6: Enzyme Activity
- Page ID
- 14954
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)Return to Fundamentals of Biochemistry Search Fundamentals of Biochemistry
- 6.1: How Enzymes Work
- The page outlines the fundamental principles of enzyme catalysis, describing how enzymes lower activation energies and stabilize transition states. It emphasizes various catalytic mechanisms such as acid-base, covalent, and metal ion catalysis. The page also examines the role of enzyme structure in function, the importance of binding energy, and the interplay between thermodynamics and kinetics in enzyme reactions.
- 6.2: Kinetics without Enzymes
- This page provides a comprehensive overview of chemical kinetics, focusing on both non-enzymatic and enzymatic reactions. It explores concepts like reaction rates, rate laws, and half-lives, and explains how to write and interpret differential and integrated rate equations. The text discusses first and second-order reactions, their kinetics, and how to graphically represent and interpret them.
- 6.3: Kinetics with Enzymes
- This page provides an in-depth exploration of enzyme kinetics, focusing on learning goals such as understanding kinetic principles, the Michaelis-Menten framework, and enzyme-catalyzed reactions. It covers concepts like reaction rates, the significance of Vmax and Km, catalytic efficiency, and the use of various plots to interpret kinetic data.
- 6.4: Enzyme Inhibition
- This page explores different modes of enzyme inhibition, including reversible and irreversible inhibition. It covers competitive, uncompetitive, noncompetitive, and mixed inhibition, explaining their effects on enzyme kinetics and how they are analyzed using various plots like Michaelis-Menten and Lineweaver-Burk. It also discusses the biological significance of enzyme inhibition in pharmaceutical contexts and in vivo vs. in vitro considerations.
- 6.05A: Enzyme Reaction Mechanisms - Arrow Pushing
- This page outlines learning goals for biochemistry students on enzyme catalysis, covering mechanisms and roles of enzymes, particularly focusing on serine proteases like chymotrypsin and their catalytic strategies. It details the function of magnesium in phosphate transfer, the classification of proteases, and the mechanisms of specific enzymes like carboxypeptidase A and lysozyme.
- 6.05B: Enzyme Reaction Mechanisms - Quantiative Analyses of Serine Protease Catalysis
- This page explores enzyme mechanisms, focusing on serine proteases like chymotrypsin, and how structural, kinetic, and thermodynamic factors influence catalysis. It covers the reaction dynamics, enzyme efficiency improvements, and the effects of inhibitors and solvents on enzyme activity. Insights include the importance of conformational flexibility, the effect of nonpolar solvents for catalysis, and thermodynamic factors affecting the stability of bound and transition state analog ligands.
- 6.6: Enzymes and Protein Regulation
- The page outlines a comprehensive study on enzyme and protein regulation for advanced biochemistry students, focusing on various modes of regulation such as allosteric control, covalent modifications, and proteolytic processing. It explores the physiological and pathological states linked to enzyme dysregulation and therapeutic strategies targeting these pathways.
- 6.7: Ribozymes - RNA Enzymes
- The page provides a detailed overview of ribozymes, which are RNA molecules with catalytic properties similar to protein enzymes. It covers their structure, role in catalysis, and historical significance, emphasizing the RNA world hypothesis where RNA preceded proteins. The section examines examples like self-splicing introns, RNase P, and the ribosome as ribozymes, explaining their mechanisms and significance in evolution and cellular regulation.
- 6.8: Cofactors and Catalysis - A Little Help From My Friends
- This page provides an in-depth look at the function of cofactors in enzyme-catalyzed reactions, emphasizing their role in facilitating electron flow during chemical transformations. Cofactors are divided into two categories: metals and coenzymes, with metal cofactors often aiding in catalytic activity through electron transport and stabilization of transition states.
Thumbnail: Dihydrofolate reductase is inhibited by methotrexate which prevents binding of its substrate, folic acid. (CC BY 4.0 International; Thomas Shafee (modified) via Wikipedia)