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The (13)C NMR spectra of methyl beta-d-glucopyranoside, methyl beta-d-galactopyranoside, methyl beta-d-xylopyranoside, and methyl beta-l-arabinopyranoside were recorded in CaCl(2)/KCl+D(2)O mixtures and in D(2)O. The chemical shifts of C-1, C-3, and C-5 in the methyl beta-d-glucopyranoside and methyl beta-d-galactopyranoside decrease rapidly as molalities of CaCl(2)/KCl increase, while those of C-1, C-2, and C-3 in the methyl beta-d-xylopyranoside and methyl beta-l-arabinopyranoside decrease rapidly as molalities of CaCl(2)/KCl increase. Cations (Ca(2+)/K(+)) can weakly complex with O in OMe of the pyranosides studied. Results are discussed in terms of the stereochemistry of the pyranoside molecules and the structural properties of the ions. 相似文献
3.
在香蕉EST文库中,通过RACE技术克隆到1个香蕉类甜蛋白基因的全长序列。该序列最大开放阅读框942 bp,编码313个氨基酸。Blast分析发现,它与其他类甜蛋白相似度为56.10%,含有类甜蛋白(TLPs)特有的保守结构域,命名为MaTLP1。系统进化树表明,MaTLP1基因编码蛋白与海枣的亲缘关系较近,与香蕉的进化模式相似。组织特异性分析表明,MaTLP1在根、球茎、假茎中的表达量高,叶中较弱,花和果实中微量表达。实时荧光定量PCR分析显示,在抗病香蕉品种中,接种尖孢镰刀菌古巴专化型(Fusarium oxysporum f.sp.cubense,Foc)枯萎病菌后MaTLP1基因上调表达,在感病香蕉品种接菌2 d后MaTLP1基因受到抑制,虽然在接菌4 d 后上调表达,但是相对于抗病品种上调较小。研究表明,MaTLP1基因可能在香蕉抗枯萎病的过程中起作用。 相似文献
4.
The electrostatic force including the intramolecular Coulombic interactions and the electrostatic contribution of solvation effect were entirely calculated by using the finite difference Poisson-Boltzmann method (FDPB), which was incorporated into the GROMOS96 force field to complete a new finite difference stochastic dynamics procedure (FDSD). Simulations were performed on an insulin dimer. Different relative dielectric constants were successively assigned to the protein interior; a value of 17 was selected as optimal for our system. The simulation data were analyzed and compared with those obtained from 500-ps molecular dynamics (MD) simulation with explicit water and a 500-ps conventional stochastic dynamics (SD) simulation without the mean solvent force. The results indicate that the FDSD method with GROMOS96 force field is suitable to study the dynamics and structure of proteins in solution if used with the optimal protein dielectric constant. 相似文献
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Zhuo Li Jon D. Gabbard Scott Johnson Daniel Dlugolenski Shannon Phan S. Mark Tompkins Biao He 《PloS one》2015,10(3)
H7N9 has caused fatal infections in humans. A safe and effective vaccine is the best way to prevent large-scale outbreaks in the human population. Parainfluenza virus 5 (PIV5), an avirulent paramyxovirus, is a promising vaccine vector. In this work, we generated a recombinant PIV5 expressing the HA gene of H7N9 (PIV5-H7) and tested its efficacy against infection with influenza virus A/Anhui/1/2013 (H7N9) in mice and guinea pigs. PIV5-H7 protected the mice against lethal H7N9 challenge. Interestingly, the protection did not require antibody since PIV5-H7 protected JhD mice that do not produce antibody against lethal H7N9 challenge. Furthermore, transfer of anti-H7 serum did not protect mice against H7N9 challenge. PIV5-H7 generated high HAI titers in guinea pigs, however it did not protect against H7N9 infection or transmission. Intriguingly, immunization of guinea pigs with PIV5-H7 and PIV5 expressing NP of influenza A virus H5N1 (PIV5-NP) conferred protection against H7N9 infection and transmission. Thus, we have obtained a H7N9 vaccine that protected both mice and guinea pigs against lethal H7N9 challenge and infection respectively. 相似文献
7.
