• BMB Reports
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• 제37권2호
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• pp.254-259
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• 2004

The wild-type and temperature-sensitive (ts) repressor genes were cloned from the temperate mycobacteriophage L1 and its mutant L1cIts391, respectively. A sequencing analysis revealed that the $131^{st}$ proline residue of the wild-type repressor was changed to leucine in the ts mutant repressor. The 100% identity that was discovered between the two DNA regions of phages L1 and L5, carrying the same sets of genes including their repressor genes, strengthened the speculation that L1 is a minor variant of phage L5 or vice versa. A comparative analysis of the repressor proteins of different mycobacteriophages suggests that the mycobacteriophage-specific repressor proteins constitute a new family of repressors, which were possibly evolved from a common ancestor. Alignment of the mycobacteriophage-specific repressor proteins showed at least 7 blocks (designated I-VII) that carried 3-8 identical amino acid residues. The amino acid residues of blocks V, VI, and some residues downstream to block VI are crucial for the function of the L1 (or L5) repressor. Blocks I and II possibly form the turn and helix 2 regions of the HTH motif of the repressor. Block IV in the L1 repressor is part of the most charged region encompassing amino acid residues 72-92, which flanks the putative N-terminal basic (residues 1-71) and C-terminal acidic (residues 93-183) domains of L1 repressor.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.816-821
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• 2004

A reliable molecular phylogenetic method to identify Hericium erinaceum, the most industrially valuable species in the Hericium genus, was established. Sequencing and phylogenetic analyses of the PCR-amplified ITS and 5.8S rDNA from Hericium fungi, including 6 species and 23 isolates, showed that variation in nucleotide sequences and size exists in both ITS1 and ITS2 regions, but not in the 5.8S region. These two ITS regions provided different levels of information on the relationship of H. erinaceum to other Hericium species. Based on the ITS1 sequence, both the parsimony and neighbor joining trees clearly distinguished Asian H. erinaceum isolates from other Hericium species and isolates. The intraspecific divergence of the ITS2 region was suitable to dissect the Asian H. erinaceum isolates into a few groups.

• Preventive Nutrition and Food Science
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• 제17권1호
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• pp.64-70
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• 2012

Bacilli with fibrinolytic activities were isolated from traditionally-prepared Meju and some of these strains showed strong antifungal activities. One isolate, MJ1-4, showed the strongest antifungal activity. MJ1-4 and other isolates were identified as B. amyloliquefaciens strains by recA gene sequencing and RAPD-PCR results. B. amyloliqufaciens MJ1-4 efficiently inhibited an Aspergillus spp.-producing aflatoxin B1 ($AFB_1$) and a Penicillium spp.-producing ochratoxin (OTA) in addition to other fungi. Antifungal activity of B. amyloliquefaciens MJ1-4 culture reached its maximum (40 AU/mg protein) in LB or TSB medium around 48 hr at $37^{\circ}C$. Antifungal activity of the concentrated culture supernatant was not decreased significantly by protease treatments, implying that the antifungal substance might not be a simple peptide or protein. Considering its antifungal and fibrinolytic activities together, B. amyloliquefaciens MJ1-4 can serve as a starter for fermented soyfoods such as Cheonggukjang and Doenjang.

• Archives of Pharmacal Research
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• 제29권1호
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• pp.88-95
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• 2006

