结构生物化学Chapter8 Introduction to enzymology
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结构生物化学Chapter8 Introduction to enzymology
«What is a substrate? – A substrate is the compound that is converted into the product in an enzyme catalyzed reaction. – For the reaction catalyzed by aldolase, fructose 1,6phosphate is the substrate.
The active site of an enzyme is the place where all of the action occurs. It contains the functional groups (amino acid side chains) that bind the substrate(s) and catalyze it’s conversion to product(s).
« Enzyme catalyzed reactions are much faster than uncatalyzed reactions.
« Enzyme catalyzed reactions display saturation kinetics with respect to substrate concentration.
Active site of chymotrypsin
What does the active site do?
« The active site binds the substrates and positions them in the proper orientation for the reaction to occur.
What is Enzymes?
The active site of an enzyme is the place where all of the action occurs. It contains the functional groups (amino acid side chains) that bind the substrate(s) and catalyze it’s conversion to product(s).
« Enzyme catalyzed reactions are much faster than uncatalyzed reactions.
« Enzyme catalyzed reactions display saturation kinetics with respect to substrate concentration.
Active site of chymotrypsin
What does the active site do?
« The active site binds the substrates and positions them in the proper orientation for the reaction to occur.
What is Enzymes?
【生物化学】Chapter 6 Enzymes
1857 Louis Pasteur, fermentation of sugar into alcohol by yeast is catalyzed by “ferments.”
1897 Eduard Buchner, yeast extracts could ferment sugar to alcohol, proving that fermentation was promoted by molecules that continued to function when removed from cells. Kühne called these molecules enzymes.
efficiently and selectively Example : a bag of sugar can be stored for years, but it releases its chemical energy in seconds in human body …… “ catalysis” “ The Enzymes” the most remarkable and highly specialized proteins
Zhao Dandan
Chapter 6 Enzymes
7
(1) Biocatalysts
Produced by live cells. Typically are very large proteins. Have extraordinary catalytic power, often far
Monomeric enzyme Oligomeric enzyme Multienzyme system
Multifunctional enzyme
1897 Eduard Buchner, yeast extracts could ferment sugar to alcohol, proving that fermentation was promoted by molecules that continued to function when removed from cells. Kühne called these molecules enzymes.
efficiently and selectively Example : a bag of sugar can be stored for years, but it releases its chemical energy in seconds in human body …… “ catalysis” “ The Enzymes” the most remarkable and highly specialized proteins
Zhao Dandan
Chapter 6 Enzymes
7
(1) Biocatalysts
Produced by live cells. Typically are very large proteins. Have extraordinary catalytic power, often far
Monomeric enzyme Oligomeric enzyme Multienzyme system
Multifunctional enzyme
中国海洋大学资料生物化学课件第六章 enzyme
研究酶促反应速率，以酶促反应的初速率为准 (底物消耗≤5%）。
