyrA, cagA, vacA, secA, flgE, virB2, virB4, and virB8) following β-caryophyllene treatment. These results suggest that β-caryophyllene can modulate various H. pylori pathogenic determinants and be a potential therapeutic agent for H. pylori infection.

• Journal of Microbiology and Biotechnology
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• 제7권5호
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• pp.299-304
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• 1997

Expression in the periplasm of Escherichia coli of cloned heavy and light chain cDNAs for Fab fragment of a murine monoclonal antibody MabB9 (${\gamma}2b$, K), specific for human plasma apolipoprotein B-100 of LDL, was studied. For the purpose, a vector for two-cistronic expression of the heavy chain cDNA, at the 5' terminus, and light chain cDNA, at the 3' terminus, was constructed using the signal sequences, pelB (for heavy chain) and ompA (for light chain) in a pET vector system. The constructed vector was transformed into E. coli BL21(DE3). The expressed heavy chain (25 kDa) and light chain (23 kDa) of the antibody molecule were detected in total cell extracts as well as in the periplasmic extracts of E. coli.

• Journal of Microbiology and Biotechnology
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• 제16권3호
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• pp.431-437
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• 2006

Aero-tolerant microorganisms were isolated from healthy Koreans over the age of 95 years. The microorganisms were then identified based on their morphological and biochemical characteristics and 16S rDNA sequences. The growth properties of the isolated strains were investigated in kimchi. The characteristics of kimchi containing the microorganisms were studied microscopically, physicochemically, and organoleptically. Among 7 aero-tolerant strains, a strain with a 16S rDNA sequence exhibiting 99% homology with Bifidobacterim animalis strain B83 was selected and named B. animalis DY-64. The new strain showed a better acid resistance and salt resistance (p<0.05) than B. animalis ATCC 25527. After 15 days of fermentation in kimchi, the viability of B. animalis DY-64 was about 10%, and the kimchi had a better overall edible quality than conventional kimchi. Thus, it was found that the application of B. animalis DY-64 to kimchi preparation produced a good overall edible quality.

• 대한임상검사과학회지
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• 제44권3호
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• pp.142-146
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• 2012

Hepatitis B surface antigen (HBsAg) seroclearance is a rare event in chronic hepatitis B virus (HBV) infection which acquires the disease early in life. A case study have examined with asymptomatic chronic hepatitis B carrier who exhibits HBsAg seroclearance in anti-HBe positive. We comprehensively studied the biochemical, virological and clinical aspects of a patient with HBsAg seroclearance. Liver biochemistry, serological markers, serum HBV DNA levels, and development of clinical complications were monitored. Mutation of hepatitis B virus is suspected serum HBsAg detected by the HBsAg assay systems of VITROS (OrthoClinical Diagnostics, USA), AxSYM (Abbott Laboratories, USA), Elecsys (Roche Diagnostics, Germany) and ADVIA Centaur (Bayer Diagnostics, USA). These four immunoassays showed negative results. Also, the patient had undetectable serum HBV DNA. Therefore, no mutation within the "a" determinant of HBsAg, which might escape detection from HBsAg immunoassay were found. Natural seroclearance was confirmed.

• KSBB Journal
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• 제13권4호
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• pp.383-390
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• 1998

Bacillus subtilis DT134 was resistant to 50-fold higher concentration of cadmium ions (Cd2+) than cadmium-sensitive B. subtilis BD224 in Luria Broth (LB) medium. Minimal inhibition concentration test in LB agar plates also showed similar results. The elevated cadmium resistance of B. subtilis DT134 strongly suggested a possible existence of cadmium resistance gene in it. Southern blot with Staphylococcus aureus cadA gene fragment (757 bp NlaIV-XmnI cadA DNA fragment) as probe was carried out to test the existence and similarity of the gene. In high stringency condition, there was no detectable signal, but in low stringency, a strong signal specific to the cadA probe could be detected. These results strongly suggested that there was some similarity between total DNA of B. subtilis DT134 and S. aureus pl258 in terms of cadmium resistance gene and the resistance mechanism might be an efflux mechanism. The subsequent efflux experiment showed that the cadmium resistance mechanism of B. subtilis DT134 was also due to the efflux of cadmium.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1994년도 Proceedings of International Symposium on BIOLOGICAL CONTROL OF PLANT DISEASES Korean Society of Plant Pathology
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• pp.75-85
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• 1994

Biocontrol is playing a more and more important role in plant disease management. Evidences show that there are optimum prospects for people to apply biocontrol approach to control plant disease or to study the mechanism of antagonism.“The study of Antagonistic Protein of Bacillus spp.to Xanthomonas oryzae pv. oryzae”has been worked in our laboratory since 1986. One hundred and thirty antagonistics bacteria were screened out, most of them belonged to Bacillus spp., and showed very strong inhibitive effect to various plant pathogens. Nine antagonistic proteins (peptides) were purified (P11-I, P11-II, B8, B826-I, B826-II, A30-I, A30-II, G35). Two antagonistic protein related DNA fragments (B826-I, A30-II) were cloned and sequenced. B826-I DNA fragment composed by 905 bp, and it contained two ORF encoding 95, and 54 amino acids, respectively. By using Rifr and Kamr as the selective markers, we found the bacteria could colonize on rice leaf for at least 40 days. In greenhouse the antagonistic bacteria showed certain degree of control efficiency.