• Journal of Microbiology and Biotechnology
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• 제16권1호
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• pp.77-83
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• 2006

A gene encoding a $\gamma-butyrolactone$ autoregulator receptor was cloned from Saccharopolyspora erythraea, and the biochemical characteristics, including the autoregulator specificity, were determined with the purified recombinant protein. Using primers designed for the conserved amino acid sequence of Streptomyces $\gamma-butyrolactone$ autoregulator receptors, a 120 bp S. erythraea DNA fragment was obtained by PCR. Southern and colony hybridization with the 120 bp fragment as a probe allowed to select a genomic clone of S. erythraea, pESG, harboring a 3.2 kb SacI fragment. Nucleotide sequencing analysis revealed a 615 bp open reading frame (ORF), showing moderate homology (identity, $31-34\%$; similarity, $45-47\%$) with the $\gamma-butyrolactone$ autoregulator receptors from Streptomyces sp., and this ORF was named seaR (Saccharopolyspora erythraea autoregulator receptor). The seaR/pET-3d plasmid was constructed to overexpress the recombinant SeaR protein (rSeaR) in Escherichia coli, and the rSeaR protein was purified to homogeneity by DEAE-Sephacel column chromatography, followed by DEAE-ion-exchange HPLC. The molecular mass of the purified rSeaR protein was 52 kDa by HPLC gel-filtration chromatography and 27 kDa by SDS-polyacrylamide gel electrophoresis, indicating that the rSeaR protein is present as a dimer. A binding assay with tritium-labeled autoregulators revealed that rSeaR has clear binding activity with a VB-C-type autoregulator as the most effective ligand, demonstrating for the first time that the erythromycin producer S. erythraea possesses a gene for the $\gamma-butyrolactone$autoregulator receptor.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1189-1196
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• 2005

The cyclohexanol dehydrogenase (ChnA), produced by Rhodococcus sp. TK6, which is capable of growth on cyclohexanol as the sole carbon source, has been previously purified and characterized. However, the current study cloned the complete gene (chnA) for ChnA and its flanking regions using a combination of a polymerase chain reaction (PCR) based on the N-terminal amino acid sequence of the purified ChnA and plaque hybridization from a phage library of Rhodococcus sp. TK6. A sequence analysis of the 5,965-bp DNA fragment revealed five potential open reading frames (ORFs) designated as partial pte (phosphotriesterase), acs (acyl-CoA synthetase), scd (short chain dehydrogenase), stp (sugar transporter), and chnA (cyclohexanol dehydrogenase), respectively. The deduced amino acid sequence of the chnA gene exhibited a similarity of up to $53\%$ with members of the short-chain dehydrogenase/reductase (SDR) family. The chnA gene was expressed using the pET21 a(+) system in Escherichia coli. The activity of the expressed ChnA was then confirmed (13.6 U/mg of protein) and its properties investigated.

• Journal of Microbiology and Biotechnology
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• 제13권6호
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• pp.976-983
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• 2003

Seven Escherichia coli cells defective with aerobic growth were isolated by the insertion of ${\lambda}placMu53$, a hybrid bacteriophage of ${\lambda}$ and Mu, which created a transcriptional fusion to lacZY. These insertion mutant cells were tested on an XG ($5-bromo-4-chloro-3-indolyl-{\beta}-D-galactopyranoside$) medium for anaerobic expression of lacZ by fusion to a promoter. The chromosomal DNA from these strains were digested by EcoRI, and the EcoRI fragments that contained the fused gene and lacZ sequence were identified by Southern hybridization, using lacZ containing plasmid as a probe. The EcoRI fragment from each strain was cloned and sequenced. The sequence data were compared with the GenBank database. The mutated gene of three strains, CYT4, CYT5, and OS11, was found to be identical, and it was nrdAB that encoded ribonucleoside diphosphate reductase. The gene nrdAB was at min 50.5 on the Escherichia coli linkage map and 2,348,084 on the physical map, and is involved in hemAe-related reduction-oxidation reaction. OS6 and OS14 mutant strains had insertion at min 8.3 and the mutated gene was hemB. The hemB encodes 5-aminolevulinate dehydratase or porphobilinogen synthase. The OS3 mutant had insertion in cydB at min 16.6. The cydAB encodes cytochrome d oxidase. In the case of OS1, the fusion was made with sucA, the E1 component of ${\alpha}-ketoglutarate$ dehydrogenase.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.154-161
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• 2007

