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z - CHM040 - Biomolecules > Chapter 4: Enzymes > Flashcards

Chapter 4: Enzymes Flashcards

1
Q
  • effective catalysts for an enormous diversity of chemical reactions
  • bring substrates together in an optimal orientation
  • catalyze reactions by stabilizing transition states
A

enzymes

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2
Q

how do enzymes determine which one of several potential chemical reactios actually takes place

A

selectively stabilizing a transition state

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3
Q
  • additional chemical component
  • one or more inorganic ions
A

cofactor

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4
Q

complex organic or metalloorganic molecule

A

coenzyme

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5
Q

examples of inorganic ions

A
  • Fe2+
  • Mg2+
  • Mn2+
  • Zn2+
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6
Q

Coenzyme that transfers CO2

A

biocytin

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7
Q

Coenzyme that transfers acyl groups

A

coenzyme A

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8
Q

Coenzyme that transfers H atoms and alkyl groups

A

5’-Deoxyadenosylcobalamin (coenzyme B12)

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9
Q

Coenzyme that transfers electrons

A

Flavin adenine dinucleotide

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10
Q

Coenzyme that transfers electrons and acyl groups

A

Lipoate

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11
Q

Coenzyme that transfers hydride ion (:H-)

A

nicotinamide adenine dinucleotide

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12
Q

Coenzyme that transfers amino groups

A

pyridoxal phosphate

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13
Q

Coenzyme that transfers one-carbon groups

A

tetrahydrofolate

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14
Q

Coenzyme that transfers aldehydes

A

thiamine pyrophosphate

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15
Q

provide additional chemically reactive functional groups besides those present in the amino acid chains of apoenzymes

A

cofactors

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16
Q

are sythesized within the human body using building blocks obtained from other nutrients

A

coenzymes

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17
Q

coenzyme or metal ion that is very tightly or even covalently bound to enzyme protein

A

prosthetic group

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18
Q

complete, catalytically active enzyme together with its bound coenzyme and/or metal ions

A

holoenzyme

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19
Q

protein part of enzyme

A

apoenzyme or apoprotein

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20
Q

permanent attachment is __ an absolute requirement for coenzyme to be an active part of enzyme

A

NOT

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21
Q

provides an example of coenzyme behavior where it is released after reaction has occured

A

NAD+

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22
Q

how are some enzyme protein modified covalently

A

by
- phosphorylation
- glycosylation
- other processes

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23
Q

Which of the following statements about conjugated enzyme is correct?

a. it contains only amino acids
b. it always contains a metal atom
c. it always contains a nonprotein part
d. no correct response

A

c. it always contains a nonprotein part

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24
Q

Which of the following statements about cofactors is incorrect?

a. all conjugated enzymes contain cofactors
b. metal ions can function as cofactors
c. coenzyme is an alternate name for all cofactors
d. no correct response

A

c. coenzyme is an alternate name for all cofactors

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25
Q

Which of the following statements about the interaction of cofactors with apoenzymes is correct?

a. they are always covalently bonded to the apoenzyme
b. they cannot be covalently bonded to the apoenzyme
c. they can, but do not have to be, covalently bonded to the apoenzyme
d. no correct response

A

c. they can, but do not have to be, covalently bonded to the apoenzyme

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26
Q

sugar that can be stored indefinitely on the shelf with no deterioration

A

glucose

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27
Q

what does glucose represent

A

thermodynamic potentiality

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28
Q

suffix that identifies substance as an enzyme

A

-ase
-in

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29
Q

examples of enzymes with -ase

A
  • urease
  • sucrase
  • lipase
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30
Q

examples of enzymes with -in

A
  • trypsin
  • chymotrypsin
  • pepsin
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31
Q

catalyzes an oxidation reaction

A

oxidase enzyme

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32
Q

catalyzes a hydrolysis reaction

A

hydrolase enzyme

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33
Q

catalyzes the oxidation of glucose

A

glucose oxidase

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34
Q
A
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35
Q

catalyzes the carboxylation of pyruvate

A

pyruvate carboxylase

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35
Q

refers to the chemical reaction in which carboxylic acid groups are produced by treating the substrate with carbon dioxide