2、酶的活力单位（U）
① 国际单位（IU单位）
在最适反应条件下，每分钟催化 1umol底物转 化为产物所需的酶量，称一个国际单位 （IU），1 IU = 1umol /min
② 国际单位（Katal, Kat单位）
在最适反应条件下，每秒钟催化1mol底物转化 为产物所需的酶量，称Kat单位 1 Kat=60 X 106 IU
每毫克酶蛋白所具有的酶活力。 单位：U/mg蛋白质。 酶的比活力是分析酶的含量与纯 度的重要指标。
4、酶的分离纯化
① 基本原则：提取过程中避免酶变性 而失去活性；防止强酸、强碱、高 温和剧烈搅拌等；要求在低温下操 作，加入的化学试剂不使酶变性， 操作中加入缓冲溶液。
4、酶的分离纯化
② 基本操作程序：
辅酶在催化反应过程中，直接参加了反应。 每一种辅酶都具有特殊的功能，可以特定地 催化某一类型的反应。 同一种辅酶可以和多种不同的酶蛋白结合形 成不同的全酶。 一般来说，全酶中的辅酶决定了酶所催化的 类型（反应专一性），而酶蛋白则决定了所 催化的底物类型（底物专一性）。
4 单体酶、寡聚酶、多酶复合体
某些小分子有机化合物与酶蛋白结合在一起 并协同实施催化作用，这类分子被称为辅酶 （或辅基）。 辅酶是一类具有特殊化学结构和功能的化合 物。参与的酶促反应主要为氧化-还原反应或 基团转移反应。 大多数辅酶的前体主要是水溶性 B 族维生素。 许多维生素的生理功能与辅酶的作用密切相 关。
辅酶在酶促反应中的作用特点
2、米氏方程
1913年，德国化学家Michaelis和Menten根据中间产 物学说对酶促反应的动力学进行研究，推导出了表 示整个反应中底物浓度和反应速率之间定量关系的 著名公式，称为米氏方程。
生物化学 Chap 6 enzymes
Nomenclature (命名法，术语)
active site（活性部位） essential groups（必须基团） Substrate（底物） biocatalyst / catalyst/ catalyze/catalytically holoenzyme（全酶） apoenzyme（脱辅基酶蛋白） coenzyme（辅酶） cofactor（辅助因子） prosthetic group（辅基） urease/transferase/oxidoreductase（相关酶） synthase/protease
e.g. trypsin E.C.3.4.21.4
―3‖ denotes that it is a hydrolase; (大类)
―4‖ that it is a protease that hydrolyze peptide bonds; （亚类）
“21‖ that it is a serine protease with a critical serine residue at the active site; （亚亚类） “4‖ that it was the fourth enzyme to be assigned to this class. （流水编号）
clas s 1 name Oxidoreductases 氧化还原酶 Transferases 转移酶 Hydrolases 水解酶 Lyases 裂合酶 Isomerases 异构酶 Ligases/ synthases 合成酶 Type of reaction catalyzed Transfer of electrons or hydrogen AH2+B A+BH2
active site（活性部位） essential groups（必须基团） Substrate（底物） biocatalyst / catalyst/ catalyze/catalytically holoenzyme（全酶） apoenzyme（脱辅基酶蛋白） coenzyme（辅酶） cofactor（辅助因子） prosthetic group（辅基） urease/transferase/oxidoreductase（相关酶） synthase/protease
e.g. trypsin E.C.3.4.21.4
―3‖ denotes that it is a hydrolase; (大类)
―4‖ that it is a protease that hydrolyze peptide bonds; （亚类）
“21‖ that it is a serine protease with a critical serine residue at the active site; （亚亚类） “4‖ that it was the fourth enzyme to be assigned to this class. （流水编号）
clas s 1 name Oxidoreductases 氧化还原酶 Transferases 转移酶 Hydrolases 水解酶 Lyases 裂合酶 Isomerases 异构酶 Ligases/ synthases 合成酶 Type of reaction catalyzed Transfer of electrons or hydrogen AH2+B A+BH2
结构生物化学Chapter9 Enzyme kinetics
The theoretical maximal velocity @ Vmax is a constant @ Vmax is the theoretical maximal rate of the reaction - but it is
NEVER achieved in reality @ To reach Vmax would require that ALL enzyme molecules are
k1 Et k1ES S (k1 k2 )ES k1 Et S ES (k1S (k1 k2 ))
ES
k1Et S (k1S (k1
k2 ))
S
Et S
(k1 k2 ) k1
Km (k1k2) k1 ES
Et S S Km
@ Rate of production formation (rate law), v = k2[ES]. So:
v f vd
Derivation of Michaelis-Menten Equation
@ We need one more condition, that is, the total enzyme concentration, [Et] is the sum of that of enzyme-substrate complex, [ES], and that of free enzyme, [E]:
Chapter 9 Enzyme Kinetics
Outline
@ Definition of enzyme kinetics @ Factors affecting enzyme-catalyzed reactions @ Michaelis-Menten Kinetics @ Enzyme inhibition kinetics @ Allosteric enzyme kinetics
