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111.
目的:研究大豆卵磷脂的抗疲劳及抗氧化作用。方法:小鼠经口给予大豆卵磷脂30天后,采用负重游泳实验,观察记录小鼠游泳死亡时间;检测血清尿素氮、肝糖原;测定血清和肝匀浆超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GSH—Px)活力、丙二醛(MDA)含量。结果:给予大豆卵磷脂后,与对照组相比,实验组小鼠负重游泳时间明显延长,肝糖原消耗量减少,降低运动后血清尿素氮水平(P〈0.05);升高小鼠血清和肝匀浆SOD活性及GSH-Px活力,降低MDA的含量(P〈0.05)。结论:大豆卵磷脂具有抗疲劳和抗氧化作用。 相似文献
112.
Down-regulation of light-saturated photosynthesis (Asat) at elevated atmospheric CO2 concentration, [CO2], has been demonstrated for many C3 species and is often associated with inability to utilize additional photosynthate and/or nitrogen limitation. In soybean, a nitrogen-fixing species, both limitations are less likely than in crops lacking an N-fixing symbiont. Prior studies have used controlled environment or field enclosures where the artificial environment can modify responses to [CO2]. A soybean free air [CO2] enrichment (FACE) facility has provided the first opportunity to analyze the effects of elevated [CO2] on photosynthesis under fully open-air conditions. Potential ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) carboxylation (Vc,max) and electron transport through photosystem II (Jmax) were determined from the responses of Asat to intercellular [CO2] (Ci) throughout two growing seasons. Mesophyll conductance to CO2 (gm) was determined from the responses of Asat and whole chain electron transport (J) to light. Elevated [CO2] increased Asat by 15–20% even though there was a small, statistically significant, decrease in Vc,max. This differs from previous studies in that Vc,max/Jmax decreased, inferring a shift in resource investment away from Rubisco. This raised the Ci at which the transition from Rubisco-limited to ribulose-1,5-bisphosphate regeneration-limited photosynthesis occurred. The decrease in Vc,max was not the result of a change in gm, which was unchanged by elevated [CO2]. This first analysis of limitations to soybean photosynthesis under fully open-air conditions reveals important differences to prior studies that have used enclosures to elevate [CO2], most significantly a smaller response of Asat and an apparent shift in resources away from Rubisco relative to capacity for electron transport.Abbreviations FACE Free air [CO2] enrichment - Rubisco Ribulose-1,5-bisphosphate carboxylase/oxygenase - RuBP Ribulose-1,5-bisphosphate - SoyFACE Soybean free air [CO2] enrichment - VPD Vapor pressure deficit 相似文献
113.
Wang KJ Takahata Y Kono Y Kaizuma N 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,112(1):66-71
Soybean Kunit trypsin inhibitor (SKTI) has several polymorphic types. Of these SKTI, there are large differences of nine amino acid substitutions between Tia and Tib. So far no transitional type between them has been found. A novel transitional intermediate variant between Tia and Tib was detected in 11 lines from 720 Japanese wild soybeans (Glycine soja Sieb. & Zucc.). This variant showed identical electrophoretic mobility to Tib in the Davis system polyacrylamide gel electrophoresis (PAGE), but higher electric points than other SKTI proteins (Tia, Tib, Tic) in isoelectric focusing PAGE. The genetic analysis of SKTI in F2 seeds from a cross between the novel variant type and Tib showed that this variant type is inherited as codominant alleles in a multiple allelic system at an SKTI locus. This variant also showed inhibitory activity to trypsin. We propose the genetic symbol Ti
b
i5 for this novel variant. The sequence analysis of Tib
i5 revealed that six nucleotides were different between Tib
i5 and Tia, and the nucleotides of these mutated positions were identical to Tib. This causes substitution of five amino acids at the residue position 62 (Tyr→Phe), 74 (Ser→Arg), 114 (Met→Val), 120 (Leu→Ile) and 137 (Pro→Thr). These substitutive amino acids are completely in accord with the amino acids of Tib, showing that Tib
i5 is an intermediate between Tia and Tib types. Tib
i5 type is widely distributed throughout seven separate areas from northeast to southwest Japan with a 1.5% frequency of total materials examined. This indicated that Tib
i5 type did not originate from a recent mutation event, but had spread in wild soybean from ancient times. 相似文献
114.
