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CO_(2)化学酶转化的突破:实现立体化学完全可控的可持续人工合成己糖

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Science Bulletin 2023年第20期68卷 2291-2292页

作者： manfred t.reetz tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China Biocatalysis Section Max-Planck-Institut fur KohlenforschungMulheim an der Ruhr 45470Germany

the capture and transformation of the greenhouse gas CO_(2) into high-value products is currently of paramount importance worldwide,with many different approaches being conceived and tested[1-6].the transformation CO_(2) into carbohydrates is a particularly intriguing idea,but putting it into reality is challenging due to the necessary complete control in the creation of stereo-centers and ensuring sufficient *** far,the results are not overly convincing[7].the inspiration for solving this fundamental problem is manifold,inter alia,because carbohydrates(sugars)contribute significantly to energy storage and provide carriers for human living,especially important biologically active *** also constitute the main resource for industrial biomanufacturing.

关键词：立体化学 manifold sugar

细胞色素P450 Kemp消除酶的改造及新型催化机制解析

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Chinese Journal of Catalysis 2023年第4期47卷 191-199页

作者：李爱涛汪倩宋希彤张小栋黄建文陈纯琪郭瑞庭王斌举 manfred t.reetz 湖北大学生命科学学院工业生物技术湖北省重点实验室省部共建生物催化与酶工程国家重点实验室湖北武汉430062 厦门大学化学化工学院理论与计算化学福建省重点实验室固体表面物理化学国家重点实验室福建厦门360015 马克斯.普朗克煤炭研究所德国慕尼黑中国科学院天津工业生物技术研究所天津300308

传统的Kemp消除反应可以通过氢氧化钾和三烷基胺等碱性物质,催化底物苯并异恶唑开环生成产物2-氰基苯酚.三十年来,Kemp消除反应一直被用作模式反应来设计或定向进化新型生物酶催化剂,从而揭示未知的酶催化机制的复杂性,增强对酶催化机... 详细信息

传统的Kemp消除反应可以通过氢氧化钾和三烷基胺等碱性物质,催化底物苯并异恶唑开环生成产物2-氰基苯酚.三十年来,Kemp消除反应一直被用作模式反应来设计或定向进化新型生物酶催化剂,从而揭示未知的酶催化机制的复杂性,增强对酶催化机制的理解.目前科研人员使用不同的蛋白作为骨架设计能够高效催化Kemp消除反应的人工酶.例如Hilvert及Mayo等基于人工酶HG3.17,设计获得了Kemp消除酶,可以催化5-硝基苯并异恶唑生成产物2-氰基-4-硝基苯酚.通过17轮定向进化获得的最终突变体展现出与天然酶相近的催化活性(k_(cat)/Km=230000 L mol^(-1)s^(-1);k_(cat)=700 s^(-1)).该研究不仅表明蛋白质工程可以进化出高效的生物酶,量子力学/分子力学(QM/MM)分析还揭示了突变体催化活性提高的分子机制.与酸碱催化的Kemp消除反应不同,最近Korendovych等报道以肌红蛋白作为骨架基于氧化还原机制的Kemp消除反应,通过开发一种独特的基于核磁共振(NMR)的蛋白质定向进化技术,快速鉴定出热点氨基酸位点并获得了高催化活性的人工酶突变体,其同样达到了天然酶的催化活性.此前我们研究(***.,2017,8,14876)发现,与传统的酸碱催化机制完全不同,细胞色素P450-BM3能够通过氧化还原的机制催化Kemp消除反应.本文继续以P450-BM3为蛋白骨架,对其进一步改进以提高催化活性.以P450-BM3突变体F87G(kcat=3.0s^(-1))为模板,借助双密码子(酪氨酸和赖氨酸,Y-K)饱和突变策略,对其活性中心的六个关键氨基酸位点进行组合突变,经过筛选获得了活性大幅度提高的三突变体F87G/L75Y/t438K(k_(cat)=27.4s^(-1)).为进一步解析其催化活性提高的分子机制,首先对该突变体与底物复合物的晶体结构进行了解析,结果发现底物在突变体活性口袋的构象与野生型P450-BM3完全不同,底物的硝基指向了Heme辅基.对其进行了QM/MM计算研究,发现Heme-Fe(II)首先将电子转移到底物并与硝基配位,随后,有效促进了底物N-O键还原裂解,并使生成的中间产物Heme-Fe(III)-NO_(2)和苯氧基阴离子更稳定,最后,通过键的旋转和质子转移生成产物2-氰基-4-硝基苯酚.由此可见,同一P450酶的不同突变体能够以两种不同的底物结合模式以及氧化还原机制来催化Kemp消除反应.综上,本文获得了P450酶催化Kemp消除反应构效关系和催化机制新的认识,为进一步改造该酶提高其催化活性提供借鉴.