Human immunodeficiency virus type 1 (HIV-1) infections are responsible for a substantial number of deaths annually and represent a significant threat to public health. According to the latest study, the Tat (Transactivator of transcription) protein is essential in transcription and replication of viral genes, and is among the early expression genes involved in the life cycle of HIV. The virion NC (nucleocapsid) plays an important role in early mRNA expression and contributes to the rapid viral replication that occurs during HIV-1 infection. Therefore, we attempted to elucidate the relationship between the Tat protein and nucleocapsid protein. In a comparison of two independently prepared and hybridized samples, flag NC overexpressed HEK 293T cells and pTat overexpressed HEK 293T cells, and hybridization showed the differences in expression in each case. Among the microarray results confirmed with real-time reverse transcriptase assay, twelve genes were identified to be involved according to their gene expression profiles. Of approximately 8,208 human genes that were analyzed, we monitored candidate genes that might have been related to NC and Tat genes from gene expression profiles. Additionally, the pathways could be viewed and analyzed through the use of Pathway Studio software. The pathways from the gene list were built and paths were found among the molecules/cell objects/processes by the curation method.

• 한국미생물·생명공학회지
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• 제18권6호
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• pp.633-639
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• 1990

Cellulase 복합체와 xylanase를 동시에 분비하는 Pseudomonas sp. LBC 505와 CYC 10의 cellulase 유전자를 pUC19를 사용하여 E.coli에 클로닝시켰다. Congo red 염색시 노란색 환을 형성하는 대장균 형질전환에서 7.0Kb-와 4.6Kb-HindIII 단편을 함유한 재조합 플라스미드 pLC1과 pLC2를 가각 분리하였다. DNA hybridization 실험에서 pLC1 과 pLC2는 Pseudomonas sp. LBC 505와 CYC 10 유래임이 각각 밝혀졌고, Immunoassay 실험에서도 유사성이 인정되었다. pLC1을 함유하고 있는 대장균은 cellulas의 24를 세포외로 분비하였고, 효소활성은 모균주에 비해 1.4배 증가하였다. pLC1과 pLC2의 효소학적 성질도 모균주와 동일하였으며, 기질특이성과 HPLC로 유리당을 분석한 결과, 클로닝된 유전자는 endo type인 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1679-1687
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• 2009

Three parathion-degrading bacteria and eight pairs of bacteria showing syntrophic metabolism of parathion were isolated from rice field soils, and their genetic and phenotypic characteristics were investigated. The three isolates and eight syntrophic pairs were able to utilize parathion as a sole source of carbon and energy, producing p-nitrophenol as the intermediate metabolite during the complete degradation of parathion. Analysis of the 16S rRNA gene sequence indicated that the isolates were related to members of the genera Burkholderia, Arthrobacter, Pseudomonas, Variovorax, and Ensifer. The chromosomal DNA patterns of the isolates obtained by polymerasechain-reaction (PCR) amplification of repetitive extragenic palindromic (REP) sequences were distinct from one another. Ten of the isolates had plasmids. All of the isolates and syntrophic pairs were able to degrade parathion-related compounds such as EPN, p-nitrophenol, fenitrothion, and methyl parathion. When analyzed with PCR amplification and dot-blotting hybridization using various primers targeted for the organophosphorus pesticide hydrolase genes of previously reported isolates, most of the isolates did not show positive signals, suggesting that their parathion hydrolase genes had no significant sequence homology with those of the previously reported organosphophate pesticide-degrading isolates.

• 생명과학회지
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• 제20권2호
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• pp.176-182
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• 2010

벼의 생산에 있어 가장 큰 문제 요인 중 하나인 벼도열병의 발생 원인균인 벼도열병균은 다양한 기작에 의해 방제 약제에 대한 내성을 가지는 것으로 알려져 있다. 막 운반단백질인 ABC transporter의 경우 환경으로부터의 다양한 독성 물질들을 배출하는 것으로 알려져 있다. 이미 알려진 벼도열병균의 게놈 서열로부터 생물정보학적 분석을 통하여 ABC transporter 단백질의 도메인 특성을 보이는 33개의 유전자군 서열을 예측하였다. 이중 3개의 경우는 이미 알려진 유전자로 판명되었다. Southern Hybridization 분석에 적용한 20개의 유전자들이 모두 게놈상에 단일 copy로 존재함을 확인하였다. 새로 예측된 30개의 유전자중 11개는 RT-PCR을 통하여 전사단계에서의 유전자 발현이 확인되었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권5호
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• pp.393-399
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• 2004