A

Carboxylation

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35
Q

catalyzes the dehydrogenation of succinate

A

succinate dehydrogenase

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35
Q

catalyzes the hydrolysis of urea

A

urease

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36
Q

catalyzes the hydrolysis of lactose

A

lactase

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37
Q

Predict function of enzyme:
cellulase

A

catalyzes hydrolysis of cellulose

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38
Q

Predict function of enzyme:
sucrase

A

catalyzes hydrolysis of disaccharide sucrose

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39
Q

Predict function of enzyme:
L-Amino acid oxidase

A

catalyzes the oxidation of L-amino acids

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40
Q

Predict function of enzyme:
aspartate aminotransferase

A

catalyzes transfer of amino group from aspartate to different molecule

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41
Q

Six major classes of enzymes on the basis of types of reactions they catalyze

A
  1. oxidoreductase
  2. transferase
  3. hydrolase
  4. lyase
  5. isomerase
  6. ligase
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42
Q

catalyzes an oxidation-reduction reaction

A

oxidoreductase

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43
Q

oxidation reaction

A

increase C-O
decrease C-H

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44
Q

reduction reaction

A

decreases C-O
increases C-H

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45
Q

what do fruits contain that makes it oxidize

A

phenol derivatives

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46
Q

Ways which can prevent or slow down phenolase and enzymatic browning

A
  1. immersion in cold water
  2. refrigiration
  3. boiling
  4. addition of lemon juice
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47
Q

catalyzes transfer of functional group from one molecule to another

A

transferase

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48
Q

two major subtypes of transferase

A
  1. transaminase
  2. kinases
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49
Q

transfer of amino group from one molecule to another

A

transaminase

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50
Q

transfer of phosphate group from adenosine triphosphate (ATP) to give adenosine diphosphate (ADP)

A

kinases

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51
Q

calatyzes reaction between glutamine residue in protein and lysine residue

A

transglutaminases

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52
Q

can be used to make consistent, uniform portions of meat or fish from smaller scraps

A

meat glue

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53
Q

catalyzes hydrolysis reaction in which addition of water molecule causes bond to break

A

hydrolase

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54
Q

what doe pineapply, kiwi, or papaya have that prevents hydrogel from forming

A

protease (ligase)

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55
Q

Protease of fress pineapple

A

bromelain

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56
Q

Protease of fresh kiwi

A

actinidin

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57
Q

Protease of fresh papaya

A

papain

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58
Q

what do the protease of the fresh fruits hydrolyze

A

hydrolysis of peptide (amide) linkages in gelatin

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59
Q

catalyzes the addition of a group to a double bond or the removal of a group to form a double bond in a manner that does not require hydrolysis or oxidation

A

Lyase

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60
Q

example of groups that are removed by Lyase when forming double bonds

A
  • H2O
  • CO2
  • NH3
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61
Q

catalyzes the isomerization of a substrate in a reactio, converting it into a molecule isomeric with itself

A

isomerase

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62
Q

catalyzes the bonding together of two molecules into one wth the participation of ATP

A

ligase

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63
Q

subclasses of oxidoreductase

A
  1. oxidases
  2. reductases
  3. dehydrogenases
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64
Q

oxidation of substrate

A

oxidase

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65
Q

reduction of substrate

A

reductase

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66
Q

introduction of double bond (oxidation) by formal removal of two H atoms from a substrate, with one H being accepted by a coenzyme

A

dehydrogenases

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67
Q

subclasses of transferases

A
  1. transaminase
  2. kinase
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68
Q

transfer of an amino group between substrates

A

transaminase

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69
Q

transfer of phosphate group between substrates

A

kinase

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70
Q

subclasses of hydrolases

A
  1. lipase
  2. protease
  3. nuclease
  4. carbohydrase
  5. phosphatase
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71
Q

hydrolysis of ester linkages in lipids

A

lipase

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72
Q

hydrolysis of amide linkages in proteins

A

protease

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73
Q

hydrolysis of sugar-phosphate ester bonds in nucleic acids

A

nuclease

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74
Q

hydrolysis of glycosidic bonds in carbohydrates

A

carbohydrase

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75
Q

hydrolysis of phosphate-ester bonds

A

phosphatase

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76
Q

subclasses of lyase

A
  1. dehydratase
  2. decarboxylase
  3. deaminase
  4. hydratase
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77
Q

removal of H20 from substrate

A

dehydratase

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78
Q

removal of CO2 from substrate

A

decarboxylase

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79
Q

removal of NH3 from substrate

A

deaminase

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80
Q

addition of H2O to a substrate

A

hydratase

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81
Q

subclasses of isomerase

A
  1. racemase
  2. mutase
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82
Q

conversion of D isomer to L isomer or vice versa

A

racemase

83
Q

transfer of functional group from one position to another in the same molecule

A

mutase

84
Q

subclasses of ligase

A
  1. synthetase
  2. carboxylase
85
Q

formation of new bond between two substrates, with participation of ATP

A

synthetase

86
Q

formation of new bond between a substrate and CO2 with participatioin of ATP

A

carboxylase

87
Q

Which of the following paiings of enzyme type and enzyme function is incorrect?