Saski C Lee SB Daniell H Wood TC Tomkins J Kim HG Jansen RK 《Plant molecular biology》2005,59(2):309-322
Lack of complete chloroplast genome sequences is still one of the major limitations to extending chloroplast genetic engineering
technology to useful crops. Therefore, we sequenced the soybean chloroplast genome and compared it to the other completely
sequenced legumes, Lotus and Medicago. The chloroplast genome of Glycine is 152,218 basepairs (bp) in length, including a pair of inverted repeats of 25,574 bp of identical sequence separated by
a small single copy region of 17,895 bp and a large single copy region of 83,175 bp. The genome contains 111 unique genes,
and 19 of these are duplicated in the inverted repeat (IR). Comparisons of Glycine, Lotus and Medicago confirm the organization of legume chloroplast genomes based on previous studies. Gene content of the three legumes is nearly
identical. The rpl22 gene is missing from all three legumes, and Medicago is missing rps16 and one copy of the IR. Gene order in Glycine, Lotus, and Medicago differs from the usual gene order for angiosperm chloroplast genomes by the presence of a single, large inversion of 51 kilobases
(kb). Detailed analyses of repeated sequences indicate that many of the Glycine repeats that are located in the intergenic spacer regions and introns occur in the same location in the other legumes and
in Arabidopsis, suggesting that they may play some functional role. The presence of small repeats of psbA and rbcL in legumes that have lost one copy of the IR indicate that this loss has only occurred once during the evolutionary history
of legumes. 相似文献
115.
The actions of pepsin and the admixture of pepsin and Monascus pilosus carboxypeptidase 1 (MpiCP-1) on the hydrolysis of soybean protein were studied. The results showed that the pepsin hydrolyzate
of soybean protein was much more bitter and contained relatively smaller amounts of total free amino acids than the hydrolyzate
obtained with the admixture of pepsin and MpiCP-1. In addition, hydrophilic and hydrophobic amino acids were present in almost
equal proportions in the pepsin hydrolyzate, while mainly hydrophobic amino acids made up the hydrolyzate obtained with the
admixture of pepsin and MpiCP-1. These results suggest that MpiCP-1 suppresses and reverses the development of the bitterness
taste that results from the pepsin hydrolysis of soybean protein by releasing mainly hydrophobic amino acids from the C-termini
of the bitter components. 相似文献
116.
PM2, a group 3 LEA protein from soybean, and its 22-mer repeating region confer salt tolerance in Escherichia coli 总被引:7,自引:0,他引:7
To have knowledge of the effect of soybean PM2 protein in protecting dehydrated cells and its functional region, PM2 cDNA was isolated from soybean immature seeds. The recombinants expressing full-length PM2, truncated polypeptides of PM2A (aa 1-262) or PM2B (aa 129-262, 22-mer repeating region), or artificial polypeptide PM2C (duplication of 22-mer repeating region) were constructed. By using SDS-PAGE and mass spectrometry approaches, these fusion polypeptides were identified and proved to be hydrophilic and heat-stable. Spot assays of BL/PM2 and BL/pET28 (as control) showed that protein PM2 increased salt tolerance (500 mM NaCl or 500 mM KCl) of Escherichia coli, rather than osmotic tolerance (1100 mM sorbitol). In addition, comparing the survival ratios of the transformants under 500 mM NaCl or 500 mM KCl stresses, the results showed that: (1) the survival ratios of BL/PM2 and BL/PM2B were quite similar, both showing much higher values than those of BL/pET28. (2) The survival ratios of BL/PM2C were much higher than those of BL/PM2, BL/PM2A, and BL/PM2B. This provides the first experimental evidence that PM2 polypeptide enhances salt tolerance of E. coli cells, and the 22-mer repeat region is an important functional region. 相似文献
117.
Djebali W Zarrouk M Brouquisse R El Kahoui S Limam F Ghorbel MH Chaïbi W 《Plant biology (Stuttgart, Germany)》2005,7(4):358-368
The effects of cadmium (Cd) uptake on ultrastructure and lipid composition of chloroplasts were investigated in 28-day-old tomato plants (Lycopersicon esculentum var. Ibiza F1) grown for 10 days in the presence of various concentrations of CdCl2. Different growth parameters, lipid and fatty acid composition, lipid peroxidation, and lipoxygenase activity were measured in the leaves in order to assess the involvement of this metal in the generation of oxidative stress. We first observed that the accumulation of Cd increased with external metal concentration, and was considerably higher in roots than in leaves. Cadmium induced a significant inhibition of growth in both plant organs, as well as a reduction in the chlorophyll and carotenoid contents in the leaves. Ultrastructural investigations revealed that cadmium induced disorganization in leaf structure, essentially marked by a lowered mesophyll cell size, reduced intercellular spaces, as well as severe alterations in chloroplast fine structure, which exhibits disturbed shape and dilation of thylakoid membranes. High cadmium concentrations also affect the main lipid classes, leading to strong changes in their composition and fatty acid content. Thus, the exposure of tomato plants to cadmium caused a concentration-related decrease in the fatty acid content and a shift in the composition of fatty acids, resulting in a lower degree of fatty acid unsaturation in chloroplast membranes. The level of lipid peroxides and the activity of lipoxygenase were also significantly enhanced at high Cd concentrations. These biochemical and ultrastructural changes suggest that cadmium, through its effects on membrane structure and composition, induces premature senescence of leaves. 相似文献
118.
