• KSBB Journal
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• 제20권6호
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• pp.418-424
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• 2005

Rhodobacter sphaeroides는 photoheterotrophic 조건에서 성장을 하면서 질소고정효소인 nitrogenase에 의해 수소를 발생시킨다. 이 nitrogenase는 ammonium ion이 존재할 때, PII 계열 단백질인 GlnB와 GlnK에 의해 negative regulation을 받게 된다. 본 연구에서는 glnB와 glnK 유전자를 interruption하여 수소생성의 증진을 꾀하였다. 그 결과, parental strain이나 glnB 혹은 glnK 유전자 하나만을 interruption 시켰을 경우, 암모니움 이온에 의해 nitrogenase 활성이 저해를 받고 있었으나, glnB, glnK 모두를 interruption 시켰을 때, 암모니움 이온에 의한 저해 효과가 줄어드는 것을 볼 수 있었다. 또한 이러한 glnB-glnK double mutant에 nifDK gene을 in trans로 넣어 nitrogenase의 dosage를 높였을 경우, 수소 생성이 약 30% 가량 증진되었다는 것을 볼 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.251-258
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• 2001

In Gram(+) bacteria and organelles in higher eukarotes, $Gln-tRNA^{Gln}$ utilized for protein biosynthesis is formed by a tRNA-dependent amino acid transformation using mischarged $Gln-tRNA^{Gln}$ as the intermediate. In this study, the gatCAB gene encoding $Gln-tRNA^{Gln}$ amidotransferase (Glu-AdT) of Staphylococcus aureus was cloned and its nucleotide sequence wa determined. The S. aureus gatCAB gene was organized in an operon structure consisting of three open reading frames (gatC, gatA, and gatB), similar to that of Bacillus subtilis. The gene sequences for the A and B subunits of$Gln-tRNA^{Gln}$ amidotransferase showed significant homology (77 and 87% homology with amino acid sequence) with the gatA and gatB genes of B. subtilis, yet the C subunit (gatC) showed a relatively lowe homology with the B. subtilis gatC gene and other orthologues. The cloned S. aureus <$Gln-tRNA^{Gln}$ amidotransferase gene was highly expressed in Escherichia coli, and the resulting crude enzyme could convert misacylated <$Gln-tRNA^{Gln}$ into $Gln-tRNA^{Gln}$ in vitro.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5721-5724
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• 2012

We conducted this study to detect associations between XRCC1 Arg399Gln and XPD Lys751Gln genotypes and survival of colorectal cancer patients treated with 5-FU/oxalipatin chemotherapy. We included 289 Chinese patients with advanced colorectal cancer, who had received 5-FU/oxalipatin chemotherapy as first-line treatment from January 2005 to January 2007. All patients were followed up till Nov. 2011. Genotyping for XRCC1 Arg399Gln and XPD Lys751Gln polymorphisms was based upon duplex polymerase-chain-reaction with the PCR-RFLP method. In our study, we found the XRCC1 399 Gln/Gln genotype to confer significantly higher rates of response to chemotherapy when compared to the Arg/Arg genotype [OR (95% CI)= 2.56(1.57-2.55)]. patients with the XPD 751 Gln/Gln genotype had significantly higher rates of response to chemotherapy [OR (95% CI)= 1.54(0.87-2.65)] and those with the XRCC1 399 Gln/Gln genotype had a longer average survival time and significantly lower risk of death than did those with the Arg/Arg genotype [HR (95% CI)= 0.66(0.36-0.95)]. Similarly, those carrying the XPD 751Gln/Gln genotype had 0.51-fold the risk of death of those with XPD 751Lys/Lys [HR (95% CI)= 0.51(0.33 -0.94)]. In conclusion, it is suggested that the XRCC1 Arg399Gln and XPD Lys751Gln polymorphisms should be routinely assessed to determine colorectal patients who are more likely to benefit from 5-FU/oxalipatin chemotherapy.

• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4443-4448
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• 2014

Background: A number of studies have reported the association of X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln polymorphism with susceptibility to hepatocellular carcinoma (HCC). However, the results were inconsistent and inconclusive. The aim of this study was to comprehensively explore the association of XRCC1 Arg399Gln variant with HCC risk. Materials and Methods: Systematic searches of PubMed, Elsevier, Science Direct, CNKI and Chinese Biomedical Literature Database were performed. Pooled odds ratio (OR) with 95% confidence intervals (CI) was calculated to estimate the strength of association. Results: Overall, we observed an increased HCC risk among subjects carrying XRCC1 codon 399 Gln/Gln, Arg/Gln and Gln/Gln+Arg/Gln genotypes (OR=1.20, 95%CI: 1.05-1.38, OR=1.16, 95%CI: 1.05-1.28, and OR=1.14, 95%CI: 1.04-1.24, respectively) based on 20 studies including 3374 cases and 4633 controls. In subgroup analysis, we observed an increased risk of XRCC1 codon 399 Gln/Gln, Arg/Gln and Gln/Gln+Arg/Gln polymorphisms for HCC in hospital-based study (OR=1.25, 95%CI: 1.03-1.51, OR=1.21, 95%CI: 1.07-1.36 and OR=1.18, 95%CI: 1.06-1.31, respectively) and in Asian population (OR=1.19, 95%CI: 1.03-1.38, OR=1.17, 95%CI: 1.04-1.30 and OR=1.14, 95%CI: 1.04-1.25, respectively). Limiting the analysis to the studies with controls in agreement with Hardy-Weinberg equilibrium (HWE), we observed an increased HCC risk among Gln/Gln, Arg/Gln and Gln/ Gln+Arg/Gln genotype carriers (OR=1.17, 95%CI: 1.05-1.29, OR=1.12, 95%CI: 1.00-1.25 and OR=1.11, 95%CI: 1.02-1.21, respectively). Conclusions: This updated meta-analysis results suggest that XRCC1 Arg399Gln variants may contribute to HCC risk. Well-designed studies with larger sample size were required to further verify our findings.

• Journal of Microbiology
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• 제42권2호
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• pp.111-116
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• 2004

It is known that Bacillus subtilis glutamyl-tRNA synthetase (GluRS) mischarges E. coli $tRNA_{1}$$^{Gln}$ with glutamate in vitro. It has also been established that the expression of B. subtilis GluRS in Escherichia coli results in the death of the host cell. To ascertain whether E. coli growth inhibition caused by B. subtilis GluRS synthesis is a consequence of Glu-$tRNA_{1}$$^{Gln}$ formation, we constructed an in vivo test system, in which B. subtilis GluRS gene expression is controlled by IPTG. Such a system permits the investigation of factors affecting E. coli growth. Expression of E. coli glutaminyl-tRNA synthetase (GlnRS) also amelio-rated growth inhibition, presumably by competitively preventing $tRNA_{1}$$^{Gln}$ misacylation. However, when amounts of up to 10 mM L-glutamine, the cognate amino acid for acylation of $tRNA_{1}$$^{Gln}$, were added to the growth medium, cell growth was unaffected. Overexpression of the B. subtilis gatCAB gene encoding Glu-$tRNA^{Gln}$ amidotransferase (Glu-AdT) rescued cells from toxic effects caused by the formation of the mis-charging GluRS. This result indicates that B. subtilis Glu-AdT recognizes the mischarged E. coli Glu-$tRNA_{1}$$^{Gln}$, and converts it to the cognate Gln-$tRNA_{1}$$^{Gln}$ species. B. subtilis GluRS-dependent Glu-$tRNA_{1}$$^{Gln}$ formation may cause growth inhibition in the transformed E. coli strain, possibly due to abnormal protein synthesis.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.355-358
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• 2013