Analysis of molecular nature of mitochondrial DNA (mtDNA) could be powerful marker for anthropological studies of modern populations. While population genetic studies on mtDNA have been reported for several ethnic groups, no such study has been documented for the Korean population. We surveyed mtDNA polymorphisms in the HVS I of noncoding D-loop region and its upstream region from 430 unrelated healthy Korean population by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing analysis. PCR product with 2,790 bp spanning the specific mtDNA region (mt13715-16504) was subjected to RFLP analysis using 6 restriction enzyme (Hinf I, Hae III, Alu I, Dde I, Mbo I, Rsa I). On the PAUP analysis of PCR-RFLP results, 38 mtDNA haplotypes (Hap 1-38) were detected in the Korean populations, which were classified into 11 haplogroups (Grp 1-11) of related haplotypes encompassing all 38 haplotypes. In comparison of sequencing data with Anderson's reference sequence, the transition type was more prevalent than the transversion type. Insertions or deletions were not found. In addition, three of the polymorphic sites (A16240C, A16351G, G16384A) in HVS-I region are determined newly. The polymorphic sites were distributed randomly in the region, though the frequency at each site was variable. Thus, this research might be required for the genealogical study of Orientals.

• 전기전자학회논문지
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• 제20권3호
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• pp.251-259
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• 2016

본 논문에서는 순차바이어스와 스위칭 타임 튜닝기법을 통한 반도체 송수신모듈(TRM : Transmitter and Receiver Module)의 강건성 향상 방법에 대해 기술한다. 기존의 회로설계는 TRM의 소형화로 인한 송신출력신호가 수신기로 유기되어 최소수신감도(MDS : Minimum Detection Signal) 개선에 초점을 맞추어졌으나, 평균고장시간(MTBF : Mean Time Between Failure)을 만족하지 못하고 빈번히 고장이 발생하는 문제가 있었다. 본 연구는 이러한 현상을 개선하는 방법으로 순차바이어스 및 스위칭 타임 튜닝기법을 제안한다. 첫 번째로 주요 고장증상 수집 및 원인을 추론하였으며, 두 번째로 개선방법을 도출하고 시스템에 적용하여 효과를 검증하였다. 제안한 방법을 적용하여 격리도 부족에 따른 빈번한 고장증상이 해소되었다.

• Weed & Turfgrass Science
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• 제4권1호
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• pp.18-25
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• 2015

DNA 바코드는 게놈 DNA의 단편을 이용해 형태적 지식없이 종을 동정하는 방법으로 전 세계적으로 최근에 많이 이용하고 있으며 고등식물에서는 엽록체 rbcL과 matK 유전자를 이용하고 있다. 본 연구에서는 표준 식물 바코드마커와 핵 ITS 부위를 이용하여 국내 포아풀아과 잡초 16속 29종 163생태형의 바코드 데이터를 생산하는 것을 목적으로 하였다. 더불어 포아풀아과의 바코드에서 각 마커의 효율성도 조사하였다. 바코드 결과 PCR 증폭과 염기서열 분석성공률은 rbcL에서 가장 높았으며 matK에서 가장 낮았다. 반대로 바코드 갭은 matK에서 가장 높은 반면 rbcL에서 가장 낮았으며, 종 식별 해상력은 matK에서 가장 높고, ITS에서 가장 낮았다. 그러나 바코드 갭과 종 식별 해상력이 가장 높은 matK를 포아풀아과에서 바코드 마커로 이용하는 것은 너무 낮은 PCR 증폭과 염기서열 분석성공률(58.3%) 때문에 고려해야할 것으로 생각된다. 단일마커로 rbcL과 ITS는 포아풀아과의 바코드에 적절하게 이용될 수 있으며, 두 마커를 조합으로 이용하면 공통으로 분석된 샘플에 따라 바코드 갭과 종 식별 해상력을 높일 수 있었다. 포아풀아과의 바코드데이터는 미국의 국립생물공학정보센터에 기탁하여 genbank 번호를 부여받아 공개하였다.

• Mycobiology
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• 제31권4호
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• pp.196-199
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• 2003

A very reliable and specific method for the identification of fungi in ectotrophic mycorrhizal symbiosis was developed using a specific PCR assay based on the amplification of the ITS1 region. To obtain specific data, an ITS-diagnostic assay was carried out that reveals genera and species specific sequences. Here, an application of one method is presented, which covers the identification of pure mycelia, basidiocarps as well as mixed samples such as ectomycorrhizal roots that were mingled with remains of the host plant. For this purpose a protocol was established that allowed the extraction of DNA from single mycorrhizal roots. In order to perform a specific ITS analysis we generated a new ITS-primer(ITS8) by a multiple alignment of five different genera and species of mycorrhizal fungi. The utilization of ITS1 and ITS8 resulted in specific PCR amplicons, which were characterized by sequencing without purification steps, even when the template DNA was associated with roots.