Useful genes can be Screened from various environments by construction of metagenomic DNA libraries. In this study, water samples were collected from several lakes in mid Korea, and analyzed by T-RFLP to examine diversities of the microbial communities. The crude DNAs r were extracted by the SDS-based freezing-thawing method, and then further purified using an $UltraClean^{TM}$ kit (MoBio, USA). The metagenomic libraries were constructed with the DNAs partially digested with EcoR I, BamH I, and Sac II in Escherichia coli DH 10B using the pBACe3.6 vector. About 44.0 Mb of metagenomic libraries were obtained with average inserts 13-15 kb in size. The bphC genes responsible for degradation of aromatic hydrocarbons via mets-cleavage were identified from the metagenomic libraries by colony hybridization using the bphC specific sequence as a probe. The 2,3-dihydroxybiphenyl (2, 3-DHBP) dioxygenase gene (bphC ), capable of degradation of 2,3-DHBP, was cloned and its nucleotide Sequences analyzed. The genes consisted of 966 and 897 base pairs with an ATG initiation codon and a TGA termination codon. The activity of the 2,3-DHBP dioxygenase was highly expressed to 2,3-DHBP and Showed a broad substrate range to 2,3-DHBP, catechol, 3-methylcatechol and 4-methylcatechol. These results in-dicated that the bphC gene identified from the metagenomes derived from lake water might be useful in the development of a potent strain for degradation of aromatic pollutants.

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7333-7336
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• 2014

Human papillomavirus (HPV) infection has been implicated as a causative of cervical cancer. In the present study, a total of 578 samples from females attending the gynecological outpatient clinic in Henan province, China, were collected and the HPV genotypes were detected by gene chip and flow-through hybridization. Overall, 44.5% (257/578) females were found to be HPV DNA positive, and the high risk HPV (HR-HPV) rate was 35.1% (203/578). The first peak of HR-HPV infection appeared in the >60 year-old group (55.0%), and the second was within the 51-55 year-old group (50.0%) (${\chi}^2$=19.497, p<0.05). HPV 16 was the most prevalent genotype (9.2%), followed by HPV 52 (7.8%), HPV 6 (6.9%), HPV 11 (5.9%) and HPV 42 (5.0%). The single type HPV infection was 30.4%, with the five majority prevalent genotype HPV 16 (16.5%), HPV 52 (14.3%), HPV 6 (12.6%), HPV 42 (8.6%), HPV 31 (5.1%). The multiple-type HPV infections were 14.0%, and HPV 16 was the most prevalent type (29.6%), followed by HPV 52 (24.7%), HPV 6 (22.2%), HPV 11 (22.2%), HPV 42 (17.3%) and HPV 39 (17.3%).

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1863-1869
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• 2014

The amplification of telomerase component (TERC) gene could play an important role in generation and treatment of haematological malignancies. This present study was aimed to investigate copy number amplification status of TERC gene in chronic myeloid leukaemia (CML) patients who were being treated with imatinib mesylate (IM). Genomic DNA was extracted from peripheral blood of CML-IM Resistant (n=63), CML-IM Respond (n=63) and healthy individuals (n=30). TERC gene copy number predicted (CNP) and copy number calculated (CNC) were determined based on $Taqman^{(R)}$ Copy Number Assay. Fluorescence in situ hybridization (FISH) analysis was performed to confirm the normal signal pattern in C4 (calibrator) for TERC gene. Nine of CML patients showed TERC gene amplification (CNP=3), others had 2 CNP. A total of 17 CML patients expressed CNC>2.31 and the rest had 2.31>CNC>1.5. TERC gene CNP value in healthy individuals was 2 and their CNC value showed in range 1.59-2.31. The average CNC TERC gene copy number was 2.07, 1.99 and 1.94 in CML-IM Resistant patients, CML-IM Respond and healthy groups, respectively. No significant difference of TERC gene amplification observed between CML-IM Resistant and CML-IM Respond patients. Low levels of TERC gene amplification might not have a huge impact in haematological disorders especially in terms of resistance towards IM treatment.