瓦松和长药景天NAD－苹果酸酶的比较研究

通过对专性ＣＡＭ植物瓦松（Ｏｒｏｓｔａｃｈｙｓｆｉｍｂｒｉａｔｕｓ）和兼性ＣＡＭ植物长药景天（Ｓｅ－ｄｕｍｓｐｅｃｔａｂｉｌｅ）的ＮＡＤ－苹果酸酶进行比较研究，在反应系统含５ｍｍｏｌ／ＬＭｎＣｌ＿２，５０μｍｏｌ／ＬＣｏＡ，５ｍｍｏｌ／Ｌ　ＤＴＴ，ｐＨ值为７ｈ，其苹果酸饱和曲线均为双曲线，且瓦松的ＮＡＤ－苹果酸酶对苹果酸极为敏感。光对该酶活性无明显影响。该酶对温度较敏感，其最适温度为５５℃。晴天的酶活明显比阴天高；即使在阴天，瓦松的酶活也较高。在同一温度条件下，瓦松的酶活高于长药景天。     

CPV McAbs对感染FK_(81)细胞的CPV的中和作用

本实验在ＦＫ８１细胞上研究了ＣＰＶＭｃＡｂｓ对ＣＰＶ的中和作用。酶标ＳＰＡ染色证实,在感染细胞的胞浆和胞核中均可见阳性反应物质,表明ＣＰＶＭｃＡｂｓ可穿过细胞膜,中和细胞内的ＣＰＶ。ＨＡ效价测定结果表明,加入ＣＰＶＭｃＡｂｓ的试验组,其ＨＡ效价全部＜１：１０,而未加ＣＰＶＭｃＡｂｓ的对照组,其ＨＡ效价随培养时间延长成倍增长。进一步证实了进入细胞内的ＣＰＶＭｃＡｂｓ可以完全中和细胞内的ＣＰＶ,初步解释了ＣＰＶＭｃＡｂｓ对自然发病的治疗机理     

瓦松的CAM活性与NAD－苹果酸酶的关系

对专一性ＣＡＭ植物瓦松（Ｏｒｏｓｔａｃｈｙｓｆｉｍｂｒｉａｔｕｓ）的ＣＡＭ活性与ＮＡＤ－ＭＥ的关系进行了初步研究，结果表明，瓦松的ＭＡＤ－ＭＥ有明显的昼夜（短期）调节特性，其活性昼高夜低；同时，该活性还存在季节性变化，在７月酶活性可达最高峰，其酶的最适ｐＨ为７，最适温度为５５℃．     

1，4－二取代酰氨基硫脲类化合物（DATCDs）的植物生理效应和应用研究Ⅷ．DATCD－A对黄瓜根系生长代谢的影响

用１ｍｇ／ＬＤＡＴＣＤ－Ａ溶液喷施黄瓜幼苗叶片，吸收后直接影响着根系生长的代谢。与对照比较，ＤＡＴＣＤ－Ａ处理促进根的生长速度，提高脱氢酶活性，相对降低过氧化物酶活性，但同工酶谱带增多。随着ＤＡＴＣＤ－Ａ处理时间延长，蛋白质含量下降，而蛋白水解酶比活性和核酸总量增高。说明ＤＡＴＣＤ－Ａ的调控主要通过影响核酸和蛋白质代谢及酶的活化而起作用，促进根的生长发育，提高根系对养分的吸收与运转能力，保证黄瓜整株的正常生长。     

CAD／CAM在冶金生产中的应用

由四级计算机组成的计算机集成制造系统（ＣＩＭＳ）实现了ＣＡＤ、ＣＡＭ和ＣＡＰ。系统也有与之相适应的ＣＡＰＭ。借助于计算机系统和工艺、设备的综合能力，也是在ＣＡＤ／ＣＡＭ的基础上，实现了ＦＭＳ，这使得在大生产过程中能充分满足每个用户的订货要求。系统的ＭＲＰⅡ对前工序的原料供应以ｊｕｓｔｉｎｔｉｍｅ的原则进行了规划。本系统还在向更高层次的ＣＩＭＳ发展。     

