工业大麻秸秆乙醇提取物对大豆胞囊线虫生理生化代谢的影响

为明确工业大麻秸秆乙醇提取物抑制大豆胞囊线虫的作用机理,采用浸泡法研究其对大豆胞囊线虫体内的总糖、甘油和蛋白质含量以及解毒酶活性等生理生化指标的影响,结果表明:二龄幼虫虫体内总糖含量和甘油含量随乙醇提取物处理时间的延长呈上升趋势,处理24 h时分别较对照升高了96.2％和33.5％,达极显著差异;可溶性蛋白含量随处理时...     

微囊藻毒素对鲢鱼肝脏GST和CYP7A1基因表达的影响

为探究微囊藻毒素(MC)对鲢鱼肝脏谷胱甘肽S转移酶(GST)和胆固醇7α-羟化酶(CYP7A1)基因表达的影响,克隆了鲢鱼肝脏GST和CYP7A1基因的部分c DNA片段,并对饲养密度为1.3×108cell/L的有毒和无毒两种铜绿微囊藻水体中第2 d、第4 d和第6 d的鲢鱼肝脏取样,通过RT-PCR与Q-PCR技术分析肝脏GST和CYP7A1基因在MC影响下不同时间点的表达情况。结果显示,有毒铜绿微囊藻水体中鲢鱼肝脏GST相对表达量在第6 d显著下降,说明GST基因在第6 d时在MC解毒过程中开始发挥作用;鲢鱼CYP7A1相对表达量自第2 d开始显著下调并随时间延续维持在一个较低的水平,说明MC作用下CYP7A1表达受到抑制,可能对胆汁酸合成造成影响。为进一步研究鱼类微囊藻毒素去毒基因以及抑制对MC转运和吸收的关键基因提供依据。     

生物调控剂对大蒜的抗性影响

文章在生物测定和田间实验方法的基础上,利用生化分析的方法研究了生物调控剂对大蒜抗性的作用。结果表明,用一定浓度的生物调控剂处理大蒜,能明显调节大蒜的生长发育,叶绿素含量提高,根系活力增强,大蒜辣素含量和谷胱甘肽含量随处理浓度的增加呈递增趋势,谷胱甘肽转移酶活性和过氧化氢酶活性增强。     

安全剂双苯恶唑酸对水稻精恶唑禾草灵药害的解毒效应

为了解安全剂双苯恶唑酸缓解除草剂精恶唑禾草灵对水稻药害的效果,通过温室水培和盆栽法研究双苯恶唑酸对水稻精恶唑禾草灵药害的解毒效果,并对其解毒机制进行初步探讨。结果表明:水稻萌发期,粳稻和籼稻在0.25、0.5、1μg/m L精恶唑禾草灵处理下,解毒效果最好的安全剂添加比例分别为1∶1、1∶5、1∶5,粳稻株高、胚根长的抑制率比精恶唑禾草灵单独使用分别降低18.07、37.50,26.56、34.94,41.30、37.50个百分点,籼稻株高、胚根长的抑制率分别降低23.31、42.33,27.22、34.91,46.76、31.14个百分点;水稻两至三叶期,粳稻和籼稻在25、100μg/m L精恶唑禾草灵处理下,谷胱甘肽-S-转移酶(GST)和乙酰辅酶A羧化酶(ACCase)活性最高的安全剂添加比例均为1∶1,此时粳稻的GST活性和ACCase活性比精恶唑禾草灵单独使用分别增加42.21%和65.63%、46.72%和140.43%,籼稻的GST活性和ACCase活性比精恶唑禾草灵单独使用分别增加52.18%和105.71%、55.55%和169.52%。安全剂双苯恶唑酸提高了精恶唑禾草灵处理后水稻幼苗中GST、ACCase活性,减轻了精恶唑禾草灵对水稻的伤害,为水稻生产中通过添加双苯恶唑酸降低精恶唑禾草灵对水稻的药害提供了依据。     

MBF2转录调控小菜蛾谷胱甘肽S-转移酶代谢氯虫苯甲酰胺的功能

【目的】探究转录调控因子MBF2 (multiprotein bridging factor 2)调控小菜蛾（Plutella xylostella）体内谷胱甘肽S-转移酶（glutathione S-transferase,GST）的功能,及其在小菜蛾抗氯虫苯甲酰胺中的作用,为阐明小菜蛾对氯虫苯甲酰胺的解毒代谢机制提供理论依据。【方法】采用浸叶法测定敏感（SS）、广东连州（LZ）、云南通海（TH）3个小菜蛾种群对氯虫苯甲酰胺的抗性水平,酶动力学法测定3个种群的GST活性;使用实时荧光定量PCR(RT-qPCR)分析MBF2在不同抗性种群小菜蛾中的表达差异;采用氯虫苯甲酰胺LC50诱导12 h,分析其对小菜蛾MBF2的诱导表达作用;应用RNA干扰（RNA interference,RNAi）技术研究MBF2对GST基因的调控作用,并测定沉默MBF2后小菜蛾的GST活性;结合沉默后小菜蛾对药剂的敏感性变化,验证MBF2在小菜蛾抗氯虫苯甲酰胺中的作用。【结果】两个抗性种群（TH和LZ）相较SS种群分别达到了中抗及高抗的水平,TH和LZ抗性倍数分别为54.27和289.58;TH和LZ小菜蛾...     