关键词： Kemp消除反应氧化还原机理 P450单加氧酶量子力学/分子力学 X射线结构饱和突变

Book review of“Enzyme engineering:Selective catalysts for applications in biotechnology,organic chemistry,and life science”

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Green Synthesis and Catalysis 2023年第2期4卷 77-77页

作者： manfred t.reetz Zhoutong Sun Ge Qu tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China Biocatalysis Section Max-Planck-Institut für KohlenforschungKaiser-Wilhelm-Platz 1Mülheiman der Ruhr 45470Germany

this book[1]begins with an introductory chapter in which the history of directed enzyme evolution is briefly presented and the different gene mutagenesis techniques are outlined,followed by a comprehensive chapter des... 详细信息

关键词： Directed evolution Rational design Enzyme engineering Methodology Biocatalysis

Candida antarctica Lipase B（CALB）的定向进化研究

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Candida antarctica Lipase B（CALB）的定向进化研究

第八届中国酶工程学术研讨会

作者：吴起 manfred t.reetz 浙江大学化学系 Max-Planck-Institut fr Kohlenforschung Muelheim45470Germany

＜正＞Candida antarctica Lipase B（CALB）是目前在学术界、工业界应用最广泛的脂肪酶之一,具有醇立体选择性高、有机相稳定性好、催化效率高、底物谱广等突出优点。在醇和胺的立体选择性拆分反应、转酯化反应、聚合反应、去保护和去...

＜正＞Candida antarctica Lipase B（CALB）是目前在学术界、工业界应用最广泛的脂肪酶之一,具有醇立体选择性高、有机相稳定性好、催化效率高、底物谱广等突出优点。在醇和胺的立体选择性拆分反应、转酯化反应、聚合反应、去保护和去对称化过程等领域都有重要应用。

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良师有效指导促进科学进步

生物学杂志 2020年第6期37卷 1-6页

作者：曼弗雷德·雷茨孙周通(编译) 德国马普煤炭化学研究所米尔海姆45470 中国科学院天津工业生物技术研究所天津300308

对博士生和博士后进行有效指导是每位导师的重要职责,因为它确保了科学的进步。然而,囿于个人性格和文化背景,每位导师都有自己独特的风格。但也存在一些国际惯例,其中就包括道德规范。在这篇受邀文章中,结合生物催化背景,介绍指导方式... 详细信息

对博士生和博士后进行有效指导是每位导师的重要职责,因为它确保了科学的进步。然而,囿于个人性格和文化背景,每位导师都有自己独特的风格。但也存在一些国际惯例,其中就包括道德规范。在这篇受邀文章中,结合生物催化背景,介绍指导方式,仅供参考。有效的指导是导师-学生双向的,同时会介绍两者应遵循的准则,如:导师应允许学生针对课题提出自己的见解,并且不应惧怕导师;优秀导师应鼓励学生积极参加国内外的学术会议,并提交报告或海报,积极建立自己潜在的合作社交网络。总是要求学生们一定要实事求是,无论是发表演讲、海报或在网页上,都不要夸大自己的研究结果。导师应投入必要的时间指导学生撰写科技论文,尤其是选题环节。另外,总是鼓励自己的学生周末要充分休息,这样才能以饱满的状态投入到创新研究中。对于国际博士后,还建议他们利用假期或周末远足,如去德国一些城市及其博物馆、剧院等学习当地的文化知识;同时也鼓励德国的博士后有机会到其他国家,如去中国参观学习当地文化知识,这对他们职业生涯的发展非常有帮助。

关键词：导师制指导方针道德规范职业规划化学生物学生物催化酶工程

Impact of Pollutant Concentration and Particle Deposition on the Radiative Flow of Casson-Micropolar Fluid between Parallel Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 665-690页

