• Korean Journal of Microbiology
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• v.40 no.2
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• pp.104-110
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• 2004

To determine evolution and genotype of new chromosomal AmpC $\beta$-lactamases among clinical isolates of Enterobacter species, we performed antibiotic susceptibility testing, pI determination, sequencing, and phy-logenetic analysis using developed expression/secretion vector. Six isolates have shown to produce AmpC $\beta$-lactamases. Six genes of AmpC $\beta$-lactamases that are responsible for the resistance to cephamycins (cefoxitin and cefotetan), amoxicillin, cephalothin, and amoxicillin-clavulanic acid were cloned and characterized in pMSG12119. Insert fragment containing the ampC genes was sequenced and found to have an open reading frame coding for 381-amino-acid $\beta$-lactamase. The nucleotide sequence of four ampC genes ($bla_EcloK992004.l$, $bla_EcloK995120.1$, $bla_EcloK99230$, and $bla_EareK9911729$) shared considerable homology with that of chromosomal ampC gene ($bla_EcloMHN1$) of E. cloacae MHN1 (more than 99.6% identity). The sequences of two ampC genes ($bla_EcloK9973$ and $bla_EcloK9914325$) showed close similarity to the chromosomal ampC gene ($bla_EcloQ908R$) of E. clo-acae 908R (99.7% identity). The results from phylogenetic analysis suggested that six ampC genes could be originated from $bla_EcloMHN1$ / or $bla_EcloQ908R$ / MIC patterns and exact pI values of six transformants indicated that the developed expression/secretion vector (pMSG1219) was suitable for the characterization of foreign genes in E. coli strain.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.396-403
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• 2014

Ginseng (Panax ginseng C. A. Meyer) is an economically valuable pharmaceutical crop in Korea. In order to find promising biocontrol agents for soil-borne fungal pathogens which infect ginseng roots, we have isolated actinomycete, BK185 from soil. The isolate was investigated for the antifungal activity against to ginseng rot pathogens prior to testing genetic and chemical properties. The strain was identified as Streptomyces sp. using phylogenetic analysis based on 16S rRNA gene sequence. The most closely related species was S. sporoclivatus and S. geldanamycininus with high similarities (>99%). The isolate, BK185 showed positive reaction for PCR detection targeting biosynthetic gene clusters of PKS (Type-I polyketide synthase) and NRPS (Non-ribosomal polypeptide synthetase) genes. Major metabolite from the BK185 was analyzed by The LC/MS and identified to geldamycin, which was known to contained broad antibacterial, antifungal or anticancer activities. The results provide evidences that the strain, BK185 can be promising biocontrol agent for ginseng organic farming.

• Research in Plant Disease
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• v.22 no.1
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• pp.32-37
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• 2016

In this work, major outer capsid protein (P10) encoded by genome segment S10 of Rice black-streaked dwarf virus (RBSDV) was expressed in Escherichia coli. Genomic dsRNA was extracted from RBSDV-miryang isolate infected rice plants. Based on the sequence of S10 (RBSDV-miryang, GenBank JX994211), a pair of S10 specific primers were designed and used to amplify the fragment encoding the N-part of P10. We amplified the partial gene (S10 1-834 nt) of RBSDV P10 (1-278 aa) by RT-PCR. Amplified RBSDV S10 (1-834 nt) was cloned into the expression vector pET32a (+). Recombinant RBSDV S10 (1-834 nt) was expressed in E. coli BL21(DE3) and purified by nickel-nitrilotriacetic acid (Ni-NTA) affinity column. We successfully obtained P10 partial protein of RBSDV and the purified protein was used to immunize rabbits. The resulting polyclonal antiserum specifically recognized RBSDV from infected plant in both Western blotting and enzyme-linked immunosorbent assay. In this study, we provide purified RBSDV P10 (1-278 aa), which would be good material for the serological study of RBSDV-miryang isolates.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.3
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• pp.101-109
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• 2015

Classic galactosemia (OMIM #230400) is an autosomal recessive inherited metaboic disorder caused by a deficiency of the galactose-1-phosphate uridyltransferase (GALT, EC2.7.7.12) due to mutations in the GALT gene. If untreated, classic galactosemia is a potentially lethal disease presenting with poor feeding, vomiting, jaundice, liver failure, increased bleeding tendency, and septicemia leading to death within a few days after birth. Since 2006, expansion of newborn screening has been enabled the early diagnosis and early intervention of classic galactosemia in Korea. However, newborn screening, followup testing for confirmatory diagnosis and intervention for galactosemia continue to present challenges. In Korea, the prevalence of the classic galactosemia is considered relatively low compared to that of western countries. And the genotype is also clearly different from those of other population. Therefore, our own guideline for confirmatory diagnosis and intervention is needed. Here, the diagnostic algorithm for galactosemia after positive newborn screening result in Korea has been proposed. Considering the low prevalence and different mutation spectrum in Koreans, the early mutation analysis of GALT gene could be a useful tool for the accurate diagnosis and making any treatment decision.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.1
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• pp.40-43
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• 2015