XRCC1 genetic polymorphisms could be associated with increased risk of various cancer, including hepatocellular carcinoma (HCC), the fifth most common cancer. We here conducted a study to explore the role of selective SNPs of the XRCC1 and XPD genes in the prognosis of HCC. A total of 231 cases were collected, and genotyping of XRCC1 Arg194Trp, XRCC1 Arg399Gln, XPD Lys751Gln and XPD Asp312Asn was performed by duplex polymerase-chain-reaction with the confronting-two-pair primer method. Our findings indicated XRCC1 399Gln/Gln genotype was associated with a significant difference in the median survival time compared with patients carrying Arg/Trp and Arg/Arg genotypes, and individuals with XPD 751 Gln/ Gln genotype had a significantly greater survival time than patients carrying Lys/Lys and Lys/Gln genotypes. The Cox's regression analysis showed individuals carrying XRCC1 399Trp/Trp genotype had 0.55 fold risk of death from HCC than Arg/Arg genotype. Similarly, XPD 751Gln/Gln had a strong decreasein comparison to XPD Lys/Lys carriers with an HR of 0.34. These results suggest that polymorphisms in XRCC1 and XPD may have functional significance in the prognosis of HCC.

• Asian Pacific Journal of Cancer Prevention
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• 제16권2호
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• pp.495-500
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• 2015

Background: Published studies have reported relationships between X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln polymorphism and lung cancer risk in Chinese population. However, the epidemiological results remained controversial. The objective of this study was to clarify the association of XRCC1 Arg399Gln polymorphism with lung cancer risk in the Chinese population. Materials and Methods: Systematic searches were performed through the database of Medline/Pubmed, Web of Science, Embase, CNKI and WanFang Medical Online. Odds ratios (ORs) with 95% confidence interval (95%CI) were calculated to estimate the strength of the association. Results: Overall, we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Gln/Gln genotype (OR=1.36, 95%CI: 1.09-1.71) in the Chinese population on the basis of 19 studies with 5,416 cases and 5,782 controls. We did not observe any association between XRCC1 codon 399 Arg/Gln and Arg/Gln+Gln/Gln polymorphisms and lung cancer risk (OR=1.00, 95%CI: 0.92-1.08 and OR=1.05, 95%CI: 0.97-1.13, respectively). Limiting the analysis to studies with controls in agreement with Hardy-Weinberg equilibrium (HWE), we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Gln/Gln genotype (OR=1.18, 95%CI: 1.01-1.38). When stratified by source of control, we observed an increased lung cancer risk among subjects carrying XRCC1 codon 399 Arg/Gln+Gln/Gln genotype on the basis of hospitalized patient-based controls (OR=1.21, 95%CI: 1.04-1.42) and among subjects carrying XRCC1 codon 399 Gln/Gln genotype on the basis of healthy subject-based controls (OR=1.22, 95%CI: 1.04-1.43). Conclusions: Our findings indicated that certain XRCC1 Arg399Gln variants might affect the susceptibility of lung cancer in Chinese population. Larger sample size studies are required to confirm our findings.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.5275-5279
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• 2013

Background: The XRCC1 (X-ray repair cross complimenting group-I) gene in BER (base excision repair) pathway is essential for DNA repair process. Polymorphisms in this gene are associated with variations in the repair efficiency which might predispose individuals to development of various cancers. Two variants of XRCC1gene (at codon 399), Gln/Gln and Arg/Gln, have been shown to be related to lowered DNA repair capacity and increased genomic instability in multiple studies. Hence our investigation focused on genotyping these variants to correlate with other multiple risk factors in lung cancer (NSCLC) patients since we hypothesized that these variants of the XRCC1 gene might influence disease susceptibility. Materials and Methods: We examined the frequency of the polymorphism in one hundred cases and an almost equal number of controls after recording their demographics with a structured questionnaire. Genomic DNA from blood samples was extracted for PCR studies, followed by RFLP to determine the variants. The significance of the data was statistically analyzed. Results: The three genotypes in cases and controls were Arg/Arg (40% and 54.45%); Gln/Gln (19% and 9.90%), and Arg/Gln (41.0% and 35.64%) respectively. Among these 3 genotypes, we found Gln/Gln and Arg/Gln to show association with lung cancer. Correlating these genotypes with several parameters, we also found that these two variants were associated with risk in males (p<0.05) and with smoking habits (p<0.05). In females Arg/Gln genotype showed association with stage of the disease (p=0.04). This is the first report in South Indian scenario where Arg399Gln genotypes were found to be associated with stage of the disease in females. Conclusions: It is concluded that XRCC1 genotypes Gln/Gln and Arg/Gln may influence cancer susceptibility in patients with smoking habits and these functional SNPs in XRCC1 gene may act as attractive candidate biomarkers in lung cancer for diagnosis and prognosis.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.1993-1999
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• 2014

