• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1183-1186
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• 2011

The unique Br signature was utilized for C-terminal amino acid sequencing of model peptides. C-terminal carboxyl group was selectively derivatized in peptides, containing side chain carboxyl group, using 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride (EDC) and Br was introduced using 4-bromophenylhydrazine hydrochloride (BPH) in a one pot reaction. Matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) tandem mass spectra were obtained carrying the Br signature in the y-series ions. The Br signature facilitated C-terminal sequencing and discrimination of C-terminal carboxyl groups in the free acid and amide forms.

• Proceedings of the Microbiological Society of Korea Conference
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• 2002.10a
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• pp.15-21
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• 2002

Terminal-restriction fragment length polymorphism (T-RFLP) analysis has been optimized by using in vitro model community composed of genomic DNAs of known bacterial strains and has been applied to assess the bacterial community structure in marine sediments. The specific fluorescence-labeled terminal restriction fragments (T-RFs) between 39 and 839 base long specifying each strain were precisely measured for known bacterial strains. The addition of a co-solvent (dimethylsulfoxide or glycerol) into PCR reactions has reduced differential PCR amplification. Comparative bacterial community structure was investigated for pristine and polluted sediments. A complex T-RFLP pattern showing complex bacterial community structure was obtained in the pristine sediment, whereas simple T-RFLP pattern (low bacterial diversity) was shown in polluted sediments where caged aquaculture has been conducted for several years. The results of T-RFLP analysis were compared with that of cloning and sequencing 16S rDNA clones from the same sediments. Sequence analysis of 16S rDNA clones (72) of the pristine sediment revealed a diverse collection of lineages, largely of the class Proteobacteria ($6\%$ alpha subdivision, $46\%$ gamma subdivision, $13\%$ delta subdivision, and $3\%$ epsilon subdivision), Nitrospina $(8\%)$, high G+C gram positive $(8\%)$, Verrucomicrobia $(7\%)$, and Planctomycetes $(6\%)$. In the contaminated sediments, 17 $(59\%)$ of the 16S rDNA clones (29) were related to Campylobacter and symbiont of Rimicaris exoculata belonging to epsilon subdivision of Proteobacteria. The results obtained indicated that T-RFLP analysis is a rapid and precise technique for comparative bacterial community analysis.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.168.3-169
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• 2000

No Abstract, See Full Text

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.175-178
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• 1993

Alkaline .alpha.-amylase expressed in the transformant, Baciollus subtills MB809, containing alkaline amylase gene cloned from alkalophilic Bacillus sp. AL-8, was purified through for step separation processes. The purified alkaline .alpha.-amylase had molecular weight of app[roximately 59, 000 daltons on SDS-PAGE and Sephaex G-100 gel filtration. Amino acid sequence of terminal portion of the enzyme was analyzed with pure amylase eluted form the SDS-PAGE gel. N-terminal amino acid sequence of .alpha.-amylase was determined by the Edman degradation method and resulted in $NH_{2}$-ser-thr-ala-pro-ser-(ile)-lys-ala-gly-thr-(ile)-leu. For C-terminal amino acid sequencing, purified .alpha.-amylase was digested with carboxypuptidase A and B, and reverse-phase HPLC gradient elution system resulted in -thr-trp-pro-lys-COOH.

• Journal of Life Science
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• v.8 no.5
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• pp.571-575
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• 1998

The nerve system specific protein of Drosophila melanogaster was produced by using heads of flies as the antigen. The monoclonal antibody 6H6 recognized the disabled molecules that a kind of tyrosine kinase substrate by expres-sion cDNA library screening method. At the same time, the antibody also specifically recognized C-terminal region of disabled protein from 7427 to 8761bp by DNA sequencing. In early embryos, the localization of antigen appeared in the central nerve system. In adult flies, the antigen showed specific localization on the axon of optic nerve, cerebral nerve and thoracic nerve, and they also expressed on the muscular nerve. The molecules of disabled are expected to carry an important function in developing central nerve system. In adult flies, it is suggested that the disabled molecules have a role for muscular nerve as well as neural axon.