板形最优综合控制算法

对ＣＬＥＣＩＭ带钢冷连轧机板形自动控制（ＡｕｔｏｍａｔｉｃＦｌａｔｎｅｓｓＣｏｎｔｒｏｌ，简称ＡＦＣ）系统进行了深入的研究．给出板形目标曲线、评价板形的性能指标函数及综合ＡＦＣ系统的结构，推导出最优综合控制算法．该算法的优越性在于：充分利用输入信息，全面考虑多个执行机构对轧件各个区域的作用，避免了各控制之间的相互影响，并易于在线实现．该ＡＦＣ系统已在某四机架冷连轧机上实验运行，实验结果表明：投入该ＡＦＣ系统，板形精度比手动控制平均提高７５％     

一个家蚕基因组MAR的克隆及其初步分析

家蚕（Ｂｏｍｂｙｘｍｏｒｉ）基因组大片段ＤＮＡ经ＢａｍＨＩ完全酶解后,克隆到质粒ｐＵＣ１８中而构建成一个家蚕基因组文库．通过与家蚕细胞核基质的体外结合,从该文库中筛选到一个包含ＭＡＲ的克隆ｐＣ１１ｅ,其中外源插入片段Ｃ１１ｅ长约２．３ｋｂ．Ｃ１１ｅ的限制性酶谱分析及其酶切片段的体外结合实验表明,ＭＡＲ位于Ｃ１１ｅ上的ＳｐｈＩ和ＨｉｎｃⅡ位点之间,长１．０ｋｂ．由于这是家蚕中发现的第一个ＭＡＲ,因此我们称之为ＢｍＭＡＲ１．进一步借助ＤＮａｓｅＩ敏感性分析和ＳｏｕｔｈｅｒｎＢｌｏｔ,对ＢｍＭＡＲ１在家蚕细胞内与核基质结合的情况以及它与人β干扰素（ｈｕＩＦＮ－β）基因５′上游ＭＡＲ之间的同源性进行了研究．     

基于多模型的自适应控制研究进展

基于多模型的自适应控制（ＭｕｌｔｉｐｌｅＭｏｄｅｌＢａｓｅｄＡｄａｐｔｉｖｅＣｏｎｔｒｏｌ,ＭＭＡＣ）其目的在于对各种复杂的、具有高度不确定性的、快时变的系统给出一种行之有效的控制方法．文中对这一领域的研究进展进行了回顾、分析与总结．介绍了ＭＭＡＣ的基本原理和基本思想,给出了ＭＭＡＣ的结构框图,分析讨论了其中存在的几个重要问题,并指出了与这些问题相关的未来的研究方向     

基于冲模CAD／CAM开发平台的构件库系统的研制

基于冲模ＣＡＤ／ＣＡＭ系统开发平台的设计思想，提出并论述了基于冲模ＣＡＤ／ＣＡＭ系统开发平台软构件库中之软构件的定义、分类、描述与管理机制以及软构件库的树形结构图与软构件库系统——ＳＣＢＭＳ（ＳｏｆｔｗａｒｅＣｏｍｐｏｎｅｎｔＢａｓｅＭａｎａｇｅｍｅｎｔＳｙｓｔｅｍ）的功能模型及其实现思路，开发了一个原型ＳＣＢＭＳ．     

1,4—二取代酰氨基硫脲类化合物（DATCDs）的植物生理效应…

用１ｍｇ．ＬＤＡＴＣＤ－Ａ溶液喷施黄瓜幼苗叶片，吸收后直接影响着根系生长的代谢，与对照比较，ＤＡＴＣＤ－Ａ处理保进根的生长速度，提高脱氢酶活性，相对降低过氧化物酶活性，但同工酶谱带增多。随着ＤＡＴＣＤ－Ａ处理时间延长，蛋白质含量下降，而蛋白水解酶比活性和核酸总量增高。     