Background: This study aimed to explore the role of XRCC1 (Arg399Gln) and XPD (Lys751Gln) gene polymorphisms, lifestyle and environmental factors as well as their possible interactions in propensity to develop lung cancer in a population with high incidence from North East India. Materials and Methods: A total of 272 lung cancer cases and 544 controls were collected and XRCC1 (Arg399Gln) and XPD (Lys751Gln) genotypes were analyzed using a polymerase chain reaction based restriction fragment length polymorphism assay. Conditional multiple logistic regression analysis was used to calculate adjusted odds ratios and 95% confidence intervals after adjusting for confounding factors. Results: The combined Gln/Gln genotype of XRCC1 and XPD genes (OR=2.78, CI=1.05-7.38; p=0.040) was significantly associated with increased risk for lung cancer. Interaction of XRCC1Gln/Gln genotype with exposure of wood combustion (OR=2.56, CI=1.16-5.66; p=0.020), exposure of cooking oil fumes (OR=3.45, CI=1.39-8.58; p=0.008) and tobacco smoking (OR=2.54, CI=1.21-5.32; p=0.014) and interaction of XPD with betel quid chewing (OR=2.31, CI=1.23-4.32; p=0.009) and tobacco smoking (OR=2.13, CI=1.12-4.05; p=0.022) were found to be significantly associated with increased risk for lung cancer. Conclusions: Gln/Gln alleles of both XRCC1 and XPD genes appear to amplify the effects of household exposure, smoking and betel quid chewing on lung cancer risk in the study population.

• Asian-Australasian Journal of Animal Sciences
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• 제30권2호
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• pp.236-245
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• 2017

Objective: The study was to investigate the effects of alanyl-glutamine (Ala-Gln) and glutamine (Gln) supplementation on the intestinal mucosa barrier in piglets. Methods: A total of 180 barrows with initial weight $10.01{\pm}0.03kg$ were randomly allocated to three treatments, and each treatment consisted of three pens and twenty pigs per pen. The piglets of three groups were fed with control diet [0.62% alanine (Ala)], Ala-Gln diet (0.5% Ala-Gln), Gln diet (0.34% Gln and 0.21% Ala), respectively. Results: The results showed that in comparison with control diet, dietary Ala-Gln supplementation increased the height of villi in duodenum and jejunum (p<0.05), Gln supplementation increased the villi height of jejunum (p<0.05), Ala-Gln supplementation up-regulated the mRNA expressions of epidermal growth factor receptor and insulin-like growth factor 1 receptor in jejunal mucosa (p<0.05), raised the mRNA expressions of Claudin-1, Occludin, zonula occludens protein-1 (ZO-1) and the protein levels of Occludin, ZO-1 in jejunal mucosa (p<0.05), Ala-Gln supplementation enlarged the number of goblet cells in duodenal and ileal epithelium (p<0.05), Gln increased the number of goblet cells in duodenal epithelium (p<0.05) and Ala-Gln supplementation improved the concentrations of secretory immunoglobulin A and immunoglobulin G in the jejunal mucosa (p<0.05). Conclusion: These results demonstrated that dietary Ala-Gln supplementation could maintain the integrity of small intestine and promote the functions of intestinal mucosa barriers in piglets.