排序方式: 共有28条查询结果,搜索用时 15 毫秒
1.
2.
3.
Kannipa Tasanapak Uraiwan Masud-Tippayasak Kazunobu Matsushita Wichien Yongmanitchai Gunjana Theeragool 《Journal of microbiology (Seoul, Korea)》2013,51(6):783-790
The aspS gene encoding Aspartyl-tRNA synthetase (AspRS) from a thermotolerant acetic acid bacterium, Acetobacter pasteurianus SKU1108, has been cloned and characterized. The open reading frame (ORF) of the aspS gene consists of 1,788 bp, encoding 595 amino acid residues. The highly conserved Gly-Val-Asp-Arg ATP binding motif (motif 3) is located at the position 537–540 in the C-terminus. Deletion analysis of the aspS gene upstream region suggested that the promoter is around 173 bp upstream from the ATG initiation codon. Interestingly, transformation with the plasmids pGEM-T138, pUC138, and pCM138 synthesizing 138 amino acid C-terminal fragments of AspRS, that carry the ATP binding domain, caused E. coli cell lengthening at 37 and 42°C. Moreover, E. coli harboring pUC595 (synthesizing all 595 amino acids) and a disordered aspS gene in pGEM-T138 had normal rod shapes. The normal rod shape was observed in E. coli harboring pD539V following site-directed mutagenesis of the ATP binding domain. We propose that over-production of truncated C-terminal peptides of AspRS may cause sequestration of intracellular ATP in E. coli, leaving less ATP for cell division or shaping cell morphology. 相似文献
4.
Moonmangmee D Fujii Y Toyama H Theeragool G Lotong N Matsushita K Adachi O 《Bioscience, biotechnology, and biochemistry》2001,65(12):2763-2772
A quinoprotein catalyzing oxidation of cyclic alcohols was found in the membrane fraction for the first time, after extensive screening among aerobic bacteria. Gluconobacter frateurii CHM 9 was finally selected in this study. The enzyme tentatively named membrane-bound cyclic alcohol dehydrogenase (MCAD) was found to occur specifically in the membrane fraction, and pyrroloquinoline quinone (PQQ) was functional as the primary coenzyme in the enzyme activity. MCAD catalyzed only oxidation reaction of cyclic alcohols irreversibly to corresponding ketones. Unlike already known cytosolic NAD(P)H-dependent alcohol-aldehyde or alcohol-ketone oxidoreductases, MCAD was unable to catalyze the reverse reaction of cyclic ketones or aldehydes to cyclic alcohols. MCAD was solubilized and purified from the membrane fraction of the organism to homogeneity. Differential solubilization to eliminate the predominant quinoprotein alcohol dehydrogenase (ADH), and the subsequent two steps of column chromatographies, brought MCAD to homogeneity. Purified MCAD had a molecular mass of 83 kDa by SDS-PAGE. Substrate specificity showed that MCAD was an enzyme oxidizing a wide variety of cyclic alcohols. Some minor enzyme activity was found with aliphatic secondary alcohols and sugar alcohols, but not primary alcohols, differentiating MCAD from quinoprotein ADH. NAD-dependent cytosolic cyclic alcohol dehydrogenase (CCAD) in the same organism was crystallized and its catalytic and physicochemical properties were characterized. Judging from the catalytic properties of CCAD, it was apparent that CCAD was distinct from MCAD in many respects and seemed to make no contributions to cyclic alcohol oxidation. 相似文献
5.
JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献6.
Utility of the white gene in estimating phylogenetic relationships among mosquitoes (Diptera: Culicidae) 总被引:2,自引:0,他引:2
The utility of a nuclear protein-coding gene for reconstructing
phylogenetic relationships within the family Culicidae was explored.