NEVER achieved in reality @ To reach Vmax would require that ALL enzyme molecules are
k1 Et k1ES S (k1 k2 )ES k1 Et S ES (k1S (k1 k2 ))
ES
k1Et S (k1S (k1
k2 ))
S
Et S
(k1 k2 ) k1
Km (k1k2) k1 ES
Et S S Km
@ Rate of production formation (rate law), v = k2[ES]. So:
v f vd
Derivation of Michaelis-Menten Equation
@ We need one more condition, that is, the total enzyme concentration, [Et] is the sum of that of enzyme-substrate complex, [ES], and that of free enzyme, [E]:
Chapter 9 Enzyme Kinetics
Outline
@ Definition of enzyme kinetics @ Factors affecting enzyme-catalyzed reactions @ Michaelis-Menten Kinetics @ Enzyme inhibition kinetics @ Allosteric enzyme kinetics
生化chapter+08-10+enzyme-01
1891-1987
Wendell Meredith Stanley
1/4 of the prize
Rockefeller Institute for Medical Research Princeton, NJ, USA
1904-1971
Urease crystals ( X 728)
Sumner, J. B. (1926) “ The isolation and crystallization of the
4、酶是活细胞产生的，能在细胞内外起催化作用的生理活性物质。 那么酶的化学本质究竟是什么？
1926年,美国康乃尔大学的Sumner博士从刀豆中提取出脲酶结晶， 并证明具有蛋白质的性质。
1930年，美国的生物化学家Northrop分离得到了胃蛋白酶 （pepsin）、胰蛋白酶（trypsin）、胰凝乳蛋白酶 （chymotrypsin）结晶，确立了酶的化学本质。
can be
crystallized"
James Batcheller Sumner
1/2 of the prize Cornell University Ithaca, NY, USA
1887-1955
John Howard Northrop
1/4 of the prize
Rockefeller Institute for Medical Research Princeton, NJ, USA
III、 水解酶类：催化加水分解作用。
AB + H2O
AOH + BH
该大类酶的系统命名是先写底物名称，再写发生水解作用的化 学键位置，后面加上“水解酶”
IV、裂解酶类：催化非水解性地除去基团而形成双键的反应或逆 反应。
Wendell Meredith Stanley
1/4 of the prize
Rockefeller Institute for Medical Research Princeton, NJ, USA
1904-1971
Urease crystals ( X 728)
Sumner, J. B. (1926) “ The isolation and crystallization of the
4、酶是活细胞产生的，能在细胞内外起催化作用的生理活性物质。 那么酶的化学本质究竟是什么？
1926年,美国康乃尔大学的Sumner博士从刀豆中提取出脲酶结晶， 并证明具有蛋白质的性质。
1930年，美国的生物化学家Northrop分离得到了胃蛋白酶 （pepsin）、胰蛋白酶（trypsin）、胰凝乳蛋白酶 （chymotrypsin）结晶，确立了酶的化学本质。
can be
crystallized"
James Batcheller Sumner
1/2 of the prize Cornell University Ithaca, NY, USA
1887-1955
John Howard Northrop
1/4 of the prize
Rockefeller Institute for Medical Research Princeton, NJ, USA
III、 水解酶类：催化加水分解作用。
AB + H2O
AOH + BH
该大类酶的系统命名是先写底物名称，再写发生水解作用的化 学键位置，后面加上“水解酶”
IV、裂解酶类：催化非水解性地除去基团而形成双键的反应或逆 反应。
【生物化学精品】Chapter8 Introduction to enzymology
What is Enzymes?
Enzymes are biological catalysts that accelerate the rates of chemical reactions.
Snail without enzyme catalyst
Snail with enzyme catalyst
Enzyme catalyzed reaction
D[Product] Reaction Rate = D(time)
[Product]
Uncatalyzed
reaction
0
0
Time
Enzyme catalyzed reactions display saturation kinetics with respect to reactant concentration
What is a substrate? A substrate is the compound that is converted into the product in an enzyme catalyzed reaction. For the reaction catalyzed by aldolase, fructose 1,6phosphate is the substrate.
Enzyme catalyzed reactions are much faster than uncatalyzed reactions.
Enzyme catalyzed reactions display saturation kinetics with respect to substrate concentration.
