• BMB Reports
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• v.30 no.1
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• pp.80-84
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• 1997

The synthesis and secretion of human angiogenin in E. coli by the natural leader sequence has been studied. We constructed a recombinant plasmid containing human angiogenin cDNA which encompassed all the coding region including leader sequence required for secretion. The recombinant plasmid was introduced into a suitable E. coli host. The angiogenin was detected in the culture medium and periplasm upon the induction of gene expression. The molecular weight of the secreted angiogenin was identical to that of authentic angiogenin purfied from human plasma when estimated by SDS-PAGE and immunoblotting. showing that the natural leader sequence was recognized and processed by the secretion machinery of E. coli. The angiogenin concentration in the culture medium reached a maximum within 2 h when expressed at $37^{\circ}C$ with 0.02~2 mM IPTG. In contrast, the expression level increased gradually over time up to 11 h at $23^{\circ}C$ with 0.002~2 mM IPTG and at $37^{\circ}C$ with 0.002 mM IPTG.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.903-908
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• 2001

The gene aeg-46.5, which is expressed under anaerobic condition, has putative triple -10 regions and four transcription start sites. The mRNA transcription level and its start point change depending on the aerobic/anaerobic growth condition. RNA polymerase and its regulatory proteins must choose which of three -10 region to use. The putative triple 10 region was mutated to make only one of them function with consensus -10 region sequence (TATAAT) and the other two as non-functional region. The results show that the second and third -10 regions are used for the aerobic/anaerobic expression. The third -10 region is responsible for the high aerobic to anaerobic switch ratio. This suggests that only the last two of the putative triple -10 region have functions on aeg-46.5 gene expression switch control. The phenotype of the mutated promoter was tested in the wild type cell and narL - cell. The results indicate that the control by NarL is independent from the selection of -10 region. The expression patterns on multi-copy plasmids and on single-copy chromosome were compared. These results show that the aerobic/anaerobic switch control of aeg-46.5 is through the choice of -10 region. The mechanism of choosing different -10 region remains to be seen.

• Mycobiology
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• v.47 no.3
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• pp.319-328
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• 2019

Cytospora is a genus including important phytopathogens causing severe dieback and canker diseases distributed worldwide with a wide host range. However, identification of Cytospora species is difficult since the currently available DNA sequence data are insufficient. Aside the limited availability of ex-type sequence data, most of the genetic work is only based on the ITS region DNA marker which lacks the resolution to delineate to the species level in Cytospora. In this study, three fresh strains were isolated from the symptomatic branches of Elaeagnus angustifolia in Xinjiang Uygur Autonomous Region, China. Morphological observation and multi-locus phylogenetic analyses (ITS, LSU, ACT and RPB2) support these specimens are best accommodated as a distinct novel species of Cytospora. Cytospora elaeagnicola sp. nov. is introduced, having discoid, nearly flat, pycnidial conidiomata with hyaline, allantoid conidia, and differs from its relatives genetically and by host association.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.244-250
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• 2000

An ${\alpha}-glucosidase$ gene (aglA) from thermophilic Bacillus sp. DG0303 was cloned, sequenced, and expressed in Escherichia coli. The aglA was localized to the 2.1-kb PvuI-XmnI region within the 5.9-kb DNA insert of the gybrid plasmid pAG1. The gene consisted of an open reading frame of 1,686 bp with an unusual GTG initiation codon and TGA termination codon. The amino acid sequence deduced from the nucleotide sequence predicted a protein of 562 amino acid residues with a M, of 66,551 dalton. A comparative amino acid sequence analysis revealed that DG0303 ${\alpha}-glucosidase$ is related to bacillary oligo-1, 6-glucosidases. The Bacillus sp. DG0303 ${\alpha}-glucosidase$ showed a high sequence identity (36-59%) to the B. flavocaldarius, B. cereus, and B. thermoglucosidasius oligo-1, 6-glucosidases. The number of prolines in theses four ${\alpha}-glucosidases. was observed to increase with increasing thermostability of these enzymes. The cloned ${\alpha}-glucosidase was purified from E. coli $DH5{\alpha}$ bearing pAG1 and characterized. The recombinant enzyme was identical with the native enzyme in its optimum pH and in its molecular mass, estimated by sodium dodecy1 sulfate-polyacrylamide gel electrophoresis. The temperature optimum of the cloned ${\alpha}-glucosidase$ was lower than that of the native enzyme.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.240-246
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• 1998