作者： Ghaliah Alhamzi Badr Saad t.Alkahtani Ravi Shanker Dubey Vinutha Kalleshachar Neelima Nizampatnam Department of Mathematics and Statistics College of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11564Saudi Arabia Department of Mathematics College of ScienceKing Saud UniversityRiyadh11989Saudi Arabia Department of Mathematics Amity School of Applied SciencesAmity University RajasthanJaipur302002RajasthanIndia Department of Studies in Mathematics Davangere UniversityDavangere577002India Department of Electronics and Communication Engineering Amrita School of EngineeringAmrita Vishwa VidyapeethamBengaluru560035India

Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental *** the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge *** waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution *** study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle *** explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are *** governing equations are transformed into ordinary differential equations with the help of suitable similarity *** Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary *** integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of *** outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current *** reveal that concentration upsurges as the micropolar parameter *** concentration reduces with an upsurge in the thermophoretic *** upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass *** surface drag force declines for improved values of porosity and micropolar parameters.

关键词： Micropolar fluid thermal radiation porous medium thermophoretic particle deposition waste discharge concentration

Ultrastructural cellular signatures: does cellular form follow function?

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National Science Review 2019年第5期6卷 861-863页

作者： manfred Auer Molecular Biophysics and Integrated Bioimaging Division Lawrence Berkeley National Laboratory

In his watershed 1896 essay the tall Office Building Artistically Considered,protomodern architect Louis Sullivan famously declared that ‘form follows function’.Could this concept also hold true in biology? Have cel... 详细信息

关键词： Ultrastructural cellular signatures does cellular form follow function

transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN t.ASGHAR Z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

this paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. the influence of magnetic fields is also inspected in terms of their physical characteristics. to depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).the effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： Peclet number

the impact of alpha-fetoprotein(AFP),child-turcotte-pugh(CtP)score and disease staging on the survival of hepatocellular carcinoma(HCC)patients:a retrospective cohort from single oncology center

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Oncology Research 2025年第1期33卷 149-160页

作者： NASSER MULLA YOUSEF KAtIB ASIM M.ALMUGHAMSI DUAA S.ALKHAYAt MOHAMED MOSAAD SAMIR t.ALFOtIH RAWAN ALAOFI Department of Internal Medicine Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Radiology Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Surgery Faculty of MedicineTaibah UniversityMadinah42278Saudi Arabia Department of Endemic and Infectious Diseases Suez Canal UniversityIsmailia41522Egypt King Salman bin Abdulaziz Medical City Madinah42311Saudi Arabia Prince Mohammed Bin Abdulaziz Hospital Madinah41511Saudi Arabia

Background:Hepatocellular carcinoma(HCC)is the most common cause of cancer-related death in Saudi *** study aimed to investigate the patterns of HCC and the effect of tNM staging,Alfa-fetoprotein(AFP),and Child-turcotte Pugh(CtP)on patients’overall survival(OS).Methods:A retrospective analysis was conducted on 43 HCC patients at a single oncology center in Saudi Arabia from 2015 to *** patients had to fulfill one of the following criteria:(a)a liver lesion reported as definitive HCC on dynamic imaging and/or(b)a biopsy-confirmed ***:the mean patient age of all HCC cases was 66.8 with a male-to-female ratio of 3.3:*** patients were stratified into two groups:viral HCC(n=22,51%)and non-viral HCC(n=21,49%).Among viral-HCC patients,55%were due to HBV and 45%due to *** was diagnosed in 79%of *** and sex did not significantly statistically differ in OS among viral and non-viral HCC patients(p-value>0.05).About 65%of patients had tumor size>5 cm during the diagnosis,with a significant statistical difference in OS(p-value=0.027).AFP was>400 ng/ml in 45%of the *** was a statistically significant difference in the OS in terms of AFP levels(p-value=0.021).A statistically significant difference was also observed between the CtP score and OS(p-value=0.02).CtP class B had the longest *** was the most common treatment provided to HCC patients followed by sorafenib *** was a significant statistical difference in OS among viral and non-viral HCC patients(p-value=0.008).Conclusions:the most common predictors for OS were the underlying cause of HCC,AFP,and tumor *** having non-viral etiology,a tumor size>5 cm,an AFP>400 ng/mL,and a CtP score class C were all negatively associated with OS.

关键词： Hepatocellular carcinoma Pattern Alpha-fetoprotein(AFP) Child-turcotte-pugh Progression free survival