Short-chain acyl-CoA dehydrogenase (SCAD) deficiency is an autosomal recessive mitochondrial disorder of fatty acid oxidation associated with mutations in the ACADS gene. While patients diagnosed clinically have a variable clinical presentation, patients diagnosed by newborn screening are largely asymptomatic. We describe here the case of a 1-year-old male patient who was detected by newborn screening and diagnosed as SCAD deficiency. Spectrometric screening for inborn errors of metabolism at 72hrs after birth showed elevated butyrylcarnitine (C4) level of 1.69 mol/L (normal, <0.83 mol/L), C4/C2 ration of 0.26 (normal, <0.09), C5DC+C60H level of 39 mol/L (normal, <0.28 mol/L), and C5DC/C8 ration of 7.36 (normal, <4.45). The follow-up testing at 18 days of age were performed: liquid chromatography tandem mass spectrometry (LC-MS/MS), urine organic acids, and quantitative acylcarnitine profile. C4 carnitine was elevated as 0.91; urine organic acid analysis showed elevated ethylmalonic acid as 62.87 nmol/molCr (normal, <6.5), methylsuccinate 6.81 nmol/molCr (normal, not detected). Sequence analysis of ACADS revealed a homozygous missense mutation, c.164C>T (p.Pro55Leu). He is growing well and no episodes of seizures or growth retardation had occurred.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2999-3005
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• 2009

Among the more than 120 different types of human papillomavirus (HPV), types 16 and 18 have been known to be high risk agents that cause cervical cancer. We examined, in an immuno-chromatographic analysis, the potential of using the early gene product, E7 protein, as a diagnostic marker of cervical cancer caused by HPV. We developed monoclonal antibodies specific to HPV-16 and 18 E7 proteins that were produced from bacterial cells using gene recombinant technology. For each E7 protein, the optimal antibody pair was selected using the immuno-chromatographic sandwichtype binding system based on the lateral flow through membrane pores. Under these conditions, this rapid testing assay had a detection capability as low as 2 ng/mL of E7 protein. Furthermore, since viral analysis required the host cell to be lysed using chemicals such as detergents, it was possible that the E7 protein was structurally damaged during this process, which would result in a decrease in detection sensitivity. Therefore, we examined the detrimental effects caused by different detergents on the E7 protein using HeLa cells as the host. In these experiments, we found that the damage caused by the detergent, nonylphenylpolyethylene glycol (NP-40), was minimal relative to Triton X-100 commonly used for the cell lysis. Temperature also affected the stability of the E7 protein, and we found that the E7 protein was stabilized at 4$^{\circ}C$ for about 2 h, which was 4 times longer than at room temperature. Finally, a HPV-infected cervical cancer cell line, which was used as a real sample model, was treated using the optimized conditions and the presence of E7 proteins were analyzed by immuno-chromatography. The results of this experiment demonstrated that this rapid test could specifically detect HPV-infected samples.

• Molecules and Cells
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• v.27 no.2
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• pp.175-181
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• 2009

The myosin light chain kinase (MYLK) gene encodes both smooth muscle and nonmuscle cell isoforms. Recently, polymorphisms in MYLK have been reported to be associated with several diseases. To examine the genetic effects of polymorphisms on the risk of asthma and related phenotypes, we scrutinized MYLK by re-sequencing/genotyping and statistical analysis in Korean population (n = 1,015). Seventeen common polymorphisms located in or near exons, having pairwise $r^2$ values less than 0.25, were genotyped. Our statistical analysis did not replicate the associations with the risk of asthma and log-transformed total IgE levels observed among African descendant populations. However, two SNPs in intron 16 (+89872C> G and +92263T> C), which were in tight LD (|D'| = 0.99), revealed significant association with log-transformed blood eosinophil level even after correction multiple testing ($P=0.002/P^{corr}=0.01$ and $P=0.002/P^{corr}=0.01$, respectively). The log-transformed blood eosinophil levels were higher in individuals bearing the minor alleles for +89872C> G and +92263T> C than in those bearing other allele. In additional subgroup analysis, the genetic effects of both SNPs were much more apparent among asthmatic patients and atopic asthma patients. Among atopic asthma patients, the log-transformed blood eosinophil levels were proportionally increased by gene-dose dependent manner of in both +89872C> G and +92263T> C(P = 0.0002 and P = 0.00007, respectively). These findings suggest that MYLK polymorphisms might be among the genetic factors underlying differential increases of blood eosinophil levels among asthmatic patients. Further biological and/or functional studies are needed to confirm our results.

