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31.
Hongying Cui Yucheng Sun Jianwei Su Qin Ren Chuanyou Li Feng Ge 《Arthropod-Plant Interactions》2012,6(3):425-437
The effect of elevated O3 on tomato plants of three different genotypes (wild-type, a jasmonic acid (JA) defense-enhanced genotype (35S) and a JA-deficient genotype (spr2)) grown in association with the whitefly Bemisia tabaci Gennadius biotype B was examined in the field in open-top chambers. We experimentally tested the hypothesis that elevated O3 tends to reduce the nutrition of tomato plants, and to increase the SA-dependent pathway defenses and the secondary metabolites, and therefore decrease the population fitness of the whitefly. The results show that for all three tomato genotypes, elevated O3 reduced the soluble sugars and free amino acids, increased the phenylalanine ammonia-lyase enzyme activity and the accumulated salicylic acid (SA), and up-regulated the pathogenesis-related protein (PR1), which is commonly considered to be the whitefly-resistance gene product involved in SA-dependent defense. Elevated O3 did not affect the JA level in any of the three plant genotypes, but it increased the levels of some secondary metabolites, including total phenolics and condensed tannins. Elevated O3 prolonged the developmental time of whiteflies fed on the three plant genotypes, and it also reduced the fecundity and the intrinsic rate of increase of whiteflies fed on either the 35S or the wild-type plants. These results suggest that elevated O3 reduces the nutrition of tomato plants and enhances their SA content, relative PR mRNA expression and secondary metabolism, resulting in decreased fitness of whiteflies on these tomato plants. 相似文献
32.
Molecular insights into the antifungal mechanism of bacilysin 总被引:1,自引:0,他引:1
Tao?WangEmail author Xiao-huan?Liu Mian-Bin?WuEmail author Shun?Ge 《Journal of molecular modeling》2018,24(5):118
Bacilysin is one of the simplest antimicrobial peptides and has drawn great attention for its excellent performance against Candida albicans. In this study, the antifungal mechanism of bacilysin was investigated. The target enzyme glucosamine-6-phosphate synthase (GFA) was expressed heterologously in Escherichia coli and its inhibition by bacilysin and derivatives was studied. It was concluded that bacilysin could be hydrolyzed by a proteinase of C. albicans, and that the released product, anticapsin, then inhibited the aminotransferase activity of GFA. This result was verified by molecular simulation, and the interaction mode of anticapsin with GFA was detailed, which provides data for the development of novel antifungal drugs. Transport of bacilysin into fungal cells was also simulated and it was shown that bacilysin is more readily transported into cells than anticapsin. Thus, our findings support a mechanism whereby bacilysin is transported into fungal pathogens, hydrolyzed to anticapsin, which then inhibits GFA. 相似文献
33.
Ni-Na Ge Yong-Kai Wei Feng Zhao Xiang-Rong Chen Guang-Fu Ji 《Journal of molecular modeling》2014,20(7):1-9
Thanks to the advances in grid technologies, we are able to propose here an evolution of our molecular simulator that, when moving to larger systems, instead of reducing the granularity of the dynamical treatment (as is often done in molecular dynamics studies of such systems) exploits the extra power of the grid approach to the end of preserving the detailed nature of theatomistic formulation of the interaction. Key steps of such evolution are: (1) the assemblage of the interaction based on a composition of the ab initio intramolecular data and a portable parameterization of the intermolecular potential linking ab initio evaluation of intramolecular potentials and the partitioning of molecular polarizability; (2) the exploitation of an efficient coordinated porting and running of molecular dynamics codes on the European grid distributed computing infrastructure. As a prototype case study, the N-methylacetamide dimer in vacuo has been considered and the formation of possible conformers is analyzed. 相似文献
34.
Lin Xu Yong Zhang Zheng Shan Deng Liang Zhao Xiu Li Wei Ge Hong Wei 《Antonie van Leeuwenhoek》2013,103(3):559-565
During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01T contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01T (= ACCC 05747T = JCM 18337T) is designated as the type strain. 相似文献
35.
Ziqiang Ding Hongwei Duan Wenbo Ge Jianshu Lv Jianlin Zeng Wenjuan Wang Tian Niu Junjie Hu Yong Zhang Xingxu Zhao 《Animal Reproduction》2022,19(2)
Progesterone (P4) can participate in the development of female mammalian antral follicles through nuclear receptor (PGR). In this experiment, the differences of P4 synthesis and PGR expression in different developmental stages of sheep antral follicles (large > 5mm, medium 2-5mm, small < 2mm) were detected by enzyme-linked immunosorbent assay, immunohistochemistry, qRT-PCR and Western blotting. Secondly, sheep follicular granulosa cells were cultured in vitro. The effects of different concentrations of FSH and LH on P4 synthesis and PGR expression were studied. The results showed that acute steroid regulatory protein (StAR), cholesterol side chain lyase (P450scc) and 3β Hydroxysteroid dehydrogenase (3β-HSD) and PGR were expressed in antral follicles, and with the development of antral follicles in sheep, StAR, P450scc and the expression of 3β-HSD and PGR increased significantly. In vitro experiments showed that FSH and LH alone or together treatment could regulate P4 secretion and PGR expression in sheep follicular granulosa cells to varying degrees, hint P4 and PGR by FSH and LH, and LH was the main factor. Our results supplement the effects of FSH and LH on the regulation of P4 synthesis during follicular development, which provides new data for further study of steroid synthesis and function in follicular development. 相似文献
36.