Substrates, products, and enzymes
《生物化学讲义总纲》PPT课件
2020/11/18
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▪ 3.糖的种类： 单糖：定义 ：最简单的糖/不能水解为更简单的糖的糖类。醛糖、 酮糖 、 丙、丁、戊、己、庚糖及其两者的组合。重要单糖的举例：葡萄糖（己 醛糖）、果糖（己酮糖）、核糖和脱氧核糖（戊醛糖）
▪ 寡糖：定义：由2-6个单糖通过糖苷键形成的糖类/能水解为2-6个单糖的 糖类。举例：蔗糖（葡-果）、麦芽糖（葡-葡）、乳糖（葡-半）。
反应部位
主体、配体、糖苷键的键型（半缩醛羟基的构型-半缩醛 羟基的位置，另一羟基的位置，如：α-1,4 ）
全名：配体-糖苷键型-主体苷
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▪ <3>.糖的还原性 费林反应（Fehling）：费林试剂（碱性的铜络合物） 反应式 定 量法（Cu2O） 还原糖：能使Cu2+还原的糖类，醛糖和酮糖都是还原糖。
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§2.甘油脂 定义：高级脂肪酸与甘油，其中甘油三脂就是油脂。 一.脂肪酸：结合态、游离态（FFA） 1.性质 ▪ 偶数：16，18，20，22，24 ▪ 顺式 ▪ 双键的位置：9、12、15 ▪ 溶点与结构的关系：链长（长-高），饱和度（饱-高） 2.简单表达式： ▪ 简单结构式：波浪形，注意双键的构型 ▪ 简单表达式：链长：双键数△双键位置 ▪ 举例：油酸18：1△9
0.03％ 1％
36％
63％
+112.20
+18.70
2020/11/18
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▪ 5.葡萄糖的构象：船式和椅式，用模型显示。 6.几种重要单糖的结构式（默认为D-型）：甘油醛 二羟丙 酮 核糖 脱氧核糖 葡萄糖 甘露糖 半乳糖 果糖链式和 环式都要，请大家自己在书上将其找到，作为家庭作业。
生物化学(英文版)biochemistry-chapter 1英文1
In 1828 ， F.WÖ hler (Germany Chemist，1800-1882）showed by synthesizing urea from ammonium cyanate that compounds found in living organisms could be made in the laboratory from inorganic substrances.Accordingly,he rejected the “Vitalism theory”
In 1883, Anselme Payen (French chemist) discover Amylase.“-ase” was postfix of enzymes. He isolated Cellulose and named it .“-ose” was postfix of carbohydrates.
1780s Antoine Laurent Lavoisier (French): Combustion of a candle is similar to the “respiration ”of animals, as both need O2 . For the first time a physiological process was explained with reference to a nonliving mechanism. Disaffirming “The Phlogiston Theory”
introducechemicalactionscourseslivingsystemsmetabolismproteinproteinenzymeenzymecarbohydratecarbohydratelipidlipidnucleicacidnucleicacidvitaminvitaminhormonehormonestaticbiochemistrydynamicbiochemistrymetabolismenergymetabolismenergycarbohydratemetabolismcarbohydratemetabolismlipidmetabolismlipidmetabolismproteinmetabolismproteinmetabolismnucleicacidmetabolismnucleicacidmetabolismgeneticinformationtransmissiongeneticinformationtransmissioncontentsbiochemistrycontentstextbooksprinciplesbiochemistryprinciplesbiochemistry3rdeditionhrhorton等主编科学出版社20034生物化学第三版生物化学第三版王镜岩朱圣庚等主编高等教育出20029chapterbiochemistrychapterbiochemistry11briefhistorybiochemistry11briefhistorybiochemistry1212whatanswer
生物化学第8章PPT课件
33
脂肪酸的-氧化(第4步反应)
34
脂肪酸的-氧化小结
脂肪酸氧化的主要反应
36
软脂酸的β-氧化
37
Summarization of FA -oxidation
1．FA仅需活化一次，消耗1ATP的两个高能 磷酸键，活化的酶在线粒体膜外；
2．Acryl CoA（长链）需经肉碱运输才能进 入线粒体内，有肉碱转移酶I和II；
52
FA的-氧化途径
53
九、过氧化物酶体的β-氧化
