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991.
992.
Kim HM Lee YG Patel DH Lee KH Lee DS Bae HJ 《Journal of industrial microbiology & biotechnology》2012,39(7):1081-1089
The endoglucanase (Cel5B) from the filamentous fungus Gloeophyllum trabeum was cloned and expressed without a signal peptide, and alanine residue 22 converted to glutamine in Pichia pastoris GS115. The DNA sequence of Cel5B had an open reading frame of 1,077 bp, encoding a protein of 359 amino acid residues with a molecular weight of 47 kDa. On the basis of sequence similarity, Cel5B displayed active site residues at Glu-175 and Glu-287. Both residues lost full hydrolytic activity when replaced with alanine through point mutation. The purified recombinant Cel5B showed very high specific activity, about 80- to 1,000-fold and 13- to 70-fold in comparison with other endoglucanases and cellobiohydrolase, on carboxymethylcellulose and filter paper, respectively, at pH 3.5 and 55°C. Cel5B displayed bifunctional characteristics under acidic conditions. The kinetic properties of the enzyme determined using a Lineweaver-Burk plot indicated that Cel5B is a catalytically efficient cellulolytic enzyme. These results suggest that Cel5B has high bifunctional endo- and exoglucanase activity under acidic conditions and is a good candidate for bioconversion of lignocellulose. 相似文献
993.
Expression of the Arabidopsis
AtMYB44 gene confers drought/salt-stress tolerance in transgenic soybean 总被引:1,自引:0,他引:1
Jun Sung Seo Hwang Bae Sohn Kaeyoung Noh Choonkyun Jung Ju Hee An Christopher M. Donovan David A. Somers Dae In Kim Soon-Chun Jeong Chang-Gi Kim Hwan Mook Kim Suk-Ha Lee Yang Do Choi Tae Wha Moon Chung Ho Kim Jong-Joo Cheong 《Molecular breeding : new strategies in plant improvement》2012,29(3):601-608
994.
The present study investigated the diagnostic value of an ELISA for the detection of Clonorchis sinensis antigen in the feces of experimentally infected rats. A mouse polyclonal IgG antibody against adult C. sinensis crude antigen (CsAg) was used to capture the C. sinensis coproantigen. The detection limit for pure CsAg was 20 ng/ml in sample buffer and 40 ng/ml in uninfected fecal extract. The test was evaluated using a follow-up of five groups of rats experimentally infected with 100, 50, 10, 5 and 1 metacercariae of C. sinensis and an uninfected control group. Coproantigen was detected in all infected groups of rats from 2 weeks of infection, whereas fecal eggs were not observed until 3 weeks of infection. As the infection period progressed, the fecal CsAg concentration increased in all groups of infected rats, even those infected with a single metacercaria. The fecal CsAg concentration was correlated positively with fecal egg counts and worm burden. This coproantigen capture ELISA is highly sensitive for the detection of CsAg in rat feces, and with further development, should be useful for mass screening of human subjects in clonorchiasis-endemic areas. 相似文献
995.
DNA metabolic processes such as DNA replication, recombination, and repair are fundamentally important for the maintenance
of genome integrity and cell viability. Although a large number of proteins involved in these pathways have been extensively
studied, many proteins still remain to be identified. In this study, we isolated DNA-binding proteins from Saccharomyces cerevisiae using DNA-cellulose columns. By analyzing the proteins using mass spectrometry, an uncharacterized protein, Cmr1/YDL156W,
was identified. Cmr1 showed sequence homology to human Damaged-DNA binding protein 2 in its C-terminal WD40 repeats. Consistent
with this finding, the purified recombinant Cmr1 protein was found to be intrinsically associated with DNA-binding activity
and exhibited higher affinity to UV-damaged DNA substrates. Chromatin isolation experiments revealed that Cmr1 localized in
both the chromatin and supernatant fractions, and the level of Cmr1 in the chromatin fraction increased when yeast cells were
irradiated with UV. These results suggest that Cmr1 may be involved in DNA-damage responses in yeast. 相似文献
996.