Guo Zhao Xiaobing Gu Xinlun Lu Jinjin Pan Zhiqiang Duan Kunkun Zhao Min Gu Qingtao Liu Liang He Jian Chen Shengqiang Ge Yanhong Wang Sujuan Chen Xiaoquan Wang Daxin Peng Hongquan Wan Xiufan Liu 《PloS one》2012,7(9)
There has been multiple evidence that domestic poultry may act as a vessel for the generation of novel influenza A viruses. In this study, we have analyzed the evolution and pathogenicity of 4 H5N2 avian influenza viruses isolated from apparently healthy poultry from H5N1 virus endemic areas in China. Phylogenetic analysis revealed that two of these viruses, A/duck/Eastern China/1111/2011 (DK/EC/1111/11) and A/goose/Eastern China/1112/2011 (GS/EC/1112/11) were derived from reassortment events in which clade 2.3.4 highly pathogenic avian influenza (HPAI) H5N1 viruses acquired novel neuraminidase and nonstructural protein genes. Another two isolates, A/chicken/Hebei/1102/2010 (CK/HB/1102/10) and A/duck/Hebei/0908/2009 (DK/HB/0908/09), possess hemagglutinin (HA) gene belong to clade 7 H5 viruses and other genes from endemic H9N2 viruses, or from viruses of various subtypes of the natural gene pool. All of these H5N2 isolates bear characteristic sequences of HPAI virus at the cleavage site of HA, and animal experiments indicated that all of these viruses but DK/HB/0908/09 is highly pathogenic to chickens. In particular, DK/EC/1111/11 and GS/EC/1112/11 are also highly pathogenic to ducks and moderately pathogenic to mice. All of these 4 viruses were able to replicate in domestic ducks and mice without prior adaptation. The emergence of these novel H5N2 viruses adds more evidence for the active evolution of H5 viruses in Asia. The maintenance of the highly pathogenic phenotype of some of these viruses even after reassortment with a new NA subtypes, their ability to replicate and transmit in domestic poultry, and the pathogenicity in the mammalian mouse model, highlight the potential threat posed by these viruses to both veterinary and public health. 相似文献
37.
Lundin KE Ge R Svahn MG Törnquist E Leijon M Brandén LJ Smith CI 《Biomolecular engineering》2004,21(2):51-59
Peptide nucleic acid (PNA) is a DNA analog with broad biotechnical applications, and possibly also treatment applications. Its suggested uses include that of a specific anchor sequence for biologically active peptides to plasmids in a sequence-specific manner. Such complexes, referred to as Bioplex, have already been used to enhance non-viral gene transfer in vitro. To investigate how hybridization of PNAs to supercoiled plasmids would be affected by the binding of multiple PNA-peptides to the same strand of DNA, we have developed a method of quantifying the specific binding of PNA using a PNA labeled with a derivative of the fluorophore thiazole orange (TO). Cooperative effects were found at a distance of up to three bases. With a peptide present at the end of one of the PNAs, steric hindrance occurred, reducing the increase in binding rate when the distance between the two sites was less than two bases. In addition, we found increased binding kinetics when two PNAs binding to overlapping sites on opposite DNA strands were used, without the use of chemically modified bases in the PNAs. 相似文献
38.
The extinct new species,Chresmoda chikuni Zhang & Ge,sp.nov.is described from the Mid-Cretaceous amber from northem Myanmar.This amber insect exhibits a very peculiar combination of derived characters like strongly elongated,free coxa,non-clawed pretarsus.The type specimens are deposited in the Three Gorges Entomological Museum,Chongqing,China. 相似文献
39.
Increasing evidence suggests that dendritic cells (DCs) and oxidized low-density lipoprotein (ox-LDL) participate in atherosclerosis. However, few data on the molecular mechanisms of this process are available. To address this question, we used iTRAQ labeling followed by LC-MS/MS analysis to identify many proteins that changed markedly during the maturation of dendritic cells stimulated with ox-LDL. Among a total of 781 identified proteins, 93 were upregulated and 100 were downregulated. The major and significant changes in upregulated proteins were that ox-LDL not only affected the levels of intracellular cathepsins G, Z, D and S, but also significantly enhanced cathepsin S secretion by the treated cells. Our results may provide clues for a more comprehensive understanding the pathogenesis of atherosclerosis. 相似文献
40.