• Korean Journal of Microbiology
• /
• v.46 no.3
• /
• pp.296-302
• /
• 2010

Microcystis (Cyanobacteria, Chroococcales) is one of the green tide-causing organisms in freshwaters, and some species produce microcystin that is hepatotoxin. In the aspects of freshwater quality controls and health concerns, therefore it is necessary to manage the harmful organisms. In the present study, RNA polymerase beta subunit (rpoB) gene sequences of Microcystis were determined and characterized in order to use a potential marker for the molecular detections of the species. Microcystis rpoB showed high divergences of DNA similarity and genetic distances when compared with those of 16S rRNA, and the molecular differences were statistically significant (Student t-test, p<0.05). Parsimony analyses showed the rpoB gene evolves more than 2-fold faster than 16S rRNA. In addition, phylogeny of the rpoB gene separated each M. aeruginosa strain more clearly compared with a 16S rRNA tree. This study found that the order Chroococcales, including Microcystis, has approximately two rRNA operons and single copy of the rpoB gene in their chromosomes. These results suggest that the rpoB gene is a useful marker for the molecular phylogenetics and the detection of Microcystis.

• Environmental Mutagens and Carcinogens
• /
• v.22 no.4
• /
• pp.223-228
• /
• 2002

Hypertension is characterized by multiple genetic and environmental factors. To establish the genetic basis of hypertension in Koreans, we investigated the genetic variations of two candidate genes (aldosterone synthase (CYP11B2), ${\gamma}$ subunit of the amiloride-sensitive epithelial sodium channel (ENaC) in the Korean patients with hypertension and normotensive controls. There were no significant differences in the genotype and allele frequencies between two groups, respectively. However, there was the significant difference between Korean and Caucasian populations in allele frequency of RFLPs in the two candidate genes. Therefore, these studies also need to be confirmed in other ethnic groups, although our results do not support a possible role of these genes on hypertension in Korean population

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.4
• /
• pp.1005-1009
• /
• 2013

Using DNA sequencing method, we analyzed mutations of rpoB (RNA polymerase beta subunit) rifampin-resistant Mycobaterium tuberculosis strains which were identified by conventional test at Masan National Hospital and The Korean Institute of Tuberculosis. Though it has been reported different mutations of rpoB region of rifampin-resistant M. tuberculosis strains in the south of Korea, it is not confirmed whether these mutations of rpoB region actually express rifampin resistance through experiment. We confirmed experimentally these mutations of rpoB region of M. tuberculosis strains induced rifampin-resistance through ampified rpoB by polymerase chain reaction (PCR) and cloning of mutant rpoB into rifampin sensitive-M. tuberculosis strain.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.3
• /
• pp.542-549
• /
• 2010

In the present study, overexpression, purification, and characterization of Aeropyrum pernix K1 chaperonin B in E. coli were investigated. The chaperonin $\beta$-subunit gene (ApCpnB, 1,665 bp ORF) from the hyperthermophilic archaeon A. pernix K1 was amplified by PCR and subcloned into vector pET21a. The constructed pET21a-ApCpnB (6.9 kb) was transformed into E. coli BL21 Codonplus (DE3). The transformant cell successfully expressed ApCpnB, and the expression of ApCpnB (61.2 kDa) was identified through analysis of the fractions by SDS-PAGE (14% gel). The recombinant ApCpnB was purified to higher than 94% by using heat-shock treatment at $90^{\circ}C$ for 20 min and fast protein liquid chromatography on a HiTrap Q column step. The purified ApCpnB showed ATPase activity and its activity was dependent on temperature. In the presence of ATP, ApCpnB effectively protected citrate synthase (CS) and alcohol dehydrogenase (ADH) from thermal aggregation and inactivation at $43^{\circ}$ and $50^{\circ}$, respectively. Specifically, the activity of malate dehydrogenase (MDH) at $85^{\circ}$ was greatly stabilized by the addition of ApCpnB and ATP. Coexpression of pro-carboxypeptidase B (pro-CPB) and ApCpnB in E. coli BL21 Codonplus (DE3) had a marked effect on the yield of pro-CPB as a soluble and active form, speculating that ApCpnB facilitates the correct folding of pro-CPB. These results suggest that ApCpnB has both foldase and holdase activities and can be used as a powerful molecular machinery for the production of recombinant proteins as soluble and active forms in E. coli.