a. lipase - hydrolysis of ester linkages
b. hydratase - addition of water to substrate
c. carboxylase - removal of carbon dioxide from substrate
d. no correct response

A

c. carboxylase - removal of carbon dioxide from substrate

88
Q

Which of the following pairings of enzyme type and enzyme function is incorrect?

a. kinase - transfer of phosphate group between substrates
b. mutase - introduction of double bond withing a molecule
c. protease - hydrolysis of amide linkages in a protein d. no response

A

b. mutase - introduction of double bond withing a molecule

89
Q
  • thermodynamic property that is a measure of useful energy
  • energy that is capable of doing work
A

Gibbs Free Energy (G)

90
Q

two thermodynamic properties of the reaction in order to understand how enzymes operate

A
  1. free-energy difference (ΔG) between the products and reactants
  2. energy required to initiate conversion of reactants into products (Ea)
91
Q

what does the free-energy change provide information about

A

spontaneity NOT rate of reaction

92
Q

The free-energy change of reaction (ΔG) tells us if reaction can take place spontaneously:

A
  1. ΔG<0 : reaction can take place
  2. ΔG=0 : equilibrium, no net change can take place
  3. ΔG>0 : reaction cannot take place
  4. ΔG of a reaction is independent of molecular mechanism
  5. rate of reaction depends on free energy activation (∆G‡)
93
Q

ΔG<0 reactions

A

exergonic

94
Q

ΔG>0 reactions

A

endergonic

95
Q

what drives ΔG>0 reactions

A

input of free energy

96
Q

how do enzymes speed up chemical reactions

A
  • changes path by which reaction occurs
  • lowering activation energy
97
Q

∆G

A

difference in free energy between the products and the reactants

98
Q

what do enzymes alter

A

reaction rate, not reaction equilibrium

99
Q

denotes the transition state

A

X‡

100
Q

∆G‡

A

activation energy

101
Q

X‡ denotes the transition state:

A
  1. transitory molecule no longer substrate but not yet product
  2. least-stable, most-seldom occupied species along reaction pathway because it has highest free energy
102
Q

what is the first step in enzymatic catalysis

A

formation of enzyme-substrate compex

103
Q

why do enzymes bind to and then alter the structure of substrate

A

promote formation of transition state

104
Q

formula for ∆G‡

A

X‡ (transition state) - ∆G (free energy)

105
Q

Evidence for existene of enzyme-substrate complex

A
  1. constant concentration of enzyme, reaction rate increases with increasing substrate concentration until maximal velocity is reached
  2. spectrosocopic characteristics of many enzymes and substrates change on formation of ES complex
  3. x-ray crystallography
106
Q

Common Features of Active Sites of Enzymes

A
  1. 3D cleft formed by groups from different parts of amino acid sequence
  2. takes up small part of total volume
  3. unique microenvironments
  4. substrates are bound to enzyme by multiple weak attractions
  5. Specificity of binding depends on precisely defined arrangements of atoms in active site
107
Q

Two types of Mechanism of Enzyme Action

A
  1. Emil-Fischer’s Lock-and-Key Mechanism
  2. Koshland Induced-fit Mechanism
108
Q
  • enzymes and substrates combine due to having complementary geometries
  • enzyme is pictured as being conformationally rigid
  • explains specificity of enzyme
  • not all have specific shapes for lock-and-key
A

Emil-Fischer’s Lock-and-Key Mechanism

109
Q
  • substrate induces conformational change resulting in complementary interaction
  • protein does not have complementary binding site
A

Koshland Induced-fit Mechanism

110
Q

intermediate reaction species formed when substance binds to active site of enzyme

