• Microbiology and Biotechnology Letters
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• v.34 no.1
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• pp.15-22
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• 2006

A 4,971 bp chromosomal DNA fragment containing the pqrA, paraquat resistance gene, was cloned from Ochrobactrum anthropi JW-2, and the complete nucleotide sequence was determined. Nucleotide and deduced amino acid sequences of the fragment revealed the presence of 4 complete ORFs (orf2, pqrA, orf3, orf4) and two incomplete ORFs(orf1, orf5). Orf1, pqrA, orf4 and orf5 exists at the direct strand but orf2 and orf3 exists at the reverse complementary strand. Orf1 which of incomplete sequences without start codon shares homology with ATP binding region of the response regulator receiver. Orf2 shares high homology with members of the tetR family of transcriptional repressor which have a helix-turn-helix (H-T-H) motif. Therefore, the orf2 is predicted as a transcriptional repressor of pqrA and is designated as pqrR2. Orf3 shares high homology with the members of the lysR family acting as a transcriptional activator which have both of a H-T-H motif at the N-terminal region and substrate binding domain at the C-terminal region. Therefore, the orf3 is predicted as a transcriptional activator of pqrA and is designated as pqrR1. Orf4 shows homology with the periplasmic substrate-binding protein of amino acid ABC transporter. Orf5 which of incomplete sequences without stop codon revealed the homology with the permeases protein of amino acid ABC transporter.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.37-41
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• 2001

Two linear plasmid-like DNAs, 10.2 kb and 7.2 kb were found in the mitochondria of P. ostreatus. They have covalently linked 5'-terminal proteins in both ends. Two continuous fragments of 4.7 kb and 2.3 kb from 7.2 kb DNA were cloned and sequenced. Two long open reading frames (ORF1; 2982 bp, 993 a.a and ORF2; 2703 bp, 900 a.a) and one short open reading frame(ORF3; 771 bp, 256 a.a) were found in the 7.2 kb plasmid. The putative ORF1 and ORF2 have conserved motifs of DNA polymerases and RNA polymerases, respectively, while the ORF3 has homologous regions with phosphatase from Plasmodium, and also with adhesine from Mycoplasma.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.260-266
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• 2002

In this study, chromosomal DNA fragment related to the regulation of phenol metabolism in Ralstonia eutropha JMP 134 was cloned and sequenced. The result has shown that two open reading frames (ORF1 and ORF2) exist on this regulatory region. ORF1, which initiates from 454 bp downstream of the stop codon of the phenol hydroxylase genes, was found to be composed of 501 amino acids. ORF2, whose start codon is overlapped with the stop codon of ORFl, was found to contain 232 amino acids. The comparison of amino acid sequences with other proteins has revealed that ORF1 belongs to the family of NtrC transcriptional activator, whereas ORF2 shares high homology with the family of GntR protein, which is known to be a negative regulator. ORF1 and ORF2 were designated as a putative positive regulator, phlR2 and a negative regulator phlA, respectively. Possible regulatory mechanisms of phenol metabolism in this strain was discussed.

• Korean Journal of Plant Resources
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• v.16 no.1
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• pp.82-88
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• 2003

Genomic RNA sequence of a tobamovirus infecting Eutrema wasabi plant(TMV-W) was determined. The RNA is composed 6,298 nucleotide and contains four OREs encoding the protein of 180KD(OREI), 130KD(ORE2),30KD(ORF3) and 18KD(coat protein, ORF4). ORE4, ORF 3, ORF 2 and ORF 1 are overlaped by 130, 20 and 40 nucleotides, and the overapping region can be folded into a stable hairpin styucture. This includes the 3'non-coding region of 238 nucleotides, coat protein gene(537 nucleotides,179 amino acid), 30KD movement protein gene(825 nucleotides, 275 amino acid), 13(IKD protein gene(1,896 nucleotides, 632 amino acid) and 180KD protein gene(2,958 nucleotides, 986 amino acid). The genomic RNA sequence was compared with homologous regions of eleven other tobamoviruses. TMV-WTE was similar to TMV-WSF(98.6%) in nucleotide sequence.

• Korean Journal of Microbiology
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• v.41 no.4
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• pp.255-261
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• 2005

A 6.7kb DNA fragment containing the sprT gene encoding Streptomyces griseus trypsin (SGT) was cloned from Streptomyces griseus ATCC 10137, and the complete nucleotide sequence was determined. Nucleotide sequence and deduced amino acid or the EcoRI-HindIII fragment revealed the presence or the six complete ORFs containing the sprT gene and one incomplete ORF, which were named ORF1, SGT, ORF2, ORF3, ORF4, ORF5, and ORF6, respectively. ORF1 has homology with the oxidoreductases from several organisms. ORF2 and ORF3 show similarity with unknown proteins and transcription regulator that belongs to the ArsR family, respectively. ORF4 and ORF5 show homology with the peptidoglycan bound protein with LPXTG motif from Listeria monocytogenes and the membrane protein with transmembrane helix from several organisms, respectively. The last ORF, ORF6, shows homology with the lipoprotein from Streptomyces avermitilis.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.105-111
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• 2009

Norovirus (NV) with a variety of genotypes, a member of the family Caliciviridae, causes acute nonbacterial gastroenteritis in humans. We determined the nucleotide sequence of three open reading frames (ORFs) of a NV Korean strain and characterized the genetic relationship with others. The Korean strain designated Hu/NLV/Gunpo/2006/KO was isolated from the stool specimen of a 2-year-old female suffering from gastroenteritis. By performing reverse transcription and PCR amplification, three overlapping cDNAs were synthesized and used for direct sequencing. We found that like other NVs, this strain contains three ORFs: ORF1, 5,100 bp; ORF2, 1,647 bp; ORF3, 765 bp. Of 35 NVs, ORF1 had a level of genetic diversity lower than ORF2 and ORF3, of which the C-termini of the ORF2 and ORF3 showed a relatively high degree of genetic diversity. Phylogenetic analyses indicated that the Korean strain belonged to genogroup II, with Saitama U1, Gifu'96, Mc37, and Vietnam 026 being formed a single genetic cluster. The nucleotide sequence information of three ORFs of a NV Korean isolate will be useful not only for the development of a diagnostic tool and understanding of genetic relationship, but also provide important basic information for the functional analysis of their gene products.

