• The Microorganisms and Industry
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• v.14 no.1
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• pp.17-20
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• 1988

A genetic analysis of the complex Bacillus subtilis transcriptional apparatus is essential to understand the function, regulation, and interaction of the transcriptase components during growth and sporulation. This approach in Escherichia coli has uncovered fundamental mechanisms regulating gene expression Cole and Nomura, 1986; Lindahl and Zengel, 1986) and an analysis of the B. subtilis transcriptase will allow comoparison of the E.coli system to another bacterium that has evolved under different selective pressures. To this end we used antibody probes to isolate the alpha, beta, and beta' core subunit genes from a .lambda.gtill expression vector library. To address the question of function ans regulation of the minor sigma factors that confer promoter specifity on the polymerase core (Losick et al., 1986), we used the same approach to isolate the gene for the 37,000 dalton sigma factor, sigma-37.

• BMB Reports
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• v.38 no.1
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• pp.24-27
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• 2005

The role of 3' exonuclease excision in DNA polymerization was evaluated for primer extension using inert allele specific primers with exonuclease-digestible ddNMP at their 3' termini. Efficient primer extension was observed in amplicons where the inert allele specific primers and their corresponding templates were mismatched. However, no primer-extended products were yielded by matched amplicons with inert primers. As a control, polymerase without proofreading activity failed to yield primer extended products from inert primers regardless of whether the primers and templates were matched or mismatched. These data indicated that activation was undertaken for the inert allele specific primers through mismatch proofreading. Complementary to our previously developed SNP-operated on/off switch, in which DNA polymerization only occurs in matched amplicon, this new mutation detection assay mediated by $exo^+$ DNA polymerases has immediate applications in SNP analysis independently or in combination of the two assays.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.308-313
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• 1998

Reverse transcription and polymerase chain reaction (RT-PCR) techiniques were used to identification and differentiation of cucumber mosaic virus isolated from Forsythia koreana (CMV-Fk). RT-PCT used by two set of 20-mer primers one was CMV-common primers and another was CMV subgroup I-specific primers designed in a conserved region of the 3' end of CMV RNA3, amplified about 490 bp and 200 bp DNA fragments from CMV-Fk, respectively. CMV could be detected by RT-PCR at a dilution as low as 10-4 in forsythia crude sap extracts. Restriction enzyme analysis of RT-PCR products using EcoRI and MspI showed that CMV-Fk belonged to CMV subgroup I. But, analysis of RNA fingerprinting by arbitrarily primed polymerase chain reaction (RAP-PCR) showed heterogeneity of RNA3 between CMV-Fk and CMV-Y as a member of subgroup I.

• Microbiology and Biotechnology Letters
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• v.28 no.6
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• pp.316-321
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• 2000

Role of enterotoxin from Salmonella in pathogenesis is not know. Enterotoxin gene from Salmonella typhimurium(stn) encodes a 29kDa toxin that has no homology to any other known enterotoxins. Expression of stn is enthanced upon contact with epithelial cell but not all strains having the stn gene express Stn, Based on PCR analysis, we found that all 36 clinical strains of Salmonella isolated in Korea tested carried the stn gene. To understand the trgulation of the stn transcription, the expression of stn was studies in vitro. RNA polymerase was purified by polymin P fraction-ation, DNA-agarose affinity chromatography, and Mono-Q ion exchange chromatography from Salmonella. The expression of stn was inhibited by cAMP·CRP complex by about 50%.

• Journal of Microbiology and Biotechnology
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• v.4 no.1
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• pp.20-23
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• 1994

The polymerase chain reaction was used to study the genes inducible under stress from the heavy metal cadmium. Schizosaccharomyces pombe, grown in the presence or absence of sublethal concentration of cadmium, was isolated to purify the total RNAs. The Induced RNA Random Fishing (IRRF) method in which random oligonucleotides were used as primers was applied to the identification of cadmium-induced gene expressions. A PCR-DNA product of 400-bp was cloned and sequenced. Computer analysis showed that this DNA has no homology with any known DNA sequences in GenBank or EMBL databases. The induction of this gene was confirmed by Northern blot analysis of total RNAs isolated from both cadmium-treated and untreated yeast cells.

• Journal of Microbiology and Biotechnology
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• v.1 no.1
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• pp.45-49
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• 1991

The complete nucleotide sequence of alkalophilic Bacillus sp. K-17 $\beta$-xylosidase gene and its flanking regions were established. A 1263-bp of an open reading frame for $\beta$-xylosidase was observed. The molecular weight (50, 521 dalton), deduced from the nucleotide sequence of $\beta$-xylosidase gene, agreed with the result obtained by SDS-polyacrylamide gel electrophoresis of the purified enzyme (51, 000 dalton). The Shine-Dalgarno sequence, 5'-GAGGAGG-3', was found 8 bp upstream of the initiation codon ATG. The -10 sequence (TAAAAT) in the promoter region for $\beta$-xylosidase gene was similar to the consensus sequence for Bacillus subtilis RNA polymerase, whereas the -35 sequence (TCGATCA) different from all the known -35 regions in the promoter for Bacillus subtilis RNA polymerase.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.1038-1041
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• 2009

Aflatoxins are secondary metabolites produced by the aflatoxigenic fungi in suitable conditions. Saffron, Crocus sativus, is the most expensive spice in the world. Saffron is normally contaminated with soil and hand microflora during harvest and post-harvest operations. In this study, rapid assessment of aflatoxigenic fungi in saffron was accomplished using polymerase chain reaction. In total, 37 market samples were assayed in order to isolate aflatoxin-producing fungi. The 18.9% of the total samples were contaminated with aflatoxigenic fungi. Our results also show that most of the isolated fungi were saprophytes which are normally originated from soil during harvest and postharvest process.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.264-266
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• 2000

A new GFP-based T-vector for cloning of PCR products was developed by using a green fluorescent protein (GFP) as a mafker. In order to facilitate the DNA inserts, multiple restriction sites, SP6 and T7 RNA polymerase promoter sites, were introduced close to the PCR DNA insertion site of a pCRGv vector. The XcmI-digested pHNT plasmid can be used to clone a 3' A-overhanged PCR DNA amplified by Taq DNA polymerase. A potential method of easing some difficulties from its use along with its cost savings proveded by this vector are likely to lead to the replacement of other T-vectors for PCR DNA cloning.

• Mycobiology
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• v.42 no.2
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• pp.109-113
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• 2014

During a survey of marine fungi from the waters surrounding Jeju Island, Korea, several Penicillium strains were isolated from seawater and marine sponges. Based on morphological characteristics and phylogenetic analyses of the internal transcribed spacer and RNA polymerase subunit II, four strains were identified as Penicillium antarcticum, a fungus that, to the best of our knowledge, had not been previously reported in Korea. Here, we provide detailed descriptions of the morphological characteristics and extracellular enzyme activities of the four strains.

• Journal of Oral Medicine and Pain
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• v.20 no.2
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• pp.515-528
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• 1995

The human genomic deoxyribonucleic acid(DNA) was extracted from the pulp, dentin of 22 teeth by clelex, phenol methods. Samples of the tooth-derived DNA were amplified by polymerase chain reaction(PCR), electrophosed for sex determination by detection of X-Y homologus amelogenin gene and D1S80 locus detection The following results have been achieved. 1. Chelex and phenol method are effective to sex determination in the pulp and dentin 2. Chelex method is not suitable for detection of D1S80 locus. 3. Concentration and purity of DNA for teeth using chelex method is lower than using phenol method. From the above investigation, chelex method is simple, rapid for sex determination, but it is not suitable for detection of VNTRs.