A

Enzyme-substance (ES) complex

111
Q
  • free energy released on binding
  • free energy released from the formation of large number of weak interactions between complementary enzyme and its substrate
A

binding energy

112
Q

correct substrate participate in most or all interactions with enzyme

A

maximize binding energy

113
Q

enzyme facilitates formation of transition state

A

maximal binding energy

114
Q

formed only when substrate is converted into transition state

A

full complement of such interactions

115
Q

happens when energy is released by interaction between enzyme and substrate

A

lowering activation energy

116
Q

state in which substrate is in an energetically unstable form, having features of both substrate and product

A

transition state

117
Q

Kinds of Transition State Changes

A
  1. enzyme put stress on bond promoting breakage
  2. enzyme may facilitate reaction by bringing two reactants close together and in proper orientation
  3. active site of enzyme may modify pH of microenvironment
118
Q

Six steps in HIV protease inhibitor and pharmaceutical drug design

A
  1. binding
  2. fusion
  3. reverse transcription
  4. integration
  5. replication
  6. assembly
119
Q

ability of an enzyme to select a specific substrate from a range of chemically similar compounds

A

enzyme specificity

120
Q

Types of Enzyme Specificity

A
  1. absolute specificity
  2. group specificity
  3. linkage specificity
  4. stereochemical specificity
121
Q
  • enzyme will catalyze only one reaction
  • most restrictive
  • not common
A

absolute specificity

122
Q

Ex. of absolute specific enzymes

A
  1. Aminoacyl tRNA synthetase
  2. Catalase
123
Q
  • selectivity is achieved by binding to a pocket in catalytic site
  • correct amino acid has the highest binding affinity for the binding pocket
A

Aminoacyl tRNA synthetase

124
Q
  • catalyzes conversion of hydrogen peroxide and water
  • hydrogen peroxide is the only substrate it will accept
A

catalase

125
Q

enzyme will act only on molecules that have specific functional group, such as hydroxyl, amino, or phosphate groups

A

group specificity

126
Q

Ex. of group specific enzymes

A
  1. carboxypeptidase
  2. hexokinase
127
Q

cleaves amino acids, one at a time, from carboxyl end

A

carboxypeptidase

128
Q
  • catalyzes addition of phosphoryl group to hexose sugar gluose in first step of glycolysis
  • can also add phosphoryl group to several other six-carbon sugars
A

hexokinase

129
Q

enzyme will act on particular type of chemical bond, irrespective of the rest of molecular structure

A

linkage specificity

130
Q

Ex. of linkage specific enzymes

A
  1. phosphatase
  2. protease
131
Q

hydrolyze phosphate-ester bonds in all types of phosphate ester

A

phosphatase

132
Q

hydrolyze peptide bonds

A

protease

133
Q
  • enzyme act on particular stereoisomer
  • chirality is inherent in anenzyme active site
  • I-amino acid oxidase will catalyze oxidation of L-form of an amino acid but not D-form of same amino acid
A

stereochemical specificity

134
Q

QUICK QUIZ:
specificity of enzyme that catalyzes the oxidation of several different alcohols is termed as __

A

group specificity

135
Q

QUICK QUIZ:
linkage-specific enzymes will act on a particular type of __

A

chemical bond

136
Q

measure of rate at which an enzyme converts substrate to products in a biochemical reaction

A

enzyme activity

137
Q

Four factors that affect enzyme activity

A
  1. temperature
  2. pH
  3. substrate concentration
  4. enzyme concentration
138
Q

measure of kinetic energy of molecules

A

temperature

139
Q

as temperature of enzymatically catalyzed reaction__, so does the __ of reaction

A
  • increases
  • rate (velocity)
140
Q

optimum temperature for human enzymes

A

37C

141
Q

temperature of autoclave

A

121C

142
Q

when does water starts to boil

A

atmospheric pressure = vapor pressure

143
Q
  • where charge on acidic and basic amino acids
  • enzyme exhibit maximum activity in its optimum measurement
A

pH

144
Q

small changes in __ can result in enzyme denaturation

A

pH

145
Q
  • suicide bags
  • degrade large biological molecules into small molecules
A

lysosomes

146
Q
  • new molecule of substrate cannot bind to the enzyme molecule until substrate molecule already held in active site is converted to product and released
  • reaction is dependent on amount of enzyme that is available
A

substrate concentration

147
Q

Two stages of enzyme-catalyzed reaction

A
  1. formation of enzyme-substrate complex
  2. conversion of substrate into product and release of product and enzyme
148
Q

formation of enzyme-substrate complex

A

binding of substrate to active site is rapid

149
Q

conversion of substrate into product and release of product and enzyme

A

step is slower and limits the rate of overall reaction

150
Q

number of substrate molecules transformed per minute by one molecule of enzyme under optimum conditions