线粒体是脂肪酸氧化的主要场所， 但一定细胞的特定膜结构也会氧 化脂肪酸，过氧化物酶体 (Peroxisomes)可以以与线粒 体相似但不完全相同的方式氧化 脂肪酸。
54
九、过氧化物酶体的β-氧化 过氧化物酶体氧化脂肪酸四步反
应的第一步黄素蛋白脱氢酶催化 脱氢生成FADH2，电子直接传递 给O2生成H2O2，后者被过氧化氢 酶分解解毒。
2-烯脂酰 CoA——→ -羟脂酰CoA
H2O
29
脂肪酸的-氧化(第2步反应
30
脂肪酸的-氧化(第3步反应)
3. 再脱氢：L(+)-羟脂酰CoA脱氢， 生成-酮脂酰CoA，由脱氢酶催化，酶 以NAD+为辅酶，只对L型底物有作用；
-羟脂酰CoA--羟-脂-酰-Co-A脱-氢→酶 -酮脂酰CoA
20
二、脂肪酸的活化（续）
脂肪酸+
ATP+
脂酰CoA合成酶
HS-CoA
脂酰CoA+ AMP+PPi
R-COO- +ATP+HS-CoA R-CO-SCoA+AMP+PPi(2Pi)
21
脂肪酸转变为脂酰-CoA
脂肪酸的-氧化(第4步反应)
34
脂肪酸的-氧化小结
脂肪酸氧化的主要反应
36
软脂酸的β-氧化
37
Summarization of FA -oxidation
1．FA仅需活化一次，消耗1ATP的两个高能 磷酸键，活化的酶在线粒体膜外；
2．Acryl CoA（长链）需经肉碱运输才能进 入线粒体内，有肉碱转移酶I和II；
52
FA的-氧化途径
53
九、过氧化物酶体的β-氧化
线粒体是脂肪酸氧化的主要场所， 但一定细胞的特定膜结构也会氧 化脂肪酸，过氧化物酶体 (Peroxisomes)可以以与线粒 体相似但不完全相同的方式氧化 脂肪酸。
54
九、过氧化物酶体的β-氧化 过氧化物酶体氧化脂肪酸四步反
应的第一步黄素蛋白脱氢酶催化 脱氢生成FADH2，电子直接传递 给O2生成H2O2，后者被过氧化氢 酶分解解毒。
2-烯脂酰 CoA——→ -羟脂酰CoA
H2O
29
脂肪酸的-氧化(第2步反应
30
脂肪酸的-氧化(第3步反应)
3. 再脱氢：L(+)-羟脂酰CoA脱氢， 生成-酮脂酰CoA，由脱氢酶催化，酶 以NAD+为辅酶，只对L型底物有作用；
-羟脂酰CoA--羟-脂-酰-Co-A脱-氢→酶 -酮脂酰CoA
20
二、脂肪酸的活化（续）
脂肪酸+
ATP+
脂酰CoA合成酶
HS-CoA
脂酰CoA+ AMP+PPi
R-COO- +ATP+HS-CoA R-CO-SCoA+AMP+PPi(2Pi)
21
脂肪酸转变为脂酰-CoA
生物化学英文课件Chapter6 Mechanisms of Enzymes
➢ The rate-determining step (rate-limiting step) —— the step with the highest energy transition state.
➢ Catalysts participate directly in reactions by stabilizing the transition states.
Oxidation-reduction reactions
• Electrons are transferred between two species • Oxidizing agent gains electrons (is reduced) • Reducing agent donates electrons (is oxidized) • Formaldehyde is oxidized by oxygen (below) and oxygen is
• Carbocation formation – one electron stays with one atom
• Free radical formation – one electron remains with each
product to form 2 free radicals which are unstable
6.2 Catalysts stabilize transition states
➢ The rate of a chemical reaction depends on how often reacting molecules collide in such a way that a transition state is formed.
➢ Catalysts participate directly in reactions by stabilizing the transition states.
Oxidation-reduction reactions
• Electrons are transferred between two species • Oxidizing agent gains electrons (is reduced) • Reducing agent donates electrons (is oxidized) • Formaldehyde is oxidized by oxygen (below) and oxygen is
• Carbocation formation – one electron stays with one atom
• Free radical formation – one electron remains with each
product to form 2 free radicals which are unstable
6.2 Catalysts stabilize transition states
➢ The rate of a chemical reaction depends on how often reacting molecules collide in such a way that a transition state is formed.
