抑制二种酶的二酶系统底物抑制的非稳态动力学

以非稳态酶动力学的布尔函数图形方法,来研究一类抑制二种酶的二酶系统底物抑制的“稳态前”非稳态动力学,推导出此类反应的“稳态前”非稳态酶动力学方程,并对引动力学方程进行了研究,讨论了这类二酶系统底物抑制动力学的“稳态前”非稳态动力学过程。     

Order Bi Bi机制的多底物酶的非稳态酶动力学研究

本文对Ｏｒｄｅｒ Ｂｉ Ｂｉ机制的多底物酶的非稳态酶动力学机制进行了研究，推导出了此种多底物酶的非稳态动力学方程，并对此动力学方程进行了讨论，分析了多底物酶的非稳态酶动力学过程。     

双曲线型竞争抑制酶体系的非稳态酶动力学

本文以非稳态酶动力学的布尔函数图形方法[1]，来研究双曲线型竞争抑制酶体系的非稳态酶动力学，推导出此类反应的非稳态酶动力学方程，并对此动力学方程进行了讨论，分析了双曲线型竞争抑制体系的非稳态酶动力学过程。     

有两个酶结合位点的线性混合抑制非稳态动力学研究

以非稳态酶动力学的布尔函数图形方法,来研究一类有两个酶结合位点的线性混合抑制非稳态动力学问题,导出此类反应的非稳态酶动力学方程,并对此动力学方程进行了讨论,分析了此类非竞争性抑制的非稳态酶动力学的动力学过程。结果,当反应时间较大时,反应速度是以指数衰减或小阻尼振动的方式趋向稳态。     

二酶系统竞争性抑制稳态动力学的布尔函数图论研究

本文以稳态酶动力学的布尔函数图形方法，来研究一类二醇系统的竞争性抑制稳态动力学，推导出此类反应的稳态酶动力学方程，并对此动力学方程进行了讨论，分析了这类二酶系统的竞争性抑制稳态动力学过程。     

二酶系统非竞争性抑制的稳态酶动力学布尔函数图论研究

用稳态酶动力学的布尔函数图形方法^[1],对来在二酶系统非竞争性抑制的稳态酶动力学进行了研究,推导出此类反应的稳态酶动力学方程,并对该方程进行了讨论,分析了这类二酶系统的非竞争性抑制稳态动力学过程。     

非竞争性抑制作用的非稳态酶动力学分析

本文对非竞争性抑制作用的非稳态酶动力学机制进行了研究，推导出了晨竞争性抑制作用的非稳态酶动力学方程，并对此动力学方程进行了讨论，分析了非竞争性抑制作用的非稳态酶动力学过程。     

山梨酸工业废水生物处理动力学研究

分析了微生物降解山梨酸工业废水的机理。在Monod方程的基础上推导出稳态条件下废水降解动力学模式。利用最小二乘法对动力学参数进行了优化设计。     

琥珀酸半醛还原酶AKR7A5的稳态动力学机理分析

琥珀酸半醛还原酶的抑制剂可作为缓解琥珀酸半醛脱氢酶缺陷病症状的潜在药物.酶抑制剂的研发要以酶的动力学性质为基础,但琥珀酸半醛还原酶的稳态动力学性质还不清楚.本文通过对琥珀酸半醛还原酶AKR7A5稳态动力学性质的分析,判断AKR7A5是按照有序的三元复合物反应机理催化反应;在此基础上,推导出琥珀酸半醛发生底物抑制是由于错误地与AKR7A5:NADP+二元复合物结合;底物的结构类似物琥珀酸体现出反竞争抑制剂的特点,只能与AKR7A5:NADP+二元复合物相互作用,暗示只有通过抑制剂、酶、NADP+复合物的方向入手,才能获得反竞争抑制剂与AKR7A5的复合物晶体结构.     

复合型生物絮凝剂产生菌发酵动力学研究(英文)

为了优化复合型生物絮凝剂生产的发酵过程,对絮凝剂产生菌F2-F6发酵生产复合型生物絮凝剂的动力学进行了研究,利用数学建模方法得到了描述F2-F6菌体生长,絮凝剂合成及底物消耗动力学方程和动力学参数.实验和方程数据的比较结果证明动力学方程计算值与实验值拟合良好,为复合型生物絮凝剂的放大工业化生产提供依据.     