• Journal of Photoscience
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• 제8권2호
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• pp.55-60
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• 2001

Ginseng (Panax genus) is one of the most medicinally important genera and consists of highly regarded medicines. Among the species of Panax, the ginseng species is widely known to have most medicinal quality. P. ginseng has 3 varieties, Jakyung, Chunggyung and Hwangsook, discovered in nature with different colors of stem and fruit, Jakyung has two cultivars, Yunpoong and Chunpoong. Rigorous phylogenetic analysis of these varieties and cultivars has been conducted with sequencing of rDNA region. The sequences of ITS1, ITS2 of every varieties and cultivars within P. ginseng were identical. The sequence of 5.8S rDNAs of Hwangsook variety were different from the sequences of 5.8S rDNAs of others by only one base pair at nucleotide position 14. In phylogenetic analysis and predicted RNA secondary structure study, it is assumed that evolution has proceeded from Hwangsook to other varieties. recently.

• Mycobiology
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• 제33권2호
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• pp.109-112
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• 2005

The internal transcribed spacer (ITS) regions including the 3'-end of 18S rRNA gene, 5.8S rRNA gene and the 5'-end of the 28S rRNA gene of Rhizopus spp. were amplified by PCR and analyzed by DNASIS program. Length polymorphism of these region ranged from 564 bp in R. oryzae to 789bp in R. stolonifer. The length and sequence of 5.8S was very conserved with $154{\sim}155\;bp$. The sequence of ITS2 was more variable than that of ITS1. The base substitution rates were ranged from 0 to 0.6069 per site, and higher rate was found in R. stolonifer. In general, transition was usually more frequent than transversion. On the basis of sequencing results, four groups were clustered with value of 61.9% similarity; R. oryzae, R. micros pores, R. homothallicus, and R. stolonifer groups.

• Journal of Veterinary Science
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• 제24권3호
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• pp.38.1-38.12
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• 2023

Background: Poor disease management and irregular vector control could predispose sheltered animals to disease such as feline Bartonella infection, a vector-borne zoonotic disease primarily caused by Bartonella henselae. Objectives: This study investigated the status of Bartonella infection in cats from eight (n = 8) shelters by molecular and serological approaches, profiling the CD4:CD8 ratio and the risk factors associated with Bartonella infection in shelter cats. Methods: Bartonella deoxyribonucleic acid (DNA) was detected through polymerase chain reaction (PCR) targeting 16S-23S rRNA internal transcribed spacer gene, followed by DNA sequencing. Bartonella IgM and IgG antibody titre, CD4 and CD8 profiles were detected using indirect immunofluorescence assay and flow cytometric analysis, respectively. Results: B. henselae was detected through PCR and sequencing in 1.0% (1/101) oral swab and 2.0% (1/50) cat fleas, while another 3/50 cat fleas carried B. clarridgeiae. Only 18/101 cats were seronegative against B. henselae, whereas 30.7% (31/101) cats were positive for both IgM and IgG, 8% (18/101) cats had IgM, and 33.7% (34/101) cats had IgG antibody only. None of the eight shelters sampled had Bartonella antibody-free cats. Although abnormal CD4:CD8 ratio was observed in 48/83 seropositive cats, flea infestation was the only significant risk factor observed in this study. Conclusions: The present study provides the first comparison on the Bartonella spp. antigen, antibody status and CD4:CD8 ratio among shelter cats. The high B. henselae seropositivity among shelter cats presumably due to significant flea infestation triggers an alarm of whether the infection could go undetectable and its potential transmission to humans.