01结构生物化学
第一章氨基酸1氨基酸的分类书p6、7目前已发现的蛋白质氨基酸有22种，其中最早发现的20种比较常见。
两种不常见的蛋白质氨基酸：硒代半胱氨酸（Sec，U）——只存在于含硒蛋白之中，例如谷胱甘肽过氧化物酶体和一种参与含有3个碘原子的甲状腺素合成的去碘酶。
人体缺硒就会影响到其体内所有需要硒代半胱氨酸的蛋白质合成，从而导致相应的缺乏症。
*克山病，由缺硒造成。
吡咯赖氨酸（Pyl，O）——在自然界中十分罕见，仅存在于一些产甲烷的古菌，以及某些革兰阳性细菌的厚壁细菌和δ-变形细菌体内。
而在产生甲烷的古菌体内，只有催化甲烷合成的酶分子中才有它。
✦根据氨基酸R基团的化学结构分类：（1）非极性的脂肪族氨基酸6’包括甘、丙、缬、亮、异亮、脯。
这些氨基酸的侧链都不能与水分子形成氢键，所以是非极性的。
甘氨酸：最小的氨基酸，是22种蛋白质氨基酸中唯一没有手性的。
脯氨酸：实际上是一种亚氨基酸，其侧链与亚氨基形成一个刚性的环，它和Gly一样通常会造成多肽链的弯曲。
（2）芳香族氨基酸（非极性）3’包括苯丙、酪、色。
它们的R基团都含有苯环，但极性差别很大，极性的差别是由苯环上的取代基团造成的。
极性由强到弱：Tyr＞Trp＞Phe（3）不带电荷的极性氨基酸6’包括丝、苏、天冬酰胺、谷氨酰胺、半胱氨酸、甲硫氨酸。
丝氨酸、苏氨酸：R基团含有极性的羟基。
天冬酰胺、谷氨酰胺：分别是天冬氨酸、谷氨酸发生酰胺化反应的产物，它们的R基团含有极性的酰胺基。
半胱氨酸、甲硫氨酸：R基团含有S原子，其中Cys含有巯基，其pKa约为8.4，在生理pH下主要以非解离的形式存在。
溶液中游离的Cys分子之间可以发生氧化还原反应形成二硫键，由此形成一种非蛋白质氨基酸——胱氨酸。
Met在代谢中的重要作用与S原子上的甲基有关，它受到刺激后，可作为甲基供体参与多种生物分子的甲基化修饰，例如DNA、RNA和组蛋白的甲基化。
（4）带电荷的极性氨基酸7’包括天冬、谷、硒代半胱氨酸、组、赖、吡咯赖氨酸、精。
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Enzyme catalyzed reactions display saturation kinetics with respect to reactant concentration
Important things to remember about enzymes just like other catalysts
1. Enzymes are not consumed or altered by the reaction they catalyze.
? Just as a construction worker can take being physically changed by the proc them into products without being physic
1. Higher reaction rates: The rates of enzym
processes are accele8-r1 1 a. 00 ted by a Example1: carbonic anhydrase catalyzes: CO2 +H2O? H2CO3 nonenzymatic rate constant = 1.3 x 10-1 s-1 enzymatic rate constant = 1 x 106 s-1 (x 7.7 x 106) Example2: Staphylococcal nuclease catalyzes nucleic acid hydrolysis nonenzymatic rate constant = 1.7 x 10-13 s-1 enzymatic rate constant = 95 s-1 (x 5.6 x 1014)
? At equilibrium, the ratio of substrate whether an enzyme catalyst is present. of reactants to products is not altered is achieved is increased.
General Properties of Enzymes
2. Enzymes catalyze both the forward and the reverse reaction.
? This is an important podientt. ermiAnne ewnhziycmhe the reaction goes, it only increases t equilibrium.
Chemical nature of enzymes
? All enzymes are proteins exce proteins are enzymes
? It was assumed that all enzyme when Thomas Cech and Sydney Al catalytic RNAs (Nobel prize in
Enzyme catalyzed reactions are much faster than uncatalyzed reactions
Enzyme catalyzed r eaction
[Product]
D[Product]
Reaction Rate = D(time)
Uncatalyzed
reaction
Enzyme
Substrates
Product
Enzymes catalyze the conversion of substrates into roducts
?What is a substrate? A substrate is the compound product in an enzyme cata For the reaction catalyze phosphate is the substrate.
Chapter 8 Introduction to Enzymology
Outline
?What is enzyme? ?Chemical nature of enzymes ?Catalytic properties of enz
-Features shared by enzyme catalysts -Unique features of enzymes ?Classification and nomenclat
? Enzyme catalyzed reactions ar uncatalyzed reactions.
? Enzyme catalyzed reactions di with respect to substrate conce
? Enzyme catalyzed reactions ar temperature and pH values.
Enzymes catalyze both the reactions in both the forward and reverse direction
LDH LDH
3. Enzymes do not alter the equilibrium (or equilibrium constant) between substrates and products.
What is Enzymes?
?Enzymes are biological ca
the rates of c. hemical rea
Snail without enzyme catalySstnail with enzym
Substrates, products, and enzymes
Enzymes catalyze the rate converted to product
? Catalytic RNA, or ribozymes, s criteria: substrate specificity emerge from reaction unchang
The difference between enzyme catalyzed & uncatalyzed chemical reactions