• Journal of Veterinary Science
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• v.22 no.6
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• pp.66.1-66.9
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• 2021

Background: Maedi/Visna virus (MVV) is a contagious viral pathogen that causes considerable economic losses to the sheep industry worldwide. Objectives: In China, MVV has been detected in several regions, but its molecular characteristics and genetic variations were not thoroughly investigated. Methods: Therefore, in this study, we conducted next-generation sequencing on an MVV strain obtained from northwest China to reveal its genetic evolution via phylogenetic analysis. Results: A MVV strain obtained from Inner Mongolia (NM) of China was identified. Sequence analysis indicated that its whole-genome length is 9193 bp. Homology comparison of nucleotides between the NM strain and reference strains showed that the sequence homology of gag and env were 77.1%-86.8% and 67.7%-75.5%, respectively. Phylogenetic analysis revealed that the NM strain was closely related to the reference strains isolated from America, which belong to the A2 type. Notably, there were 5 amino acid insertions in variable region 4 and a highly variable motif at the C-terminal of the surface glycoprotein (SU5). Conclusions: The present study is the first to show the whole-genome sequence of an MVV obtained from China. The detailed analyses provide essential information for understanding the genetic characteristics of MVV, and the results enrich the MVV library.

• The Journal of Korean Society of Virology
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• v.30 no.3
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• pp.211-217
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• 2000

Nef is a lentiviral protein involved in pathogenesis of AIDS, but its molecular mechanism of action remains incompletely understood. Here we report the isolation of the interacting protein with the HIV-1 Nef, using the yeast two hybrid system for expression cloning. One of the positive colonies was selected as the final candidate for the interacting protein gene. The nucleotide sequencing revealed that this interacting protein is Human Ikaros/LyF-1. This protein interacted with the C-terminal region of Nef specifically in yeast system, not with the N-terminal region. This interaction was also confirmed by in vitro binding assay.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.70-75
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• 2008

Two extracellular amylase isozymes were purified and characterized from alkalophilic Pseudomonas sp. KFCC 10818 for the production of maltooligosaccharides. The molecular weights of the homogeneous proteins were 50 kDa and 75 kDa, respectively. The 50 and 75 kDa amylases showed optimum temperatures at 35 and $40^{\circ}C$, respectively. The optimum pH of the enzymes ranged from pH 6-8, and the enzymes were resistant to an alkaline condition of pH 12. Via the enzyme's actions, the final products from maltooligosaccharides or soluble starch were maltose and maltotriose. Calcium was a potent activator of the 50 kDa amylase. Finally, the N-terminal amino acid sequences of the 50 and 75 kDa amylases were QTVPKTTFV and DTVPGNAFQ, respectively.

• BMB Reports
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• v.37 no.2
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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.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.127-145
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• 2011

Various environmental ecosystems are valuable sources for microbial ecology studies, and their analyses using recently developed molecular ecological approaches have drawn significant attention within the scientific community. Changes in the microbial community structures due to various anthropogenic activities can be evaluated by various culture-independent methods e.g. ARISA, DGGE, SSCP, T-RFLP, clone library, pyrosequencing, etc. Direct amplification of total community DNA and amplification of most conserved region (16S rRNA) are common initial steps, followed by either fingerprinting or sequencing analysis. Fingerprinting methods are relatively quicker than sequencing analysis in evaluating the changes in the microbial community. Being an efficient, sensitive and time- and cost effective method, T-RFLP is regularly used by many researchers to access the microbial diversity. Among various fingerprinting methods T-RFLP became an important tool in studying the microbial community structure because of its sensitivity and reproducibility. In this present review, we will discuss the important developments in T-RFLP methodology to distinguish the total microbial diversity and community composition in the various ecosystems.