The aim of this study was to explore whether the cytotoxic T lymphocyte antigen-4 (CTLA-4) +49 A/G polymorphism confers susceptibility
to rheumatoid arthritis (RA). A meta-analysis was conducted on the associations between CTLA-4 +49 A/G polymorphism and RA
using; 1) allele contrast, 2) the recessive model, 3) the dominant model, and 4) an additive model. A total of 19 studies,
5,752 RA patients and 5,508 controls, encompassing 9 Caucasian, 8 Asian, 1 Mexican, and 1 Tunisian population were included
in this meta-analysis. Ethnicity-specific meta-analysis was performed on Caucasian and Asian populations. Meta-analysis of
the CTLA-4 +49 A/G polymorphism revealed an association between RA and the CTLA-4 +49 G allele in all 11,260 study subjects
(odds ratio (OR) 1.118, 95% confidence interval (CI) 1.033–1.210, P = 0.005). Stratification by ethnicity showed an association between the CTLA-4 +49 G allele and RA in Asians (OR 1.164, 95%
CI 1.056–1.283, P = 0.002), but no evidence of an association in Caucasians (OR 1.085, 95% CI 0.973–1.209, P = 0.431). Furthermore, associations were found between RA and the CTLA-4 +49 A/G polymorphism in Asians using the dominant
and additive models, but not using the recessive model. On the other hand, no association was found between RA and the CTLA-4
+49 A/G polymorphism using the recessive, dominant, or additive models in Caucasians. This meta-analysis demonstrates that
the CTLA-4 +49 A/G polymorphism confers susceptibility to RA in Asians, but not in Caucasians. 相似文献
997.
Pasaje CF Bae JS Park BL Kim JH Cheong HS Uh ST Park CS Shin HD 《Molecular biology reports》2012,39(5):5913-5919
Modest effects of genes in various pathways are significant in the etiology of complex human diseases, including aspirin exacerbated
respiratory disease (AERD). By functioning as a relevant component of respiratory processes, the human kinesin family member C1 (KIFC1) is hypothesized to play a role in AERD pathogenesis. A case–control analysis was carried out by comparing the genotype distribution
of six KIFC1 single-nucleotide polymorphisms between 93 AERD cases and 96 aspirin-tolerant asthma controls in a Korean population. After
controlling for confounds, logistic and regression models via various modes of genetic inheritance facilitated the association
analysis. Initial results revealed significant association at 0.05 level of significance between several KIFC1 variations and AERD (P = 0.01–0.05, OR = 1.81–1.90) as well as fall rate of forced expiratory volume in the 1st second, an important diagnostic
marker of airways constriction (P = 0.04–0.05). However, the signals were not deemed significant after multiple testing corrections (P
corr > 0.05). Although the results do not support a major role of KIFC1 in AERD pathogenesis in a Korean asthma cohort, further replication and validation studies are required to clarify the current
findings. 相似文献
998.
The aim of this study was to determine whether the interleukin-10 (IL-10) polymorphisms confer susceptibility to rheumatoid
arthritis (RA). A meta-analysis was conducted on the associations between the IL-10 −1082 G/A, −592 C/A, −892 C/T and IL-10.R
polymorphisms and RA using; (1) allele contrast, (2) the recessive model, (3) the dominant model, and (4) the additive model.
A total of 16 studies (19 comparisons) involving 2647 RA patients and 3383 controls were considered in the meta-analysis.