On the structure and synthesis of neuroprotectin D1, a novel anti-inflammatory compound of the docosahexaenoic acid family 总被引:1,自引:0,他引:1
Butovich IA 《Journal of lipid research》2005,46(11):2311-2314
Potato tuber lipoxygenase was shown to convert 17(S)-hydro(pero)xydocasahexaenoic acid in 10,17(S)-dihydro(pero)xydocosahexa-4Z,7Z,11E,13Z,15E,19Z-enoic acid [10,17(S)-diHDHA] which was formed apparently through a double lipoxygenation mechanism. No traces of 10,17(S)-dihydro(pero)xydocosahexa-4Z,7Z,11E,13E,15Z,19Z-enoic acid were found among the reaction products. It is very likely that a described earlier "neuroprotectin D1" [or "10,17(S)docosatriene"], a novel and potent anti-inflammatory compound derived from docosahexaenoic acid, was, in fact, 10,17(S)-dihydroxydocosahexa-4Z,7Z,11E,13Z,15E,19Z-enoic acid formed through a double lipoxygenation mechanism instead of a previously thought epoxidation/isomerization mechanism. 相似文献
119.
Tietge UJ Pratico D Ding T Funk CD Hildebrand RB Van Berkel T Van Eck M 《Journal of lipid research》2005,46(8):1604-1614
Group IIA secretory phospholipase A2 (sPLA2) is an acute-phase protein mediating decreased plasma HDL cholesterol and increased atherosclerosis. This study investigated the impact of macrophage-specific sPLA2 overexpression on lipoprotein metabolism and atherogenesis. Macrophages from sPLA2 transgenic mice have 2.5 times increased rates of LDL oxidation (thiobarbituric acid-reactive substances formation) in vitro (59 +/- 5 vs. 24 +/- 4 nmol malondialdehyde/mg protein; P < 0.001) dependent on functional 12/15-lipoxygenase (12/15-LO). Low density lipoprotein receptor-deficient (LDLR-/-) mice were transplanted with bone marrow from either sPLA2 transgenic mice (sPLA2--> LDLR-/-; n = 19) or wild-type C57BL/6 littermates (C57 BL/6-->LDLR-/-; n = 19) and maintained for 8 weeks on chow and then for 9 weeks on a Western-type diet. Plasma sPLA2 activity and plasma lipoprotein profiles were not significantly different between sPLA2-->LDLR-/- and C57BL/6-->LDLR-/- mice. Aortic root atherosclerosis was increased by 57% in sPLA2-->LDLR-/- mice compared with C57BL/6-->LDLR-/- controls (P < 0.05). Foam cell formation in vitro and in vivo was increased significantly. Urinary, plasma, and aortic levels of the isoprostane 8,12-iso-iPF2alpha-VI and aortic levels of 12/15-LO reaction products were each significantly higher (P < 0.001) in sPLA2-->LDLR-/- compared with C57BL/6-->LDLR-/- mice, indicating significantly increased in vivo oxidative stress in sPLA2--> LDLR-/-. These data demonstrate that macrophage-specific overexpression of human sPLA2 increases atherogenesis by directly modulating foam cell formation and in vivo oxidative stress without any effect on systemic sPLA2 activity and lipoprotein metabolism. 相似文献
120.
Maccarrone M Piccirilli S Battista N Del Duca C Nappi G Corasaniti MT Finazzi-Agrò A Bagetta G 《Journal of neurochemistry》2004,89(5):1293-1300
Human immunodeficiency virus type-1 coat glycoprotein gp120 causes delayed apoptosis in rat brain neocortex. Here, we investigated the possible role of the endocannabinoid system in this process. It is shown that gp120 causes a time-dependent increase in the activity and immunoreactivity of the anandamide (AEA)-hydrolyzing enzyme fatty acid amide hydrolase (FAAH), paralleled by increased activity of the AEA membrane transporter and decreased endogenous levels of AEA. The AEA-synthesizing phospholipase D and the AEA-binding receptors were not affected by gp120. None of the changes induced by gp120 in the cortex were induced by bovine serum albumin, nor were they observed in the hippocampus of the same animals. Also, the activity of 5-lipoxygenase, which generates AEA derivatives able to inhibit FAAH, decreased down to approximately 25% of the control activity upon gp120 treatment, due to reduced protein level ( approximately 45%). In addition, the FAAH inhibitor methyl-arachidonoyl fluorophosphonate significantly reduced gp120-induced apoptosis in rat brain neocortex, whereas selective blockers of AEA membrane transporter or of AEA-binding receptors were ineffective. Taken together, these results suggest that gp120, by activating FAAH, decreases endogenous levels of AEA, and the latter effect seems instrumental in the execution of delayed neuronal apoptosis in the brain neocortex of rats. 相似文献