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91.
92.
Koki Kuramochi Kohsuke Uchimura Atsushi Kurata Tohru Kobayashi Yuu Hirose Takeshi Miura Noriaki Kishimoto Ron Usami Koki Horikoshi 《Extremophiles : life under extreme conditions》2016,20(4):471-478
An endo β-1,4-xylanase (XynE15) from a culture broth of a deep subseafloor microorganism, Microcella alkaliphila JAM-AC0309, was purified to homogeneity. The molecular mass of XynE15 was approximately 150 kDa as judged by SDS-PAGE. The optimal pH and temperature for hydrolysis of xylan were pH 8 and 65 °C. The enzyme was stable to incubation for 30 min at up to 75 °C, and the half-life at 50 °C was 48 h. XynE15 hydrolyzed arabinoxylan, oat spelt xylan, and birchwood xylan well, but not avicel, carboxymethylcellulose, or arabinan. Xylooligosaccharides were hydrolyzed to mainly xylobiose from higher than xylotetraose. The genome sequencing analysis of strain JAM-AC03039 revealed that XynE15 was composed of 1,319 amino acids with one catalytic domain and three carbohydrate-binding domains belonging to glycoside hydrolase (GH) family 10 and carbohydrate-binding module (CBM) family 4, respectively. 相似文献
93.
ABSTRACTIn June, 2015, the Purine and Pyrimidine Society organized the 16th biennial symposium on Purine and Pyrimidine metabolism at the Faculty House of Columbia University, New York City. This exciting meeting focused on these important molecules, new developments in inborn errors of metabolism; therapeutic analogs. In addition, the biochemistry of mammalian and non-mammalian systems were discussed. Due to significant advances in molecular medicine, the boundaries between clinical and basic sciences have merged into exciting translational research, of which a small portion was highlighted in the presymposium. 相似文献
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Andrew Post T. Blaine Hoshizaki Clara Karton J. Michio Clark Lauren Dawson Janie Cournoyer 《Computer methods in biomechanics and biomedical engineering》2019,22(6):631-643
The purpose of this research was to conduct reconstructions of concussive and non-concussive impacts in ice hockey to determine the biomechanics and thresholds of concussive injury in ice hockey. Videos of concussive and non-concussive impacts in an elite professional ice hockey league in North America were reconstructed using physical and finite element model methods. Eighty concussive and 45 non-concussive events were studied. Logistic regressions indicate significant thresholds for concussion for linear/rotational acceleration and CSDM10%. Impacts in ice hockey were mostly long duration events, longer than 15?ms. These results have significant implications for helmet standards and development to prevent concussion. 相似文献
96.
Urai M Yoshizaki H Anzai H Ogihara J Iwabuchi N Harayama S Sunairi M Nakajima M 《Carbohydrate research》2007,342(7):933-942
Rhodococcus erythropolis PR4 is a marine bacterium that can degrade various alkanes including pristane, a C(19) branched alkane. This strain produces a large quantity of extracellular polysaccharides, which are assumed to play an important role in the hydrocarbon tolerance of this bacterium. The strain produced two acidic extracellular polysaccharides, FR1 and FR2, and the latter showed emulsifying activity toward clove oil, whereas the former did not. FR2 was composed of D-galactose, D-glucose, D-mannose, D-glucuronic acid, and pyruvic acid at a molar ratio of 1:1:1:1:1, and contained 2.9% (w/w) stearic acid and 4.3% (w/w) palmitic acid attached via ester bonds. Therefore, we designated FR2 as a PR4 fatty acid-containing extracellular polysaccharide or FACEPS. The chemical structure of the PR4 FACEPS polysaccharide chain was determined by 1D (1)H and (13)C NMR spectroscopies as well as by 2D DQF-COSY, TOCSY, HMQC, HMBC, and NOESY experiments. The sugar chain of PR4 FACEPS was shown to consist of tetrasaccharide repeating units having the following structure: [structure: see text]. 相似文献
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A FRET-based analysis of SNPs without fluorescent probes 总被引:2,自引:0,他引:2
Fluorescence resonance energy transfer (FRET) is a simple procedure for detecting specific DNA sequences, and is therefore used in many fields. However, the cost is relatively high, because FRET-based methods usually require fluorescent probes. We have designed a cost-effective way of using FRET, and developed a novel approach for the genotyping of single nucleotide polymorphisms (SNPs) and allele frequency estimation. The key feature of this method is that it uses a DNA-binding fluorogenic molecule, SYBR Green I, as an energy donor for FRET. In this method, single base extension is performed with dideoxynucleotides labeled with an orange dye and a red dye in the presence of SYBR Green I. The dyes incorporated into the extended products accept energy from SYBR Green I and emit fluorescence. We have validated the method with ten SNPs, which were successfully discriminated by end-point measurements of orange and red fluorescence intensity in a microplate fluorescence reader. Using a mixture of homozygous samples, we also confirmed the potential of this method for estimation of allele frequency. Application of this strategy to large-scale studies will reduce the time and cost of genotyping a vast number of SNPs. 相似文献
99.
In-gel competitive reassociation (IGCR) is a method for differential subtraction of polymorphic (RFLP) DNA fragments between two DNA samples of interest without probes or specific sequence information. Previously IGCR was used to enrich and isolate polymorphic genomic DNA fragments from mouse and human genomic DNA. We have modified the original IGCR procedures specifically for the isolation of polymorphic mRNAs in the form of cDNAs. Here we demonstrate that polymorphic mRNAs (cDNAs) between BALB/c and C57BL/6J mice that result from alterations at restriction sites and insertions-deletions are isolated with high efficiency by the IGCR procedure. A high proportion of the cDNAs was enriched by IGCR and 80% of the enriched clones were found to be actual RFLP fragments, indicating that the procedure is also applicable to direct screening for polymorphic mRNAs. 相似文献
100.
Hisako?Miki-HirosigeEmail author Yuko?Yamanaka Sumio?Nakamura Shigeaki?Kurata Hisashi?Hirano 《Sexual plant reproduction》2004,16(5):209-214
Pollen proteins of Lilium longiflorum were examined at different developmental stages (young, mature and cultured) using two-dimensional differential gel electrophoresis. Quantitative changes of six proteins (MP1–MP6) during pollen development were observed in the acidic and low molecular weight region. After water absorption on the culture medium, the quantities of all six proteins were drastically changed. Mass spectrometric analysis revealed that MP2, MP3, MP4 and MP6 are late embryogenesis abundant (LEA) (D-7) protein, profilin 3, profilin 1 and enolase, respectively. The remaining two proteins (MP1 and MP5) could not be identified by mass spectrometric analysis. Immunogold electron microscopic examination showed the presence of these proteins in different regions: MP1 around lipid bodies, suggesting possible involvement in lipid metabolism, MP4 near actin in the cytoplasm, indicating the possibility of its interaction with actin in the regulatory pathways of pollen, and MP2 and MP6 in the cytoplasm. 相似文献