Relationships among 13 species representing three subfamilies and nine
genera of Culicidae were analyzed using a 762-bp fragment of coding
sequence from the eye color gene, white. Outgroups for the study were two
species from the sister group Chaoboridae. Sequences were determined from
clone PCR products amplified from genomic DNA, and aligned following
conceptual intron splicing and amino acid translation. Third codon
positions were characterized by high levels of divergence and biased
nucleotide composition, the intensity and direction of which varied among
taxa. Equal weighting of all characters resulted in parsimony and
neighboring-joining trees at odds with the generally accepted phylogenetic
hypothesis based on morphology and rDNA sequences. The application of
differential weighting schemes recovered the traditional hypothesis, in
which the subfamily Anophelinae formed the basal clade. The subfamily
Toxorhynchitinae occupied an intermediate position, and was a sister group
to the subfamily Culicinae. Within Culicinae, the genera Sabethes and
Tripteroides formed an ancestral clade, while the Culex-Deinocerites and
Aedes- Haemagogus clades occupied increasingly derived positions in the
molecular phylogeny. An intron present in the Culicinae- Toxorhynchitinae
lineage and one outgroup taxon was absent in the basal Anophelinae lineage
and the second outgroup taxon, suggesting that intron insertions or
deletions may not always be reliable systematic characters.
相似文献
7.
8.
Shinagawa E Toyama H Matsushita K Tuitemwong P Theeragool G Adachi O 《Bioscience, biotechnology, and biochemistry》2006,70(4):850-857
Membrane-bound NADP-independent formaldehyde-oxidizing enzyme was purified to homogeneity from the membrane of Acetobacter sp. SKU 14 isolated in Thailand. The enzyme was solubilized from the membrane fraction of glycerol-grown cells with 1% Tween 20 at pH 2.85, and purified to homogeneity through the steps of column chromatographies on DEAE-Sephadex A-50 and Q-Sepharose in the presence of 0.1% Tween 20 and 0.1% Triton X-100. The enzyme purified together with a cytochrome c showed a single protein band on native-PAGE, and was dissociated into three different subunits upon SDS-PAGE with molecular masses of 78 kDa, 55 kDa, and 18 kDa. The purified enzyme was finally characterized as a quinoprotein alcohol dehydrogenase (QADH), and this is the first indication that QADH highly oxidizes formaldehyde. The substrate specificity of the enzyme was found to be broad toward aldehydes and alcohols, and alcohols, especially n-butanol, n-propanol, and ethanol, were oxidized more rapidly than formaldehyde. 相似文献
9.
Anton GT Terwisscha van Scheltinga Marjolijn N Lub-de Hooge Keelara Abiraj Carolien P Schr?der Linda Pot Birgit Bossenmaier Marlene Thomas Gabriele H?lzlwimmer Thomas Friess Jos GW Kosterink Elisabeth GE de Vries 《MABS-AUSTIN》2014,6(4):1051-1058
The humanized monoclonal antibody with high affinity for the human epidermal growth factor receptor (HER) 3, RG7116, is a glycoengineered, IgG1 class antibody. By labeling RG7116 with zirconium-89 (89Zr) we aimed to visualize in vivo HER3 expression and study the biodistribution of this antibody in human tumor-bearing mice. Biodistribution of 89Zr-RG7116 was studied in subcutaneously xenografted FaDu tumor cells (HER3-positive). Dose-dependency of 89Zr-RG7116 organ distribution and specific tumor uptake was assessed by administering doses ranging from 0.05 to 10 mg/kg RG7116 to SCID/Beige mice. Biodistribution was analyzed at 24 and 144 h after injection. MicroPET imaging was performed at 1, 3, and 6 days after injection of 1.0 mg/kg 89Zr-RG7116 in the FaDu, H441, QG-56 and Calu-1 xenografts with varying HER3 expression. The excised tumors were analyzed for HER3 expression. Biodistribution analyses showed a dose- and time-dependent 89Zr-RG7116 tumor uptake in FaDu tumors. The highest tumor uptake of 89Zr-RG7116 was observed in the 0.05 mg/kg dose group with 27.5%ID/g at 144 h after tracer injection. MicroPET imaging revealed specific tumor uptake of 89Zr-RG7116 in FaDu and H441 models with an increase in tumor uptake over time. Biodistribution data was consistent with the microPET findings in FaDu, H441, QG56 and Calu-1 xenografts, which correlated with HER3 expression levels. In conclusion, 89Zr-RG7116 specifically accumulates in HER3 expressing tumors. PET imaging with this tracer provides real-time non-invasive information about RG7116 distribution, tumor targeting and tumor HER3 expression levels. 相似文献
10.