非生物胁迫对盐生杜氏藻DsMPK转录、翻译和磷酸化修饰的影响

促有丝分裂活化蛋白激酶(Mitogen-activated protein kinase,MAPK或MPK)途径是在真核生物中广泛存在的调控多种生理过程的信号途径,在细胞增殖、分化、凋亡、生物和非生物胁迫等生理过程的调控中起着关键的作用.盐生杜氏藻(Dunaliella salina,盐藻)是目前世界上最耐盐的真核光合生物之一.在前期实验中,已发现盐藻MAPK(DsMPK)的表达受到低温和高盐胁迫的抑制.分析DsMPK在高温、低盐、氧化、紫外胁迫中的表达变化,发现DsMPK还受到氧化胁迫的抑制.进而分析DsMPK在高温、低盐、氧化、低温、高盐和紫外胁迫中翻译和磷酸化修饰的变化,发现除低盐胁迫外,在磷酸化修饰水平DsMPK同样受到各种非生物胁迫的抑制.在对不同生长阶段盐藻DsMPK磷酸化变化的分析中还发现,DsMPK的磷酸化水平与生长速率有一致性.各方面DsMPK的变化趋势说明其为一调控生长相关的MAPK.     

酶联免疫吸附法测定麻疯树核糖体失活蛋白

建立了一种检测麻疯树核糖体失活蛋白(Curcin)的简便、快速的酶联免疫吸附测定法(ELISA).ELISA条件优化试验结果显示:最佳条件为costar酶标板在紫外线下照射45 min后进行包被;抗原最适稀释度为1:640倍(2.5μg/mL);curcin抗血清最适稀释度为1:12 800倍;2%封闭用山羊血清封闭120 min;二抗最适稀释度为1:5 000倍.在此试验条件下检测curcin含量,得到回归方程y=31.722x+106.88,相关系数R2=0.993 3.Curcin浓度在0.08～11μg/mL之间,曲线呈良好的线性关系.本方法的最低检测限为0.08μg/mL.高、中、低3个浓度的添加回收率分别为95.56%、102.27%、98.40%,平均回收率为98.74%.板内和板间的平均变异系数分别为4.78%和6.71%.Curcin抗血清与2种大戟科同类蛋白均无交叉反应.利用本方法成功检测了麻疯树种仁及脱毒饼粕中的curcin含量.     

镉对瓯江彩鲤脏器组织蛋白质的氧化损伤作用

瓯江彩鲤(Cyprinus carpio var color)是浙江省大力推广的主要稻田养鱼鱼种,重金属污染对其生态毒理效应研究具有重要意义.针对镉胁迫瓯江彩鲤蛋白质氧化损伤效应,采用静态置换法,研究了0.412～2.059 mg·L-1浓度范围内的镉对瓯江彩鲤鳃、脑和肝脏组织蛋白质的氧化损伤作用.结果表明,瓯江彩鲤鳃...     

城市生活污水处理中剩余污泥处理技术探讨

分析了武汉市污水处理现状、剩余污泥的产量与处理技术概况,介绍了制备蛋白质泡沫灭火剂技术再利用剩余污泥的可行性。     

磷酸化蛋白质组学技术的发展及其在环境毒理研究中的应用

磷酸化修饰是蛋白质最主要的翻译后修饰形式之一,磷酸化蛋白质组学从整体上观察细胞或组织中磷酸化修饰的状态及其变化,为探讨药物刺激和环境应激下生物体受损的生物学过程提供新的视角.针对磷酸化蛋白质组学技术的发展以及其在环境毒理研究中的应用展开综述.首先,从磷酸化肽富集、磷酸化蛋白的鉴定和磷酸化位点的预测、定量磷酸化蛋白质组学研究3个方面对磷酸化蛋白质组学技术的研究内容和分析策略进行了概述.在此基础上,按照离体实验、活体实验以及毒性作用通路分析3部分对磷酸化蛋白质组学在环境毒理研究中的应用进行了详细阐述.最后,总结了目前磷酸化蛋白质组学研究的不足,并有针对性地提出了磷酸化蛋白质组学在环境毒理研究中的发展方向.     

