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1.
Hyalophora cecropia pupae were infected by Enterobacter cloacae C7-501 to induce antibacterial attacins for purification. The induction of attacins in immunized pupae was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Ion-exchange chromatography (IEC), hydrophobic interaction chromatography (HIC), and Rotofor® isoelectric focusing (ISEF) were applied to isolate attacins from the hemolymph. IEC separated attacins from most hemolymph proteins, but the fractions containing attacins also had other proteins of 20 and 64 kDa in length. In IEC, attacin was eluted with ~0.2 M NaCl. The best conditions for IEC were pH 9, flow rate of 2 mL/min, with step elution (0.025, 0.05, 0.075, 0.1, 0.2, 0.4 and 1.0 M NaCl). In HIC, most other proteins were eluted with the ammonium persulfate treatment. HIC isolated attacin proteins under hydrophobic conditions, at ~50% EtOH. However, the fraction with attacins also contained other proteins. The Rotofor® ISEF produced fractions containing attacins at isoelectric points ranging between 5.7 and 8.3. However, non-specific proteins were detected in the fraction samples, and the recovery of attacins was low. The purification efficiency of ISEF was lower than IEC and HIC. In this study, the expression of attacins was induced in H. cecropia pupae infected with E. cloacae C7-501, and attacins could be purified by IEC and ISEF. Overall, IEC provided better separation of attacins from the hemolymph of H. cecropia pupae immunized with E. cloacae bacteria than HIC and Rotofor® ISEF.  相似文献   
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Bacterial genome segregation and cell division has been studied mostly in bacteria harbouring single circular chromosome and low-copy plasmids. Deinococcus radiodurans, a radiation-resistant bacterium, harbours multipartite genome system. Chromosome I encodes majority of the functions required for normal growth while other replicons encode mostly the proteins involved in secondary functions. Here, we report the characterization of putative P-loop ATPase (ParA2) encoded on chromosome II of D. radiodurans. Recombinant ParA2 was found to be a DNA-binding ATPase. E. coli cells expressing ParA2 showed cell division inhibition and mislocalization of FtsZ-YFP and those expressing ParA2-CFP showed multiple CFP foci formation on the nucleoid. Although, in trans expression of ParA2 failed to complement SlmA loss per se, it could induce unequal cell division in slmAminCDE double mutant. These results suggested that ParA2 is a nucleoid-binding protein, which could inhibits cell division in E. coli by affecting the correct localization of FtsZ and thereby cytokinesis. Helping slmAminCDE mutant to produce minicells, a phenotype associated with mutations in the ‘Min’ proteins, further indicated the possibility of ParA2 regulating cell division by bringing nucleoid compaction at the vicinity of septum growth.  相似文献   
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Little is known about the effect of exercise training on the expression of adiponectin receptor genes in peripheral blood mononuclear cells (PBMCs). In this study, we investigated the effects of aerobic training on the expression of AdipoR1 and AidpoR2 mRNAs in PBMCs, whole body insulin sensitivity, and circulating adiponectins in men. Thirty young men were randomly assigned to either a control (n=15) or an exercise (n=15) group. Subjects assigned to the exercise group underwent a 12-week jogging and/or running programme on a motor-driven treadmill at an intensity of 60%-75% of the age-based maximum heart rate with duration of 40 minutes per session and a frequency of 5 days per week. Two-way mixed ANOVA with repeated measures was used to test any significant time-by-group interaction effects for the measured variables at p=0.05. We found significant time-by-group interaction effects for waist circumference (p=0.001), VO2max (p<0.001), fasting insulin (p=0.016), homeostasis model assessment for insulin resistance (HOMA-IR) (p=0.010), area under the curve (AUC) for insulin response during the 75-g oral glucose tolerance test (p=0.002), high-molecular weight (HMW) adiponectin (p=0.016), and the PBMC mRNA levels of AdipoR1 (p<0.001) and AdipoR2 (p=0.001). The exercise group had significantly increased mRNA levels of AdipoR1 and AdipoR2 in PBMCs, along with increased whole body insulin sensitivity and HMW adiponectin, decreased waist circumference, and increased VO2max compared with the control group. In summary, the current findings suggest that exercise training modulates the expression of AdipoR1 and AdipoR2 mRNAs in PBMCs, implying that manipulation of the expression of these genes could be a potential surrogate for lifestyle intervention-mediated improvements of whole body insulin sensitivity and glucose homeostasis.  相似文献   
5.