Tramadol hydrochloride (TH), has become the most prescribed opioid worldwide. However, its neurotoxicity and abuse potential are not well documented. In the present study, TH administration induced abnormal behavior and body and brain mean weight loss. Two principal metabolites O- and N-desmethyltramadol were detected in the brain tissue, and N-desmethyltramadol was the main metabolite produced. A total of 30 differential protein spots were identified using semi-quantitative 2D-PAGE and proteomic analyses, and classified into 13 categories, in which subtypes of 14-3-3 proteins, creatine kinase, ATP synthase beta chain, and tubulin were identified at the separated location on the gels 3, 3, 4, and 11 times respectively. Many TH responsive proteins have functions related to oxidative stress, including 14-3-3 proteins, creatine kinase BB, ubiquitin carboxy-terminal hydrolase L-1, ATP synthase, synaptosome-associated protein, tubulin and actin. Irrespective of oxidative damage, other pathways affected include apoptosis, energy metabolism, signal disorders, and cytoskeletal structure. Ultrastructural observation of mitochondria showed a series of morphological changes in the case of TH exposure. 相似文献
8.
Qiuchi Wan Zhuo Zheng Kangyou Huang Erwan Guichoux Rémy J. Petit 《Tree Genetics & Genomes》2017,13(4):73
Subtropical East Asia harbours a large plant diversity that is often attributed to allopatric speciation in this topographically complex region characterized by a relative climate stability. Here, we use observations of Platycarya, a widespread subtropical Asian tree genus, to explore the consequences of past climate stability on species’ evolutionary history in subtropical China. This genus has a controversial taxonomy: while it is now prevailingly treated as monotypic, two species have been originally described, Platycarya strobilacea and P. longipes. Previous information from species distribution models, fossil pollen data and genetic data based on chloroplast DNA (cpDNA) were integrated with newly obtained genetic data from the two putative species. We used both cpDNA (psbA-trnH and trnL-F intergenic spacers, including a partial trnL gene sequence) and nuclear markers. The latter included sequences of the internal transcribed spacer region (ITS1–5.8S–ITS2) of the nuclear ribosomal DNA and random genomic single nucleotide polymorphisms. Using these nuclear genetic markers, we found interspecific genetic divergence fitting with the ‘two species’ scenario and geographically structured intraspecific variation. Using cpDNA markers, we also found geographically structured intraspecific variation. Despite deep inter- and intraspecific genetic divergence, we detected genetic admixture in southwest China. Overall, our findings of genetic divergence within Platycarya support the hypothesis of allopatric speciation. However, episodes of population interconnection were identified, at least in southwest China, suggesting that the genus has had a dynamic population history. 相似文献
9.
David C. Samuels Chun Li Bingshan Li Zhuo Song Eric Torstenson Hayley Boyd Clay Antonis Rokas Tricia A. Thornton-Wells Jason H. Moore Tia M. Hughes Robert D. Hoffman Jonathan L. Haines Deborah G. Murdock Douglas P. Mortlock Scott M. Williams 《PLoS genetics》2013,9(11)
Mitochondrial DNA (mtDNA) variation can affect phenotypic variation; therefore, knowing its distribution within and among individuals is of importance to understanding many human diseases. Intra-individual mtDNA variation (heteroplasmy) has been generally assumed to be random. We used massively parallel sequencing to assess heteroplasmy across ten tissues and demonstrate that in unrelated individuals there are tissue-specific, recurrent mutations. Certain tissues, notably kidney, liver and skeletal muscle, displayed the identical recurrent mutations that were undetectable in other tissues in the same individuals. Using RFLP analyses we validated one of the tissue-specific mutations in the two sequenced individuals and replicated the patterns in two additional individuals. These recurrent mutations all occur within or in very close proximity to sites that regulate mtDNA replication, strongly implying that these variations alter the replication dynamics of the mutated mtDNA genome. These recurrent variants are all independent of each other and do not occur in the mtDNA coding regions. The most parsimonious explanation of the data is that these frequently repeated mutations experience tissue-specific positive selection, probably through replication advantage. 相似文献
10.
Hai Hu Hong Li Feng Jiao Ting Han Meng Zhuo Jiujie Cui Yixue Li Liwei Wang 《Journal of hematology & oncology》2017,10(1):158