Endogenous nitric oxide mediates alleviation of cadmium toxicity induced by calcium in rice seedlings

The effect of calcium chloride (CaCl₂) on rice seedling growth under cadmium chloride (CdCl₂) stress, as well as the possible role of endogenous nitric oxide (NO) in this process, was studied. The growth of rice seedlings was seriously inhibited by CdCl₂, and the inhibition was significantly mitigated by CaCl₂. However, hemoglobin (Hb) and 2-(4-carboxyphenyl)-4, 4,5,5-tetramethylimidazolinel- oxyl-3-oxide (cPTIO) weakened the promotion effect of CaCl₂. The results of NO fluorescence localization suggest that growth accelerated by CaCl₂ might be associated with elevated NO levels. The content of Cd, protein thiols (PBT), and nonprotein thiols (NPT) in cell walls, cell organelles, and soluble fractions, respectively, of rice seedlings decreased considerably in the presence of CaCl₂, whereas the content of pectin, hemicellulose 1 (HC1), and hemicellulose 2 (HC2) increased significantly. Elimination of endogenous NO in Cd+Ca treatment could promote the transportation of Cd²⁺ to cell organelles and soluble fractions and increase the content of NPT and PBT in leaves. In addition, transportation of Cd²⁺ to cell organelles and soluble fractions was retarded in roots, the content of NPT increased, and the content of PBT decreased. With elimination of endogenous NO in Cd+Ca treatment, the content of pectin, HC1, and HC2 decreased significantly. Thus, Ca may alleviate Cd toxicity via endogenous NO with variation in the levels of NPT, PBT, and matrix polysaccharides.     

Droplet size spectra and deposits of two aerially sprayed Bacillus thuringiensis formulations on artificial samplers and live foliage

Abstract

Two commercial formulations of Bacillus thuringiensis var. kurstaki (BTK), Foray^® 48B and Thuricide^® 48LV, were applied aerially over nine spray blocks in a hardwood forest in West Virginia in 1991. Droplet spectra and spray mass deposits were determined using water‐sensitive paper strips (WSPS), glass micro‐fiber filters (GMFFs), glass plates and castor oil. Mass deposits of BTK were also assessed on natural foliage by two bioassay methods, i.e., feeding of homogenized foliage containing a starch‐sucrose solution and force‐feeding bioassay of foliar extracts containing re‐dissolved protein precipitate. Deposits on canopy foliage and ground samplers were also assessed by total protein assay and enzyme‐linked immunosorbent assay (ELISA). Droplet spectra on the WSPS were different from those on castor oil. Droplets on horizontal ground WSPS were larger than those on vertical ground WSPS. WSPS placed at canopy level collected more droplets than those at ground level. The total protein deposits (ng/cm²) were consistently higher on all blocks than the delta‐endotoxin protein deposits. Spray mass recovery on the ground samplers were low, and ranged from 2.9 to 8.0% of the applied rates.     

Distribution and Use of Income from Bushmeat in a Rural Village,Central Gabon

Abstract: Bushmeat hunting is an activity integral to rural forest communities that provides a high proportion of household incomes and protein requirements. An improved understanding of the relationship between bushmeat hunting and household wealth is vital to assess the potential effects of future policy interventions to regulate an increasingly unsustainable bushmeat trade. We investigated the relationship between hunting offtake and household wealth, gender differences in spending patterns, and the use of hunting incomes in two rural forest communities, Central Gabon, from 2003 to 2005. Households in which members hunted (hunting households) were significantly wealthier than households in which no one hunted (nonhunting households), but within hunting households offtakes were not correlated with household wealth. This suggests there are access barriers to becoming a hunter and that hunting offtakes may not be the main driver of wealth accumulation. Over half of the money spent by men in the village shop was on alcohol and cigarettes, and the amount and proportion of income spent on these items increased substantially with increases in individual hunting offtake. By contrast, the majority of purchases made by women were of food, but their food purchases decreased actually and proportionally with increased household hunting offtake. This suggests that the availability of bushmeat as a food source decreases spending on food, whereas hunting income may be spent in part on items that do not contribute significantly to household food security. Conservation interventions that aim to reduce the commercial bushmeat trade need to account for likely shifts in individual spending that may ensue and the secondary effects on household economies.