Meta-analysis of the IL-10 −1082 G/A polymorphism showed no association with RA in the study subjects, or in European or Asian
subjects. However, meta-analysis of the −1082 G allele in 4 studies in Hardy–Weinberg equilibrium showed a significant association
with RA (OR = 1.217, 95% CI = 1.027–1.442, P = 0.0236). In contrast, meta-analysis of the C allele, the CC genotype, and of the CC versus the AA genotype of the IL-10
−592 C/A polymorphism showed significant associations with RA. The overall ORs of the associations between the C allele and
RA were 0.684 and 0.758 (95% CI = 0.494–0.946, P = 0.022; 95% CI = 0.475–1.210, P = 0.045) in all study subjects and Asians. Meta-analysis of the CC + CT versus TT genotype and of the CC versus TT genotype
of the IL-10 −892 C/T polymorphism revealed significant associations with RA. The overall OR of the association between the
C allele carrier and RA was 0.552 (95% CI = 0.375–0.812, P = 0.003). No association was found between the IL10.R2 alleles and RA. This meta-analysis suggests that the IL-10 −592 C/A
polymorphism confers susceptibility to RA in Asians and that the IL-10 −1082 G/A and −892 C/T polymorphisms are associated
with RA susceptibility. These findings suggest the IL-10 genes confer susceptibility to RA. 相似文献
999.
Phenelzine is a potent monoamine oxidase inhibitor that is used in patients with depression. It is also well known that nitric oxide (NO) synthase inhibitors show preclinical antidepressant-like properties, which suggests that NO is involved in the pathogenesis of depression. The purpose of this study was to determine if phenelzine affects the production of NO and tumor necrosis factor-alpha (TNF-α) in activated microglia cells. BV-2 microglia cells and primary microglia cells were cultured in DMEM and DMEM/F12 and then cells were treated with LPS or LPS plus phenelzine for 24?h. The culture medium was collected for determination of NO, TNF-α, and IL-6 and cells were harvested by lysis buffer for Western blot analysis. Phenelzine increased the lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase (iNOS), as well as the release of TNF-α and IL-6 in BV-2 microglia cells. It is also confirmed that phenelzine increased the levels of NO, TNF-α and IL-6 in LPS-activated primary microglia cells. Phenelzine increased nuclear translocation of NF-κB by phosphorylation of IκB-α in LPS-activated microglia cells. These findings suggest that high doses of phenelzine could aggravate inflammatory responses in microglia cells that are mediated by NO and TNF-α. 相似文献
1000.
Kurreeman FA Stahl EA Okada Y Liao K Diogo D Raychaudhuri S Freudenberg J Kochi Y Patsopoulos NA Gupta N;CLEAR investigators Sandor C Bang SY Lee HS Padyukov L Suzuki A Siminovitch K Worthington J Gregersen PK Hughes LB Reynolds RJ Bridges SL Bae SC Yamamoto K Plenge RM 《American journal of human genetics》2012,90(3):524-532
We have previously shown that rheumatoid arthritis (RA) risk alleles overlap between different ethnic groups. Here, we utilize a multiethnic approach to show that we can effectively discover RA risk alleles. Thirteen putatively associated SNPs that had not yet exceeded genome-wide significance (p < 5 × 10(-8)) in our previous RA genome-wide association study (GWAS) were analyzed in independent sample sets consisting of 4,366 cases and 17,765 controls of European, African American, and East Asian ancestry. Additionally, we conducted an overall association test across all 65,833 samples (a GWAS meta-analysis plus the replication samples). Of the 13 SNPs investigated, four were significantly below the study-wide Bonferroni corrected p value threshold (p < 0.0038) in the replication samples. Two SNPs (rs3890745 at the 1p36 locus [p = 2.3 × 10(-12)] and rs2872507 at the 17q12 locus [p = 1.7 × 10(-9)]) surpassed genome-wide significance in all 16,659 RA cases and 49,174 controls combined. We used available GWAS data to fine map these two loci in Europeans and East Asians, and we found that the same allele conferred risk in both ethnic groups. A series of bioinformatic analyses identified TNFRSF14-MMEL1 at the 1p36 locus and IKZF3-ORMDL3-GSDMB at the 17q12 locus as the genes most likely associated with RA. These findings demonstrate empirically that a multiethnic approach is an effective strategy for discovering RA risk loci, and they suggest that combining GWASs across ethnic groups represents an efficient strategy for gaining statistical power. 相似文献