肌苷产生菌枯草芽孢杆菌分批发酵的代谢流分析

为了更好地掌握代谢规律和代谢方式，代谢流作为一个关键而重要的变量需要测定．然而，由于代谢流测定的困难，在许多代谢研究中代谢流并没有被完全应用．在肌苷高产菌枯草芽孢杆菌中，利用得到的实验数据包括葡萄糖的消耗速率和代谢主产物以及副产物的形成速率，利用代谢通量平衡模型，得到糖酵解、三羟酸循环及磷酸戊糖途径的代谢流，并对其进行了分析．     

Analysis of regulatory architectures in BST

Based on the data envelopment analysis (DEA) theory, the optimal pathway of metabolic reaction networks in biochemical systems is studied. After calculating the mixed-integer linear programming (MILP) model given by Bailey et al. twice, the decision making units (DMU) and the prediction model of DEA are constructed, where the inputs are levels of manipulated parameters (enzyme) and outputs are concentrations of metabolites. When the metabolic networks are reconstructed, the data are obtained by calculating MILP framework twice and the optimal levels of the manipulated parameter at different regular loops are predicted, thus simplifying the calculations of Bailey's.     

酵母耐高温分子机制的研究进展

耐高温是酵母在工业生产中的重要特性之一.近年来,人们对耐高温酵母的应用研究日益重视并取得较大的进展,但其耐高温分子机制尚未明确.目前的研究结果表明,酵母耐高温机制涉及代谢网络调控、信号转导途径及多基因/蛋白共同作用等方面.本文从代谢途径、基因表达、酶活特性和蛋白质相互作用等4个方面综述当前酵母耐高温分子机制的研究进展,...     

化学防癌药物keap1-nrf2信号通路活化剂的研究进展

化学防癌是应用天然的或合成的化学物质来阻断、抑制或治疗癌症的过程,这一过程与肝内的Ⅱ相代谢酶的作用有关.研究表明,Keap1/Nrf2/ARE信号传导通路能有效地诱导Ⅱ相代谢酶基因的表达,而这一作用是作为碱性亮氨酸拉链蛋白家族的转录因子nrf2从胞质蛋白keap1上解离,然后转位至核内并与ARE结合后完成.这一传导通路机制加深了我们对于化学防癌机制的认识,并且为化学防癌药物的筛选提供了有效的靶点.就以Keap1/Nrf2/ARE传导通路为靶点的化学防癌药物的国内外研究进展进行了综述.     

Domain-specific recruitment of amide amino acids for protein synthesis

The formation of aminoacyl-transfer RNA is a crucial step in ensuring the accuracy of protein synthesis. Despite the central importance of this process in all living organisms, it remains unknown how archaea and some bacteria synthesize Asn-tRNA and Gln-tRNA. These amide aminoacyl-tRNAs can be formed by the direct acylation of tRNA, catalysed by asparaginyl-tRNA synthetase and glutaminyl-tRNA synthetase, respectively. A separate, indirect pathway involves the formation of mis-acylated Asp-tRNA(Asn) or Glu-tRNA(Gln), and the subsequent amidation of these amino acids while they are bound to tRNA, which is catalysed by amidotransferases. Here we show that all archaea possess an archaea-specific heterodimeric amidotransferase (encoded by gatD and gatE) for Gln-tRNA formation. However, Asn-tRNA synthesis in archaea is divergent: some archaea use asparaginyl-tRNA synthetase, whereas others use a heterotrimeric amidotransferase (encoded by the gatA, gatB and gatC genes). Because bacteria primarily use transamidation, and the eukaryal cytoplasm uses glutaminyl-tRNA synthetase, it appears that the three domains use different mechanisms for Gln-tRNA synthesis; as such, this is the only known step in protein synthesis where all three domains have diverged. Closer inspection of the two amidotransferases reveals that each of them recruited a metabolic enzyme to aid its function; this provides direct evidence for a relationship between amino-acid metabolism and protein biosynthesis.     