Cloning of a rice tau class GST isozyme and characterization of its substrate specificity

The GST cDNA was successfully cloned from an Oryza sativa cDNA library by PCR using oligonucleotide primers based on the OsGSTU5 (GenBank Accession No. AF309377) sequence. The cDNA was composed of a 687-bp open reading frame encoding for 228 amino acids. The deduced amino acid sequence of this gene shared over 60% sequence identity with the sequences of the tau class ZmGSTU6 and ZmGSTU19. This gene was expressed in Escherichia coli with the pET vector system and the gene product was purified to homogeneity by GSH-Sepharose affinity column chromatography. The expressed OsGSTU5 formed a homo-dimer composed of 25 kDa subunit and its pI value was approximately 7.5. The OsGSTU5 displays high activities towards 1-chloro-2,4-dinitrobenzene and 1,2-epoxy-3-(p-nitrophenoxy)propane. The activity of the OsGSTU5 was significantly inhibited by hematin and ethacrynic acid. The OsGSTU5 shows the highest activity towards chloro-s-triazine and acetanilide herbicides.     

Post-harvest Regeneration of Lowland Black Spruce Forests in Northeastern Ontario

Success of natural regeneration has been a concern since the introduction of heavy machinery in harvesting. The objective was to compare the effect of three operational harvest methods careful logging around advanced growth (CLAAG), group seed tree (GST), and group seed tree followed by shearblading site preparation (SHE) on natural regeneration in the Clay Belt region of Ontario. A total of 30 stands, 562 cluster sample plots, were surveyed. Total density of black spruce regeneration did not differ, but height structure of black spruce regeneration did among harvest methods. The CLAAG method resulted in highest total regeneration density of other conifers. Decreasing density of other conifers from the CLAAG to GST to SHE sites indicated that the CLAAG method protected advance regeneration as expected and the SHE method removed advance regeneration in the path of the shearing blade. Both black spruce and other conifer regeneration densities increased with increasing time since harvest. Stocking of black spruce, all conifers, or all tree species did not differ significantly among harvest methods, nor did it change with time since harvest. Stocking was nonlinearly related to regeneration density. Models developed in this study predict that full stocking (i.e., 60%) can be reached based on regeneration density of 5000 stems per ha regardless of crop species choice preference. However, the existing stocking criterion for assessing black spruce regeneration may be problematic.     

Fenitrothion toxicity in triatoma infestans synergized by quercetin or thymol blue

Quercetin and thymol blue were shown to synergize the toxicity of fenitrothion to Triatoma infestans with synergistic ratios of 1.89 and 2.65 respectively. These synergistic ratios were statistically significant at P<0.05. Both compounds inhibited glutathione S-transferases (GST) in vitro, with pI₅₀ values of 6.1 and 5.1 respectively. Quercetin or thymol blue caused in-vivo GST inhibition without affecting non-specific esterase (NSE) or acetylcholinesterase (AChE) activity. Incubation of [¹⁴C]fenitrothion with T. infestans or rabbit liver GST produced desmethylfenitrothion as the major metabolite, which was specifically diminished in the presence of 0.3 mM quercetin. [¹⁴C]Fenitrothion toxicokinetics study showed a significant decrease (P<0.05) in radioactivity due to polar metabolites when insects were pre-treated with quercetin. These facts suggest that both assayed chemicals may be active in synergizing fenitrothion toxicity due to their ability to prevent the detoxification of organophosphorus insecticides by GSH conjugation. © 1999 Society of Chemical Industry     

棉花恢复系的恢复力与花药谷胱甘肽S转移酶活性的关系

转gst基因棉花恢复系"浙大强恢"克服了传统恢复系的恢复力不够强的缺陷,用此种恢复系配制的杂种F1,其花粉育性强,杂种优势明显.进一步研究的结果表明:在造孢细胞增殖、小孢子减数分裂和花粉成熟3个时期,转基因恢复系花药中谷胱甘肽S转移酶(GST)活性比受体恢复系花药中的都有极显著提高.与受体恢复系配制的F1相比,转基因恢复系     

能源甜菜BvGST基因在大肠杆菌体内对镉逆境的应答特性分析

为了进一步研究BvGST基因(LOC104898671)在能源甜菜耐受重金属镉逆境胁迫过程中的功能,明确其在细胞解毒镉离子中的作用和应答特性,本研究以780016B/12优为植物材料,通过RT-PCR的方法将BvGST基因克隆并构建于大肠杆菌原核表达载体pEASY-Blunt E1上,并转化到大肠杆菌BL21中。SDS-PAGE电泳表明,通过1 mmol/L IPTG诱导,在重组菌BL21总蛋白的25.9 kDa左右的位置上,获得了大肠杆菌his tag-BvGST的融合蛋白。当施加0.5 mmol/L CdCl2逆境胁迫后,表达BvGST蛋白的重组菌表现出优于对照菌的生长状态;与此同时,大量表达BvGST的大肠杆菌体内的GST酶活性也要远高于对照。这说明,能源甜菜BvGST基因通过在E. coli体内大量表达高活性的谷胱甘肽转移酶,来解毒细胞内由镉胁迫带来的氧化伤害,从而提高大肠杆菌的Cd耐受性。研究结果暗示了能源甜菜BvGST在镉逆境胁迫分子机制中发挥着重要作用。