A

enzyme’s turnover number

151
Q
  • cell usually keep amount of enzyme low compared to no. of substrate
  • concentration of substrate in reaction is higher than enzyme
A

enzyme concentration

152
Q

why does the cell keep amount of enzyme low compared to substrate

A

avoid paying energy costs

153
Q

what happens if the no. of enzymes increases while no. of substrate is constant

A

reaction rate is increased because more substrate are accomodated

154
Q

microorganism that thrives in extreme environments

A

extremophile

155
Q

microbial enzyme active at conditions that would inactivate enzymes present in other types of higher organisms

A

extremozymes

156
Q

Ex. of extremophiles

A
  1. acidophile
  2. alkaliphile
  3. halophile
  4. hyperthermophile
  5. piezophile
  6. xerophile
  7. cryophile
157
Q

Industrial Use of Extremozymes Process

A
  1. extremophile samples gathered
  2. DNA material extracted and processed
  3. macroscopic amounts of DNA produced using polymerase chain reaction
  4. produced macroscopic DNA analyzed to find genes present involved in extremozyme production
  5. genetic engineering used to insert gene to bacteria to produce extremozyme
  6. process commercialized
158
Q

QUICK QUIZ:
number of substrate molecules converted to product per minute is a measure of ____

A

enzyme activity

159
Q

QUICK QUIZ:
plot of enzyme activity (y-axis) versus pH (x-axis) with other variables constant is a

A

line with upward slope followed by downward slope

160
Q

QUICK QUIZ:
plot of enzyme activity (y-axis) verus temperature (x-axis) with other variables constant

A

line with upward slope followed by downward slope

161
Q

energy conservation

A

regulation of enzyme activity

162
Q

ex. of regulation of enzyme activity

A
  1. cell continually produce large amounts of enzyme, substrate concentration low = production of enzyme turned off
  2. product of enzyme-catalyzed reaction present is plentiful (moer than needed) = enzyme needs to be turned off
163
Q

Three Mechanisms by which enzymes within cell can be “turned on”

A
  1. feedback control associated with allosteric enzymes
  2. proteolytic enzymes and proenzymes/zymogens
  3. covalent modification
164
Q

occurs when a product of the reaction binds to an allosteric site on the enzyme and affects its catalytic activity

A

feedback control associated with allosteric enzymes

165
Q

enzymes that have an additional binding site for effector molecules other than the active site

A

Allosteric enzymes

166
Q

structure of Allosteric enzymes

A

quaternary structure

167
Q

two kinds of binding site of Allosteric enzymes

A
  • for substrate
  • for regulator
168
Q

binding sites of Allosteric enzymes

A

distinct from each other both in location and shape

169
Q

binding of molecule at regulatory site in Allosteric enzymes

A

changes in overall 3D structure including active site

170
Q
  • cell uses feedback inhibitiion to stop producing no longer needed product
  • effective metabolic on-off switch
A

feedback control

171
Q

product can shut off entire pathway for its synthesis

A

feedback control

172
Q

regulators or particular allosteric enyme may be what?

A
  1. products of entirely different pathways of reaction within cell
  2. compounds produced outside cell (hormones)
173
Q
  • synthesized as inactive precursors, or “zymogens,” to prevent unwanted protein degradation
  • enable spatial and temporal regulation of proteolytic activity
A

Proteolytic enzymes

174
Q
  • inactive form of proteolytic enzyme
  • converted by proteolysis to the active form when it reached site of its activity
A

proenzyme or zymogen

175
Q

hydrolysis of protein

A

proteolysis

176
Q

active form of enzyme

A

proteolytic enzymes

177
Q

example of proteolytic enzymes

A

most digestive and blood-clotting enzymes

178
Q

have amino acid serine in the catalytic region of active site that is essential for hydrolysis of peptide bond

A

serine protease

179
Q

process in which enzyme activity is altered by covalently modifying structure of enzyme through attachement of chemical group

A

covalent modification

180
Q

most common type of protein modification

A
  1. phosphorylation
  2. dephosphorylation
181
Q

QUICK QUIZ:
incorrect information about characterization of allosteric enzyme

A

substrate and regulator compete for same binding site

182
Q

QUICK QUIZ:
enzyme activity regulation that involves a reaction sequence product inhibiting an enzyme in an earlier step in the reaction sequence