A cDNA encoding desiccation-related protein was isolated from a flower bud cDNA library of Chinese cabbage (C-DH) and its nucleotide sequence was characterized. It contains 679 bp nucleotides with 501 bp open reading frame. The amino acid sequence of the putative protein showed the highest amino acid sequence homology (79 % identity) to dehydrin protein in Gossypium hirsutum. Also, the C-DH shares 48-52% amino acid sequence identity with the other typical dehydrin proteins in plant cells. When the amino acid sequence of their proteins were aligned, several peptide motifs were well conserved, of which function has to be solved. Particularly the C-DH contains 15 additional amino acids at its N-terminus. Genomic Southern blot analysis using the coding region of C-DH showed that the C-DH consists of a single copy gene in Chinese cabbage genome. The C-DH mRNA, whose transcript size is 0.7 kb, was expressed with a tissue-specific manner. It was highly expressed in seed, flower buds and low expression as detected in root, stem or leaf tissues of Chinese cabbage. And the transcript level of C-DH was significantly induced by the treatment of plant hormone, abscisic acid and water-deficit conditions.

• The Korea Journal of Herbology
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• v.24 no.3
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• pp.59-68
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• 2009

Objectives : Bupleuri Radix (Siho) is prescribed as the root of different Bupleurum species on the pharmarcopoeia in Korea and China. Moreover, other species and varieties of the genus Bupleurum have been also distributed on the herbal market as Bupleuri Radix. However, due to the morphological similarity and frequent occurrence of intermediate forms, the correct identification of this radix is very difficult. To develop a reliable method for correct identification and improving the quality standards of official Bupleuri Radix, we analyzed sequences of the ribosomal RNA gene and internal transcribed spacer (rDNA-ITS) region. Methods : PCR amplification of rDNA-ITS region was performed using ITS1 and ITS4 primer from 6 Bupleurum species and 1 variety, B. falcatum L. (Siho), an improved breed of B. falcatum L. (Samdo-Siho), B. chinense DC. (Buk-Siho), B. scorzonerifolium Willd. (Nam-Siho), B. longiadiatum Turcz. (Gae-Siho), B. euphorbiodes Nakai (Deungdae-Siho) and B. latissimum Nakai (Seom-Siho), and nucleotide sequence was determined after sub-cloning into the pGEM-Teasy vector. Authentic marker nucleotides were estimated by the analysis of ClastalW using entire rDNA-ITS sequence of three samples per species. Results : In comparative analysis of the rDNA-ITS sequences, we found specific nucleotides to distinguish Korean (B. falcatum L. and its variety) and Chinese official species (B. chinense DC. and B. scorzonerifolium Willd.) from others at positions 411 and 447, and positions 89, 101, 415 and 599, respectively. Futhermore, we also found nucleotide indels (insertion and/or deletion) and substitutions to identify each of different Bupleurum species, 2 positions for B. falcatum L. and its variety, 6 positions for B. chinense DC., 49 positions for B. scorzonerifolium Willd., 8 positions for B. euphorbioides Nakai, 7 positions for B. longiradiatum Nakai and 9 positions for B. latissimum Nakai. These sequence differences at corresponding positions are avaliable nucleotide markers to determine the botanical origins of Bupleuri Radix. Moreover, we confirmed the phylogenetic relationship of B. latissimum Nakai, a Korean endemic speices, among Bupleurum species based on the rDNA-ITS sequence. Conclusions : These marker nucleotides would be useful to identify the official herbal medicines by the providing of definitive information that can identify each plant species and distinguish it from unauthentic adulterant Bupleurum species.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.20 no.2
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• pp.187-198
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• 1990