• Journal of Audiology & Otology
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• v.23 no.1
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• pp.20-26
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• 2019

Background and Objectives: Autosomal recessive non-syndromic hearing loss (ARNSHL) with genetic origin is common (1/2000 births). ARNSHL can be associated with mutations in gap junction protein beta 2 (GJB2). To this end, this cohort investigation aimed to find the contribution of GJB2 gene mutations with the genotype-phenotype correlations in 45 ARNSHL cases in the Kurdish population. Subjects and Methods: Genomic DNA was extracted from a total of 45 ARNSHL families. The linkage analysis with 3 short tandem repeat markers linked to GJB2 was performed on 45 ARNSHL families. Only 9 of these families were linked to the DFNB1 locus. All the 45 families who took part were sequenced for confirmation linkage analysis (to perform a large project). Results: A total of three different mutations were determined. Two of which [c.35delG and c.-23+1G>A (IVS1+1G>A)] were previously reported but (c.299-300delAT) mutation was novel in the Kurdish population. The homozygous pathogenic mutations of GJB2 gene was observed in nine out of the 45 families (20%), also heterozygous genotype (c.35delG/N)+(c.-23+1G>A/c.-23+1G>A) were observed in 4/45 families (8.8%). The degree of hearing loss (HL) in patients with other mutations was less severe than patients with c.35delG homozygous mutation (p<0.001). Conclusions: Our data suggest that GJB2 mutations constitute 20% of the etiology of ARNSHL in Iran; moreover, the c.35delG mutation is the most common HL cause in the Kurdish population. Therefore, these mutations should be included in the molecular testing of HL in this population.

• Korean Journal of Audiology
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• v.23 no.1
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• pp.20-26
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• 2019

Background and Objectives: Autosomal recessive non-syndromic hearing loss (ARNSHL) with genetic origin is common (1/2000 births). ARNSHL can be associated with mutations in gap junction protein beta 2 (GJB2). To this end, this cohort investigation aimed to find the contribution of GJB2 gene mutations with the genotype-phenotype correlations in 45 ARNSHL cases in the Kurdish population. Subjects and Methods: Genomic DNA was extracted from a total of 45 ARNSHL families. The linkage analysis with 3 short tandem repeat markers linked to GJB2 was performed on 45 ARNSHL families. Only 9 of these families were linked to the DFNB1 locus. All the 45 families who took part were sequenced for confirmation linkage analysis (to perform a large project). Results: A total of three different mutations were determined. Two of which [c.35delG and c.-23+1G>A (IVS1+1G>A)] were previously reported but (c.299-300delAT) mutation was novel in the Kurdish population. The homozygous pathogenic mutations of GJB2 gene was observed in nine out of the 45 families (20%), also heterozygous genotype (c.35delG/N)+(c.-23+1G>A/c.-23+1G>A) were observed in 4/45 families (8.8%). The degree of hearing loss (HL) in patients with other mutations was less severe than patients with c.35delG homozygous mutation (p<0.001). Conclusions: Our data suggest that GJB2 mutations constitute 20% of the etiology of ARNSHL in Iran; moreover, the c.35delG mutation is the most common HL cause in the Kurdish population. Therefore, these mutations should be included in the molecular testing of HL in this population.

• Korean Journal of Schizophrenia Research
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• v.21 no.2
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• pp.43-50
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• 2018

Objectives : Genome-wide association studies (GWASs) and meta-analyses indicate that single-nucleotide polymorphisms (SNPs) in the a-1C subunit of the L-type voltage-dependent calcium channel (CACNA1C) gene increase the risk for schizophrenia and bipolar disorders (BDs). We investigated the association between the genetic variants on CACNA1C and schizophrenia and/or BDs in the Korean population. Methods : A total of 582 patients with schizophrenia, 336 patients with BDs consisting of 179 bipolar I disorder (BD-I) and 157 bipolar II disorder (BD-II), and 502 healthy controls were recruited. Based on previous results from other populations, three SNPs (rs10848635, rs1006737, and rs4765905) were selected and genotype-wise association was evaluated using logistic regression analysis under additive, dominant and recessive genetic models. Results : rs10848635 showed a significant association with schizophrenia (p=0.010), the combined schizophrenia and BD group (p=0.018), and the combined schizophrenia and BD-I group (p=0.011). The best fit model was dominant model for all of these phenotypes. The association remained significant after correction for multiple testing in schizophrenia and the combined schizophrenia and BD-I group. Conclusion : We identified a possible role of CACNA1C in the common susceptibility of schizophrenia and BD-I. However no association trend was observed for BD-II. Further efforts are needed to identify a specific phenotype associated with this gene crossing the current diagnostic categories.