• The Korean Journal of Mycology
• /
• v.49 no.3
• /
• pp.315-324
• /
• 2021

In this study, the fungal strains KNU-Gunwi 2B and KNU-SOT5 were isolated from root-soil in a hillside and the cherry tree bark (Prunus serrulata), respectively from Gyeongbuk province in Korea. The strain KNU-SOT5 produced dark brown chlamydospores that were smooth to lightly rough-walled, globose to ellipsoidal, and the conidia were aseptate, guttulate, mostly fusiform with a diameter of 5.3-17.6×4.2-7.0 ㎛. Strain KNU-Gunwi 2B produced phialides that were smooth-walled, cylindrical with semi-papillate apices and the conidia were pale-green, broadly ellipsoid, and sometimes cylindrical with a diameter of 4.4-8.0×2.3-4.0 ㎛. The strain KNU-SOT5 and KNU-Gunwi 2B were resolved based on cultural and morphological characteristics, along with the phylogenetic analysis using the small subunit (SSU), large subunit (LSU), and internal transcribed spacers (ITS) regions. The fungal strains KNU-SOT5 and KNU-Gunwi 2B were identified as Dothidea insculpta and Metarhizium rileyi, which have not been reported in Korea.

• Journal of Food Hygiene and Safety
• /
• v.39 no.3
• /
• pp.209-220
• /
• 2024

Cavier is graded as Beluga, Osetra, and Sevruga based on the species of sturgeon (Acipenser sinensis). In this study, we developed an analytical method for determining the grade of black caviar using DNA barcodes and KASP markers. To identify the sturgeon species, ten black caviar samples were collected, and a reference DNA barcode library was developed using five genes (namely, 16S ribosomal RNA, cytochrome b, cytochrome c oxidase subunit I, cytochrome c oxidase subunit II, and NADH dehydrogenase subunit 5 genes). To develop the KASP markers, we selected 11 markers that could distinguish between the five grades of black caviar. As a result, specific markers for each of the targeted caviars were clustered into FAM-positive sections. DNA barcoding and the KASP assay revealed that one Beluga, six Osetra, and three Sevruga were identified among the ten caviar samples. Moreover, we found that the sturgeon species were mislabeled in two products. Here, we aimed to develop a KASP assay based on SNP that allows rapid and easy identification of caviar grade. These methods are expected to contribute to preventing the distribution of illegal products.

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.617-618
• /
• 2005

• Microbiology and Biotechnology Letters
• /
• v.35 no.2
• /
• pp.104-111
• /
• 2007

In this study, aniline dioxygenase genes responsible for initial catabolism of aniline in Burkholderia sp. HY1 and Delftia sp. HY99 were cloned and the amino acid sequences were comparatively analyzed, which already have been reported as bacteria utilizing aniline as a sole source of carbon and nitrogen, B. sp. HY1 was found to have at least a plasmid, and the plasmld-cured strain, B. sp. HY1-PC obtained using mitomycin C was tested with wild type strain to investigate whether the former maintained the degradability for aniline. This proved that the aniline oxygenase gene from B. sp. HY1 was located in chromosomal DNA, not in plasmid DNA. Aniline dioxygenase small subunits from B. sp. HY1 and D. sp. HY99 were found, based on 146 amino acids, to share 79% similarity. Notably, ado2 genes from B. sp. HY1 and D. sp. HY99 which were found to be terminal dioxygenase of aniline dioxygenase small subunit showed 99% similarity in the deduced amino acid sequences with tdnA2 of Frateuria sp. ANA-18 and danA2 of D. sp. AN3, respectively. Besides, enzyme assay and amino acid sequence analysis of catechol dioxygenase supported the previous report that B. sp. HY1 might occupy ortho-cleavage pathway using catechol 1,2-dioxygenase, while D. sp. HY99 might occupy catechol 2,3-dioxygenase for meta-cleavage pathway.