A model for interfacial activation in lipases from the structure of a fungal lipase-inhibitor complex

Lipases are hydrolytic enzymes which break down triacylglycerides into free fatty acids and glycerols. They have been classified as serine hydrolases owing to their inhibition by diethyl p-nitrophenyl phosphate. Lipase activity is greatly increased at the lipid-water interface, a phenomenon known as interfacial activation. X-ray analysis has revealed the atomic structures of two triacylglycerol lipases, unrelated in sequence: the human pancreatic lipase (hPL)4, and an enzyme isolated from the fungus Rhizomucor (formerly Mucor) miehei (RmL). In both enzymes the active centres contain structurally analogous Asp-His-Ser triads (characteristic of serine proteinases), which are buried completely beneath a short helical segment, or 'lid'. Here we present the crystal structure (at 3 A resolution) of a complex of R. miehei lipase with n-hexylphosphonate ethyl ester in which the enzyme's active site is exposed by the movement of the helical lid. This movement also increases the nonpolarity of the surface surrounding the catalytic site. We propose that the structure of the enzyme in this complex is equivalent to the activated state generated by the oil-water interface.     

Intrinsic dynamics of an enzyme underlies catalysis

A unique feature of chemical catalysis mediated by enzymes is that the catalytically reactive atoms are embedded within a folded protein. Although current understanding of enzyme function has been focused on the chemical reactions and static three-dimensional structures, the dynamic nature of proteins has been proposed to have a function in catalysis. The concept of conformational substates has been described; however, the challenge is to unravel the intimate linkage between protein flexibility and enzymatic function. Here we show that the intrinsic plasticity of the protein is a key characteristic of catalysis. The dynamics of the prolyl cis-trans isomerase cyclophilin A (CypA) in its substrate-free state and during catalysis were characterized with NMR relaxation experiments. The characteristic enzyme motions detected during catalysis are already present in the free enzyme with frequencies corresponding to the catalytic turnover rates. This correlation suggests that the protein motions necessary for catalysis are an intrinsic property of the enzyme and may even limit the overall turnover rate. Motion is localized not only to the active site but also to a wider dynamic network. Whereas coupled networks in proteins have been proposed previously, we experimentally measured the collective nature of motions with the use of mutant forms of CypA. We propose that the pre-existence of collective dynamics in enzymes before catalysis is a common feature of biocatalysts and that proteins have evolved under synergistic pressure between structure and dynamics.     

Multiple conformations of a protein demonstrated by magnetization transfer NMR spectroscopy

It is generally accepted that a globular protein in its native state adopts a single, well-defined conformation. However, there have been several reports that some proteins may exist in more than one distinct folded form in equilibrium. In the case of staphylococcal nuclease, evidence for multiple conformations has come from electrophoretic and NMR studies, although there has been some controversy as to whether these are actually interconvertible forms of the same molecular species. Recently, magnetization transfer (MT)-NMR has been developed as a means of studying the kinetics of conformational transitions in proteins. In the study reported here, this approach has been extended and used to demonstrate the presence of at least two native forms of nuclease in equilibrium and to study their interconversion with the unfolded state under the conditions of the thermal unfolding transition. The experiments reveal that two distinct native forms of the protein fold and unfold independently and that these can interconvert directly as well as via the unfolded state. The spectra of the different forms suggest that they are structurally similar but the MT experiments show that the kinetics of folding and unfolding are quite different. Characterization of this behaviour will, therefore, have important implications for our understanding of the relationship between structure and folding kinetics.     

酶的分形反应动力学

应用分形理论推导了酶催化的基元反应动力学方程，针对方程的物理意义做了简单的讨论。     

玉米淀粉酶催化糖化的反应动力学模型

发现玉米淀粉的酶糖化反应，可以用酶的三态模型描述，而且该反应具有单底物酶动力学犍征。用三态模型导出的反应动力学模型式计算反应速度等参数，其计算结果实验数据基本一致。