A

feedback control

183
Q

QUICK QUIZ:
zymogen

A

inactive precursor of a proteolytic enzyme

184
Q
  • either eliminate or drastically reduce their catalytic ability
  • chemical that can bind to enzymes
A

enzyme inhibitors

185
Q

Ex. of enzyme inhibitors

A
  1. arsenic
  2. penicillin
186
Q
  • binds to thiol groups of cysteine amno acids in proteins
  • interfere with formation of disulfide bonds needed to stabilize tertiary structure of protein
A

arsenic

187
Q

inhibits several enzymes involved in synthesis of bacterial cell wall

A

penicillin

188
Q

Three modes of inhibition

A
  1. irreversible inhibition
  2. reversible competitive inhibition
  3. reversible noncompetitive inhibition
189
Q
  • generally do not have structures similar to that of enzyme’s normal substrate
  • bind very tightly, sometimes covalently, to enzyme
  • may interfere with catalytic groups of active site
  • generally inhibit many different enzymes
A

irreversible enzyme inhibitors

190
Q

ex. of irreversible enzyme inhibitors

A

sarin

191
Q
  • interferes with process by which nerve cells communicate
  • disrupts muscle movement and other processes the nervous system controls
A

sarin

192
Q

key factors whehter enzyme accepts molecule

A
  • molecular shape
  • charge distribution
193
Q
  • often refer to as structural analogs
  • molecules resemble structure and charge distribution of natural substrate
  • inhibitor can occupy enzyme active site
A

reversible competitive inhibitor

194
Q

reversible competitive inhibitor is often refer to as what

A

structural analogs

195
Q

Ex. of reversible competitive inhibitor

A

sulfa drug

196
Q
  • binds to active site of bacterial enzyme responsible for producing folic acid
  • folic acid production is stopped and bacterial cell will die
A

sulfa drug

197
Q

vitamin required for the making of DNA and RNA

A

folic acid

198
Q
  • molecule decreases enzyme activity by binding site on enzyme other than active site
  • substrate can still bind but presence of inhibitor causes change in structure of enzyme sufficient to prevent proper catalyzing action
  • increasing number of substrate do not completely overcome inhibitory effects
A

reversible noncompetitive inhibitors

199
Q

ex. of reversible noncompetitive inhibitors

A

heavy metal ions (Pb2+, Ag+, Hg2+)

200
Q
  • binding site for these ions are sulfhydryl groups (thiol) located away from active site
  • metal sulfide linkages are formed, disrupting secondary and tertiary structure
A

heavy metal ions (Pb2+, Ag+, Hg2+)

201
Q

PRACTICE:
inhibitor that decreases activity by binding to a site on enzyme other than active site

A

reversible noncompetitive inhibitor

202
Q

PRACTICE:
inhibitor that inactivates enzymes by forming strong covalent bond at enzyme active site

A

irreversible inhibitor

203
Q

QUICK QUIZ:
incorrect statement concerning reversible competitive inhibitor

A

binds at site other than active site

204
Q

QUICK QUIZ:
incorrect statement concerning irreversible enzyme inhibitor

A

has shape almost identical to that of normal substrate

205
Q

QUICK QUIZ:
binds to an enzyme at a location other than active site

A

reversible noncompetitive inhibitor

206
Q

PRACTICE:
Determine effect that each of the following changes would have on rate of biochemical reaction that involves substrate urea and liver enzyme urease

increasing urea concentration

A

enzyme activity will increase untill all enzyme molecules are engaged with urea substrate

207
Q

PRACTICE:
Determine effect that each of the following changes would have on rate of biochemical reaction that involves substrate urea and liver enzyme urease

increasing urease concentration

A

enzyme activity will increase untill all urea molecules are engaged with urease enzyme

208
Q

PRACTICE:
Determine effect that each of the following changes would have on rate of biochemical reaction that involves substrate urea and liver enzyme urease

increasing temperature from optimum value to 10C higher

A

enzyme activity will decrease

209
Q

PRACTICE:
Determine effect that each of the following changes would have on rate of biochemical reaction that involves substrate urea and liver enzyme urease

decreasing pH by one unit from optimum value

A

enzyme activity will decrease

z - CHM040 - Biomolecules (15 decks)

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