Examinations of the temporomandibular joints were performed on a 1.5 Tesla magnetic resonance (MR) system. An MR surface receiver coil 3 inch in diameter was placed on plastic frame, the patient's head being placed in the frame so that the coil was pressed against the temporal region. In taking advantage of the magnetic resonance imaging that has been studied briskly till now, author obtained the images of parasagittal and paracoronal planes about the temporomandibular joint by using MPGR (Multi-Planar Gradient Recalled), GRASS (Gradient Recalled Acquisition in the Steady State), and CSMEMP (Contiguous Slice Multiple Echo, Multi-Planar), that differ from the Spin Echo pulse sequence which the previous authors used. Five subjects with no symptoms of temporomandibular joint pain and dysfunction were studied. The plane images obtained by these methods were compared with those by Spin Echo pulse sequence. The results were as follows: 1. The optimal repetition times (TR) and echo times (TE) for T.M.J. image were; a. 400 msec and 18 msec in PMGR pulse sequence. b. 40 msec and 12 msec in GRASS pulse sequence. c. 700 msec and 30 msec in CSMEMP pulse sequence. d. 500 msec and 20 msec in Spin Echo pulse sequence. 2. When the MPGR pulse sequence was using, T2-weighted image was obtained in very short time. On the image of the paracoronal plane by GRASS pulse sequence, meniscus showed the moderate signal intensity, and the meniscus and its anteromedial, posterolateral attachments were observed definitely with gray color. 4. The signal intensity of Spin Echo pulse sequence was equal to that of CSMEMP pulse sequence, but the image by CSMEMP pulse sequence showed relatively lower level in its resolution.

• Mycobiology
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• v.35 no.4
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• pp.171-173
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• 2007

Some Xylaria materials growing on the fruits of Liquidambar spp. were collected. They were identified as X. persicaria on the basis of morphological characteristics and sequence analysis of the complete ITS region (ITS1-5.8S-ITS2) of rDNA. This is the first record of this species from Korea.

• Journal of Microbiology
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• v.41 no.2
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• pp.157-160
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• 2003

To estimate genetic relationships within the genus Rhizopus, genetic variations in 20 strains were investigated by DGGE and PCR-RFLP of rDNA ITS region (ITSI, ITS2,5.8S). The size of the amplified products showed the interspecific polymorphisms, 650 bp,700 bp, and 900 bp. The DGGE approach allowed the separation of PCR amplicons of the same length according to their sequence variations. When the rDNA ITS region was digested with six restriction enzymes, 20 strains were classified into five RFLP haplotypes. The range of similarity between the 20 strains by PCR-RFLP was 42.3-100%. Based on the results of DGGE aud PCR-RFLP, the 20 strains were divided into four groups, R. oryzae, R. stolonifer, R. microsporus and R. homothallicus. Further study of R. homothallicus is required.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.1-7
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• 2011

This work was performed to confirm the molecular discrimination through the nrITS1 sequences among 3 taxa of Scirpus L. sensu lato (s.l.) species. S. planiculmis represented only 2 base sequence variations with S. maritimus in spite that they showed different morphological features. The nucleotide sequences of the ITS1 region from S. planiculmis were shown to have 99.1% homology with S. maritimus and 60.4% homology with S. triqueter. Although the morphology of S. planiculmis is similar with S. triqueter, molecular basis of the size and sequences on ITS1 region were shown to have distinctive differences. For divergency investigation on same sites and metapopulation, sequencing was conducted on ITS1 region with partial 5.8S and 18S regions. All plants of each species collected at the same site had identical band size pattern and sequences. Intraspecific molecular divergency was not identified in spite that these species live in different wetland sites. The ITS1 sequences described here provided a powerful genetic tool for phylogenetic studies which was difficult by morphological identification as high rate of morphological plasticity.