• Journal of Microbiology and Biotechnology
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• v.18 no.6
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• pp.1033-1039
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• 2008

A 3-kb HindIII fragment bearing the cry6Aa2 gene and the adjacent and intergenic regions was cloned from Bacillus thuringiensis strain YBT-1518. Two open reading frames (ORFs), namely, orf1 (termed cry6Aa2) and orf2 that were separated by an inverted-repeat sequence were identified. orf1 encoded a 54-kDa protein that exhibited high toxicity to the plant-parasitic nematode Meloidogyne hapla. The orf2 expression product was not detected by SDS-PAGE, but its mRNA was detected by RT-PCR. The orf2 coexpressed with orf1 at a high level in the absence of the inverted-repeat sequence, whereas, the expression level of otfl was decreased. When orf2 was mutated, the level of orf1 expression was enhanced obviously. In conclusion, the inverted-repeat sequence disturbs orf2 expression, and the orf2 downregulates orf1 expression. This is an example of novel negative regulation in B. thuringiensis and a potential method for enhancing the expression level of cry genes.

• Microbiology and Biotechnology Letters
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• v.43 no.1
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• pp.1-8
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• 2015

In this study, a DNA-launched reverse genetics system was developed from a type 2 porcine reproductive and respiratory syndrome virus (PRRSV) strain, KNU-12. The complete genome of 15,412 nucleotides was assembled as a single cDNA clone and placed under the eukaryotic CMV promoter. Upon transfection of BHK-tailless pCD163 cells with a full-length cDNA clone, viable and infectious type 2 progeny PRRSV were rescued. The reconstituted virus was found to maintain growth properties similar to those of the parental virus in porcine alveolar macrophage (PAM) cells. With the availability of this type 2 PRRSV infectious clone, we first explored the biological relevance of ORF5a in the PRRSV replication cycle. Therefore, we used a PRRSV reverse genetics system to generate an ORF5a knockout mutant clone by changing the ORF5a translation start codon and introducing a stop codon at the 7^th codon of ORF5a. The ORF5a knockout mutant was found to exhibit a lack of infectivity in both BHK-tailless pCD163 and PAM-pCD163 cells, suggesting that inactivation of ORF5a expression is lethal for infectious virus production. In order to restore the ORF5a gene-deleted PRRSV, complementing cell lines were established to stably express the ORF5a protein of PRRSV. ORF5a-expressing cells were capable of supporting the production of the replicationdefective virus, indicating complementation of the impaired ORF5a gene function of PRRSV in trans.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.415-422
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• 1996

A gene coding for a pyruvyl transferase enzyme involved in exopolysaccharide biosynthesis of Zoogloea ramigera 115SLR was isolated and sequenced. A 4.5 kb of BamHI DNA fragment was isolated from chromosomal DNA using a probe derived from ketal pyruvyl transferase gene of Xanthomonas campestris. The nucleotide sequence of 2.66 kb Pst1/HindIII DNA fragment which was homology with a probe revealed the existence of two complete open reading frames (ORF2 and ORF3) and two partial open reading frames (ORFI and ORF4). The deduced amino acid sequence of ORF3 was homologous to the ketalase (GumL product) of X campestris with 49.5% of similarity and 21.6% of identity. ORF2 on the other hand showed the higher identity with the ketalase (ExoV product) of Rhizobium meliloti (36%) as well as the ketalase of X campestris (23%) than that of ORF3. A gene product of ORF2 was determined with a bacteriophage T7 RNA polymerase/promoter system in E. coli. The molecular weight of protein was 33,500 dalton.

• ALGAE
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• v.18 no.3
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• pp.183-190
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• 2003

Except for a group I intron in trnL-uaa occuring in eubacteria and plastids, group I introns are rarely documented in plastid genomes. Here, we report that a green alga, Caulerpa sertularioides, contains three group IA3 introns in the 16S gene (cpSSU), CS-cpSSU.i1, CS-cpSSU.i2 and CS-cpSSU.i3. Each intron has an open reading frame with LAGLIDADG motifs. CS-cpSSU.i1orf and CS-cpSSU.i3orf occur at Loop 6 in the intron secondary structure and CScpSSU. i2orf at Loop 8. CS-cpSSU.i1orf and CS-cpSSU.i2orf contain both LAGLI-DADG motifs but CS-cpSSU.i3orf has only one. CS-cpSSU.i1 and CS-cpSSU.i2 share the insetion sites and the ORFs at Loop 6 and 8 with CpSSU·1 and CpSSU·2 introns of Chlamydomonas pallidostigmatica (Chlorophyceae). In contrast, CS-cpSSU.i3, containing 28 copies of GAAATAT at Loop 6, is a novel intron found only in Caulerpa sertularioides. Possible scenarios of the evolution of the three introns and their possible use in systematic research are discussed.