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981.
Y. C. Qi W. Q. Liu L. Y. Qiu S. M. Zhang L. Ma H. Zhang 《Russian Journal of Plant Physiology》2010,57(2):233-240
The Suaeda salsa glutathione S-transferase gene (GST) was introduced into arabidopsis under the control of the cauliflower mosaic virus 35S
promoter. Transformants were selected for their ability to grow on medium containing kanamycin. Southern and northern blot
analyses confirmed that GST was transferred into the arabidopsis genome, and the GST and GPX activities in transgenic plants
(GT) were much higher than in wild-type plants (WT). There were no obvious morphological or developmental differences between
transgenic and wild-type plants. One transgenic homozygous line (GT6–8) and WT plants were evaluated for salt tolerance and gene expression. Seed germination and seedling salt tolerance were improved
after overexpression of GST in arabidopsis; the photosynthesis rate and the fresh weight of the GT6–8 line were distinctly higher than those of WT plants after NaCl treatment. Glutathione content increased substantially in
salt-stressed arabidopsis plants of both genotypes, and the glutathione pool in GT6–8 plants was more oxidized than in WT plants under both control and stressful conditions. The MDA content, an indicator of
lipid peroxidation, increased in WT plants but was not affected distinctly in GT6–8 seedlings after NaCl treatment. Results from different tests indicated that the expression of the GST gene promoted a higher
level of salt tolerance in vivo in transgenic arabidopsis plants. 相似文献
982.
Pang Y Liu J Wu J Li G Wang R Su Y He P Zhu X Yan D Zhu B 《Bioconjugate chemistry》2010,21(11):2093-2102
A series of novel long-chain hyperbranched poly(ethylene glycol)s (LHPEGs) with biodegradable connections were designed and synthesized in one pot through proton-transfer polymerization using PEG and commercial glycidyl methacrylate as monomers and potassium hydride as catalyst. The LHPEGs were hydrolyzed at neutral pH resulting in the decrease of molecular weights. In vitro evaluation demonstrated that LHPEGs were biocompatible and displayed negligible hemolytic activity. The efficient cellular uptake of LHPEGs was confirmed by flow cytometry and confocal laser scanning microscopy. Moreover, conjugation of a model hydrophobic anticancer drug methotrexate to LHPEGs inhibited the proliferation of a human cervical carcinoma Hela cell line. MTT assay indicated that the conjugated methotrexate dose required for 50% cellular growth inhibition against Hela cells was 20 μg/mL. By combining the advantages of long-chain hyperbranched structure and PEG, LHPEG provides a promising drug carrier for therapeutic fields. 相似文献
983.
Mao-feng Yue Ren-chao Zhou Ye-lin Huang Guo-rong Xin Su-hua Shi Li Feng 《Journal of Plant Biology》2010,53(2):165-171
High levels of genetic variation enable species to adapt to changing environments and provide plant breeders with the raw
materials necessary for artificial selection. In the present study, six AFLP primer pairs were used to assess the genetic
diversity of Desmodium triflorum (L.) DC. from 12 populations in South China. A high percentage of polymorphic loci (P = 76.16%) and high total gene diversity (H
T = 0.310) were found, indicating that the genetic diversity of D. triflorum is high at the species level. Genetic diversity was also relatively high at the population level (P = 55.85%, H
e = 0.230). The coefficient of gene differentiation among populations (G
ST) was 0.255, indicating that while most genetic diversity resided within populations, there was also considerable differentiation
among populations. AMOVA also indicated 24.29% of the total variation to be partitioned among populations (ΦST = 0.243). UPGMA clustering analysis based on genetic distances showed that the 12 populations could be separated into three
subgroups: an eastern, a western, and a central-southern subgroup. However, a Mantel test revealed no significant correlation
(r = 0.286, p = 0.983) between the geographical distances and genetic distances separating these populations; mountain barriers to gene
flow and human disturbance may have confounded these correlations. The present study has provided some fundamental genetic
data that will be of use in the exploitation of D. triflorum. 相似文献
984.
985.
Xiuli Wang Xiangying Meng Bin Song Xuemei Qiu Haiying Liu 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2010,155(3):327-330
Myostatin (MSTN) is a member of the transforming growth factor-β superfamily which negatively regulates growth of muscle tissue. In this study, 103 cultivated Chlamys farreri individuals were screened for polymorphisms in the MSTN gene using PCR-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing methods. Two mutations were found: A/G at position 327 in exon 2, which caused an amino acid change from Thr to Ala (Thr305Ala), and C/T at position 289 in exon 3, which caused an amino acid change from Cys to Arg (Cys422Arg). One way ANOVA of the SNPs and growth traits showed that genotype GG of primer M5 had significantly higher body mass, soft-tissue mass, adductor muscle mass, shell length, shell height, absolute growth rate of shell height and body mass than those of genotype AG and AA (P < 0.05). Genotype frequencies of genotype AA, AG and GG were 68.94%, 27.18% and 3.88%, respectively. The results present evidence that the C. farreri MSTN gene may be selected as a candidate gene for these growth traits. 相似文献
986.
XueFeng Chen ShiRu Jia SiJun Yue Ning Wang ChengTao Li Yue Wang 《Journal of applied phycology》2010,22(3):341-347
Nostoc flagelliforme was cultivated on three solid bed-materials which have different wettability. The results show that the wettability of solid
bed-materials is very important to the need for water in N. flagelliforme, and also greatly affects photosynthetic activity, polysaccharide secretion and the morphology of the cells. Glass residue
has the best wettability, followed by sand, and then nylon6 (PA6). We show that only sand is suitable for the growth of N. flagelliforme. When cultivated on sand for 100 days, the cells maintained a typical rosary-like shape. On glass residue, two to three vegetative
cells formed a group with slime. On PA6, cells were in the form of loose group with slimes. N. flagelliforme is applicable to desert control as it cannot only grow on the sand, but also adhere to sand to form a biological crust. 相似文献
987.
Laccase, a so-called “blue-copper” oxidase, is able to oxidize a variety of organic compounds. Sol–gel derived silica glasses
are frequently adopted as an immobilization method to improve the stability of enzymes and make them reusable. In this study,
immobilization conditions were optimized to achieve improved embedding results. The thermal stability, reaction stability
and storage stability were improved with the immobilized enzyme when compared to the free enzyme. 2,4-Dichlorophenol (DCP)
and 2,4,6-trichlorophenol (TCP) were chosen as model compounds. The treatment of chlorophenols (CPs) by immobilized laccase
demonstrated excellent removal and response stability. The affinity of TCP for immobilized laccase was higher than that of
DCP. This finding leads to different removal efficiencies under variable conditions (reaction time, initial concentration,
dosage of immobilized laccase and removal rate in mixed solution). By fitting the experimental data with the diffusion model
of the degradation process, the degradation of CPs by immobilized laccase matches an intraparticle diffusion-controlled model. 相似文献
988.
989.
990.
Wei Li Yi-Min Tao Yun Tang Xue-Jun Xu Jie Chen Wei Fu Xing-Hai Wang Bo Chao Wei Sheng Qiong Xie Zhui-Bai Qiu Jing-Gen Liu 《Bioorganic & medicinal chemistry letters》2010,20(1):418-421
Unexpected substituent on the well-known morphine skeleton is described to be account for highly selective and potent μ opioid ligands, which is strongly connected to substituted aromatic groups on this omitted 8α-position. 相似文献