Novel renin inhibitors containing the amino acid statine

The proteolytic enzyme renin (EC3.4.99.19) cleaves the protein substrate angiotensinogen to yield angiotensin I, the decapeptide substrate transformed by converting enzyme into the pressor substance angiotensin II. Although the contribution of this pathway to the maintenance of normal blood pressure is unclear, it seems to be a major factor in various hypertensive states. Important progress in the control of hypertension has been achieved by development of the potent inhibitors SQ-14,225 (captopril) and MK-421 (enalapril maleate), which block the generation of angiotensin II by the inhibition of angiotensin converting enzyme. An attractive alternative to the inhibition of converting enzyme would be the blockade of the preceding step in the cascade, the renin reaction. We report here new highly potent (IC50 = 10(-9)-10(-8) M) competitive inhibitors of renin in which statine, (3S,4S)-4-amino-3-hydroxy-6-methylheptanoic acid, is incorporated into analogues of the pig renin substrate (Fig. 1).     

S-adenosylmethionine--a novel regulator of aspartate kinase

Man derives 70% of his dietary requirements of protein directly from the grains of cereals and legumes. These sources are respectively deficient in lysine (and secondarily threonine) and methionine and much effort is being devoted to their improvement. All three amino acids are derived from aspartate via a common metabolic pathway (Fig. 1) in which the first reaction catalysed by aspartate kinase is a key regulatory step limiting their production. In microorganisms, regulation of aspartate kinase occurs by a variety of mechanisms, commonly involving feedback inhibition of one or more isoenzymes by Lys plus Thr, Lys alone or Thr alone. On the other hand, Met control of this step does not seem to conform to a general pattern. Met represses, but does not inhibit aspartate kinase II of Escherichia coli; in other species Met can enhance or modify the effects of Lys or Thr. Similarly, varied controls involving Lys and Thr have been reported for the enzymes from higher plants with only one report of an effect of Met. In contrast to these previous results, we suggest here that the methionine derivative (S)-S-adenosyl-L-methionine (AdoMet) is an important regulator of the Lys-sensitive aspartate kinase of higher plants, and that this regulatory mechanism is highly conserved. There is thus a major synergistic interaction of the two nutritionally deficient amino acids Lys and Met to inhibit their own syntheses at the primary regulatory step in the pathway.     

植物对重金属耐性机理的研究进展

从两方面综述了植物对重金属胁迫的耐性机理.（1）植物生理生化代谢途径对重金属胁迫的适应性反应,包括与重金属解毒螯合相关的硫代谢途径;与植物抗氧化相关的活性氧代谢途径;与酚类物质生成及植物木质化形成相关的次生代谢途径.（2）植物对重金属耐性的分子机理研究,包括对与重金属胁迫相关代谢途径中关键酶基因克隆和功能鉴定;金属硫蛋白（MT）和膜金属转运蛋白基因表达和调控;与重金属胁迫相关的植物逆境信号传导的研究.随着基因组学的发展,通过进化各异的模式生物基因组比较及通过使用一些如基因差异表达技术、表达序列高通量分析技术和功能获得或突变体互补等技术在植物重金属耐性机理的研究中也取得了一些进展.     

减少活性污泥法中剩余污泥产率的研究

比较了4种解偶联剂(对氯酚、间氯酚、间硝基酚和邻硝基酚)在活性污泥法中减少污泥产率的效果.4种解偶联剂的研究表明,间氯酚在减少污泥产率的方面是最有效的,同时对污水处理的效果影响较小,当间氯酚的浓度为20mg/L时,与空白实验相比较,污泥产率下降了86.9%,COD的去除率下降了13.2%;解偶联剂的酸性常数pKa很大程度上影响了其在减少污泥产率方面的效果,即pKa值越低的解偶联剂对减少污泥产率的效果越好.选择解偶联剂和其最佳投药量取决于同时满足污泥减量与COD去除率要求的一个平衡点.