Low intensity resistance exercise (RE) with blood flow restriction (BFR) has gained attention in the literature due to the beneficial effects on functional and morphological variables, similar to those observed during traditional RE without BFR, while the effects of BFR on post-exercise hypotension remain unclear. The aim of the present study was to compare the blood pressure (BP) response of trained normotensive individuals to RE with and without BFR. In this cross-over randomized trial, eight male subjects (23.8 ± 4 years, 74 ± 3 kg, 174 ± 4 cm) completed two exercise protocols: traditional RE (3 x 10 repetitions at 70% one-repetition maximum [1-RM]) and low intensity RE (3 x 15 repetitions at 20% 1-RM) with BFR. Blood pressure measurements were performed after 15 min of seated rest (0), immediately after and 10 min, 20 min, 30 min, 40 min, 50 min and 60 min after the experimental sessions. Similar hypotensive effects for systolic BP (SBP) were observed for both protocols (P < 0.05) after exercise, with no differences between groups (P > 0.05) and no statistically significant difference for diastolic BP (P > 0.05). These results suggest that in normotensive trained individuals, both traditional RE and RE with BFR induce hypotension for SBP, which is important to prevent cardiovascular disturbances.  相似文献   
6.
The genetic diversity among 16 strains of Erwinia amylovora, chosen to represent different host plant origins and geographical regions, was investigated by RAPD analysis. One strain of Erwinia herbicola and one of Agrobacterium vitis were used as outgroups. Ninety-eight different RAPD fragments were produced by polymerase chain reaction amplification with six different 10-mer primers. RAPD banding profiles were found that enabled the Erw. amylovora strains to be distinguished from one another. Cluster analysis based on the number of RAPD fragments shared between strains showed that strains of Erw. amylovora isolated from subfamily Pomoideae formed a single group, whereas two strains from Rubus (subfamily Rosoideae) formed a second group. Two strains isolated from Asian pear on Hokkaido, Japan, formed a third group. Sets of RAPD fragments were identified that enabled each of the two host-range groups and one geographical region (Hokkaido) of Erw. amylovora strains to be unambiguously distinguished from one another and from the outgroups. This study shows that strains of Erw. amylovora exhibit genetic diversity detectable by RAPD analysis, and that molecular and statistical analysis of RAPD fragments can be used both to distinguish between strains and to determine relatedness between them.  相似文献   
7.
Accelerated solvent extraction (ASE) is an alternative sample extraction procedure for ochratoxin A in roasted coffee. ASE results are comparable to that of the modified Koch method, but required less sample preparation time. Furthermore, ASE gave higher quantitative values than other methods reported for extraction of ochratoxin A. In the end less harmful water could be used for extraction.  相似文献   
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Multiple models for Rosaceae genomics   总被引:5,自引:0,他引:5  
The plant family Rosaceae consists of over 100 genera and 3,000 species that include many important fruit, nut, ornamental, and wood crops. Members of this family provide high-value nutritional foods and contribute desirable aesthetic and industrial products. Most rosaceous crops have been enhanced by human intervention through sexual hybridization, asexual propagation, and genetic improvement since ancient times, 4,000 to 5,000 B.C. Modern breeding programs have contributed to the selection and release of numerous cultivars having significant economic impact on the U.S. and world markets. In recent years, the Rosaceae community, both in the United States and internationally, has benefited from newfound organization and collaboration that have hastened progress in developing genetic and genomic resources for representative crops such as apple (Malus spp.), peach (Prunus spp.), and strawberry (Fragaria spp.). These resources, including expressed sequence tags, bacterial artificial chromosome libraries, physical and genetic maps, and molecular markers, combined with genetic transformation protocols and bioinformatics tools, have rendered various rosaceous crops highly amenable to comparative and functional genomics studies. This report serves as a synopsis of the resources and initiatives of the Rosaceae community, recent developments in Rosaceae genomics, and plans to apply newly accumulated knowledge and resources toward breeding and crop improvement.  相似文献   
10.
A cDNA clone of the gene encoding attacin was used to construct three plasmid binary vectors in which attE was controlled by the cauliflower mosaic virus 35S promoter with duplicated upstream B domain (35S) (p35SAtt), 35S with the untranslated leader sequence of alfalfa mosaic virus RNA 4 (AMV) (p35SAMVAtt), and 35S with AMV and the signal peptide of pathogenesis-related protein 1b from tobacco (SP) (p35SAMVSPAtt), respectively. These plasmids and pLDB15 containing attE under the control of the potato proteinase inhibitor II (Pin2) promoter were used in Agrobacterium-mediated transformation of the apple scion cultivar `Galaxy' and the apple rootstock M.26 to enhance resistance to Erwinia amylovora, the bacterium that causes fire blight. The mean attacin content of transgenic lines containing attacin with AMV was three times higher than lines without AMV. Northern blots suggested that AMV functioned in apple as it does in other plant species by enhancing translation of attE mRNA. Transgenic `Galaxy' lines with attacin fused to SP had lower attacin content than lines without SP. In vitro assays indicated that attacin was partially degraded in the intercellular fluid of apple leaves. However, transgenic `Galaxy' lines transformed with attacin fused to SP had significantly less disease than those without SP suggesting that intercellularly secreted attacin is more effective in reducing E. amylovora infection than intracellularly localized attacin. A negative correlation was observed between attacin content and disease resistance in Pin2Att transgenic `Galaxy' lines following inoculation with E. amylovora, suggesting that attacin enhances resistance to fire blight.  相似文献   
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