• Journal of Korean Medicine Rehabilitation
• /
• v.20 no.1
• /
• pp.27-36
• /
• 2010

Objectives : We investigated the role of intracellular calcium chelator, bis-(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid(BAPTA), on the modulation of phosphorylation of the spinal N-methyl-D-aspartate receptor(NMDAR) NR1 and NR2B subunits following electroacupuncture(EA). Methods : Bilateral 2 Hz EA stimulation with 1.0 mA was delivered at those acupoints corresponding to Zusanli(ST36) and Sanyinjiao(SP6) in man via needles for 30min. Results : EA analgesia was reduced by intra-peritoneal injection at a higher dose of BAPTA from termination of EA stimulation. At 60 min after EA treatment, the total number of c-fos-immunostained neurons in each regions of the dorsal horn in the $L_{4-5}$ segments was decreased by BAPTA injection, especially in nucleus proprius. The mean integrated optical density (IOD) of NR1 and NR2B subunits were increased only in superficial laminae of EA-treated rats when compared with normal rats. However, the mean IOD of pNR1 was significantly decreased by BAPTA injection in both the superficial laminae and neck region and pNR2B in the superficial laminae. Western blot analyses confirmed the decreased expression of pNR1 and pNR2B. Conclusions : We concluded that intracellular calcium may well play an important role in EA analgesia by modulating the phosphorylation state of spinal NMDAR subunits.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 1998.10a
• /
• pp.8-13
• /
• 1998

Polyoma Virus Enhancer core Binding Protein (PEBP2)는 유전자의 전사를 조절하는 hetero-dimeric transcription factor로서 $\alpha$와 $\beta$ subunit으로 구성되어 있다. $\alpha$ subunit을 coding 하는 유전자중 하나인 PEBP2aB는 급성백혈병과 관련되어있는 t(8;21) 또는 t(12;21)에 의하여 변형됨으로서 백혈병 발병의 원인이 되고 있다 (Miyoshi et al., 1993; .Romana et al., 1995). $\beta$ subunit을 coding 하는 PEBP2$\beta$도 inv(16)에 의하여 변형됨으로서 백혈병을 유도하는 주요 원인이 되고 있다 (Liu et al., 1993). 이 유전자들의 생물학적 활성을 밝히기 위한 연구가 gene targeting에 의한 knockout mouse 생산 방법으로 수행되었다. 그 결과 PEBP2$\alpha$B와 PEBP2$\beta$ 유전자가 definitive hematopoiesis에 있어서 결정적으로 중요한 역할을 하고 있음이 관찰되었다 (Okuda et al., 1996, Wang et al., 1996a, 1996b), 이는 이들 유전자가 bematopoietic master switch 유전자임을 밝힌 중요한 결과로서 이로부터 혈액학 연구 분야의 새로운 장이 열리게 되었다. 또한 이러한 연구 결과들은 PEBP2 family에 속하는 다른 유전자의 생물학적 활성의 연구를 촉진하는 계기가 되었다. 최근 PEBP2$\alpha$A 유전자가 결손된 마우스가 생산되었는데 이 유전자의 경우에는 모든 종류의 뼈의 생성이 완전히 결손됨이 관찰되었다 (Komori et al., 1997). 이는 PEBP2$\alpha$A 유전자가 뼈의 생성을 지배하는 master switch 유전자임을 보여주는 중요한 관찰로서 bone biologist 들의 큰 관심을 모으고 있다. 본 연구팀은 PEBP2 family 유전자 중 유일하게 아직 생물학적 활성이 규명되지 않은 PEBP2$\alpha$C 유전자의 활성을 knockout 마우스를 생산하는 방법에 의하여 분석하였으며 소화기관의 형성에 중요한 역할을 하고 있음을 확인하였다.