新疆艾丁湖中度嗜盐苯酚降解菌多样性研究

高盐含酚废水属于极难处理的废水之一,筛选具有生物学降解能力的嗜盐菌有助于解决这一难题。从新疆艾丁湖盐湖中分离筛选能够降解苯酚的中度嗜盐菌,了解盐湖中度嗜盐苯酚降解菌的多样性组成和降解能力。研究结果表明,10%(质量分数)的盐浓度条件下,分离得到166株嗜盐菌,通过以苯酚为唯一碳源的培养基进行降解活性筛选后得到45株阳性菌,根据细菌16S rRNA基因序列系统进化分析,这45株菌分别归类到3个门,5个科,9个属。其中拟诺卡氏菌属(Nocardiopsis)是优势菌,占总量的68.8%,其余菌分布于Bacillus、Gracilibacillus、Pontibacillus、Halobacillus、Marinococcus和Halomonas属。在含100 mg/L苯酚的液体培养基,经过10 d培养后,这45株菌降解效率为1%~17%。本研究为工业应用提供了嗜盐微生物种质资源,极具进一步发掘和研究价值。     

栓皮栎叶片δ13C和δ15N的纬向趋势及其影响因子

以东亚广布种栓皮栎为例,通过对南北样带(26°-40° N)上7个群体的调查取样,并结合2个生活史阶段,探讨栓皮栎碳氮同位素比值随纬度环境的变异规律.结果表明: 在纬向梯度上,栓皮栎叶片δ¹³C和δ¹⁵N随纬度的增加分别呈现非线性的增加和下降趋势,且成年树叶片δ¹³C和δ¹⁵N均显著高于幼树;同时,树龄和纬度对叶片δ¹⁵N和δ¹³C均无显著交互作用,表明栓皮栎幼树和成年树纬向环境变化的响应较为一致.随机森林模型结果显示,栓皮栎叶片δ¹⁵N主要受土壤养分,如土壤有机质、磷和氮含量的影响,而叶片δ¹³C主要受水分因子,如空气相对湿度、降水量等的影响.     

棉花GhVHA A基因的原核表达及其重组大肠杆菌的抗逆性分析

为进一步验证棉花GhVHA-A基因的功能,该研究将棉花GhVHA-A基因构建到原核表达载体pET28a上,利用IPTG诱导其在大肠杆菌BL21(DE3)中高效表达,同时对重组大肠杆菌BL21(pET28a-GhVHA-A)进行抗逆性分析。结果表明:(1)半定量RT-PCR分析发现,棉花幼苗液泡膜H+-ATPase基因(GhVHA-A)表达水平受脱水和高盐胁迫诱导。(2)将1 872bp长的编码区序列连接至原核表达载体pET28a上,成功构建了原核表达载体pET28a-GhVHA-A;SDS-PAGE电泳检测结果表明,在70kD左右处有1条特异表达的蛋白质条带,与预期的目的产物大小一致。(3)重组菌BL21(pET28a-GhVHA-A)的抗逆性分析发现,重组菌对PEG6000(20%)和NaCl(0.5mol/L)的抗性明显高于对照菌株BL21(pET28a),表明GhVHA-A基因在大肠杆菌中表达后能够增强菌株的抗性。本研究结果为GhVHA-A基因在植物抗逆基因工程中的应用提供了理论依据。     

专访韩国现代风景园林开拓者吴辉英教授

韩国风景园林取得突出成就主要源自一个人的引领和启发：被韩国人民称为“韩国弗雷德里克·劳·奥姆斯特德”的吴辉英教授。从对吴辉英教授的采访中我们可知,作为一个国家公职人员,在韩国快速工业化和城市化进程中,他领导制定了发展和保护政策。在为朴正熙总统工作期间,吴教授撰写了很多国家环境、规划和发展的法规与政策,并一直将风景园林师纳入其中作为重要角色。他促成了1977年自然环境保护法（NECA）的制定。他还着手建立将风景园林作为一个独立于建筑、林业和园艺的专业产业的立法基础。吴教授促成了韩国风景园林研究院的基础建设,同时促进了专业和商业执照的确立。作为韩国第一个向国家介绍风景园林的人,吴博士一直是学术界和出版界的领军人物。吴教授还建议风景园林界要善于分享愿景,并提供新的视野,让我们一起找到更好的方法来改善、再生和修复城市和环境     

Dramatically stabilized phosphotriesterase-polymers for nerve agent degradation

Phosphotriesterase (EC 3.1.8.1) was immobilized within a polyurethane foam matrix during polymer synthesis using a prepolymer synthesis strategy. In addition to retaining greater than 50% of the enzyme specific activity, numerous benefits were incurred upon immobilization. Orders of magnitude increases in storage and thermal stability (net stabilization energy = 12.5 kJ/mol) were observed without the need for enzyme premodification. The immobilized enzyme system was protease resistant and seemed to display no adverse effects from immobilization, such as an alteration of enzyme function. The organic solvent, dimethyl sulfoxide, also exhibited a stabilizing effect on phosphotriesterase enzyme systems over a range of intermediate concentrations. We attribute these effects in part to direct interaction between the aprotic solvent and metal containing residues present at the enzyme's active site. Our data demonstrate that just 2.5 kg of immobilized enzyme may be sufficient to degrade 30,000 tons of nerve agent in just 1 year. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 54: 105-114, 1997.     

外源性TH基因在帕金森氏病鼠脑内的表达——行为和TH免疫组化的研究

用成年大鼠７５只,给右侧黑质区注射６－羟基多巴胺（６－ＯＨＤＡ）,损毁黑质多巴胺能神经元,制备偏侧帕金森氏病（ＰＤ）鼠模型。四周后,注射阿朴吗啡（ＡＰＯ）诱发大鼠向左侧旋转。旋转数为每分钟７次以上的３５只ＰＤ鼠作实验用。其中实验组１５只,对照组２０只。向实验组ＰＤ鼠右侧纹状体多点植入含大鼠酪氨酸羟化酶ｃＤＮＡ（ＴＨｃＤＮＡ）的真核表达载体ｐＳＶＫ３－ＴＨ和脂质体Ｌｉｐｏｆｅｃｔｉｎ混合的基因转染复     

Preliminary investigation of sequence-independent DNA binding proteins in rat skeletal muscle sarcoplasmic reticulum and their function

To observe the binding of plasmid DNA to non-nuclear DNA binding proteins in sarcoplasmic reticulum (SR) and the effects of this binding on SR function, sarcoplasmic reticulum proteins in rat skeletal muscle were isolated by differential centrifuge and sucrose density-gradient centrifuge. The results showed that there are two sequence-independent DNA binding proteins in SR proteins, the molecular weights of which are 83 and 58 ku, respectively. Ca²⁺ uptake and release of SR were remarkably promoted by the binding of plasmid DNA to DNA binding proteins in SR, the mechanism is probably through increasing of Ca²⁺-ATPase activity in SR and changing of character of Ca²⁺ release channel ryanodine receptors induced by the binding. These results suggest that there exist DNA binding proteins in SR and its binding to DNA may affect Ca²⁺ transport of SR.