Enzyme

Question 1

proteins that are catalysts of biochemical reactions.

Answer 1

Enzymes

Question 2

not consumed during a
chemical reaction.

Answer 2

Catalyst

Question 3

Typically has a
globular shape. It has a complex 3-D structure.

Answer 3

Enzymes

Question 4

First clear recognition of enzyme was made by ?

Answer 4

Payen and Persoz (around 1833)

Question 5

an alcohol precipitate of malt extract contained in a thermolabile substance that converted starch to sugar.

Answer 5

Diastase

Question 6

use of -ase in naming enzyme

Answer 6

Duclaux (1898)

Question 7

first to crystallize enzyme (urease)

Answer 7

J.B. Sumner (1924-1930)

Question 8

modulates an enzyme activity

Answer 8

Effectors

Question 9

found in animal and plant cells

Answer 9

Catalase

Question 10

found in saliva and in the pancreas. It breaks down starch down to
maltose.

Answer 10

Amylase

Question 11

synthesize enzyme (builds up). It builds/combines multiple
Glucose-1-Phosphate molecules into starch

Answer 11

Potato Phosphorylase

Question 12

characteristic of catalyst. High efficiency, 10^3 to 10^17 faster
than the corresponding uncatalyzed reactions.

Answer 12

Catalytic efficiency

Question 13

a characteristic of catalyst. High _________, interacting with one
or a few specific substances and catalyzing only one type of chemical reaction.

Answer 13

Specificity

Question 14

characteristic of catalyst, 37℃, physiological pH, ambient atmospheric pressure.

Answer 14

Mild reactions conditions

Question 15

a part of the enzyme where the reactants bind, where the biochemical reaction occurs.

Answer 15

Active Site

Question 16

The enzyme active site is usually composed of?

Answer 16

amino acid side chains interact,
metal ions, various types of polar, non-polar, ionic interactions.

Question 17

a region within an enzyme that fits the shape of molecules called substrates or reactants.

Answer 17

Active Site

Question 18

The active site contains…

Answer 18

amino acid R groups that align and bind the substrate.

Question 19

The substrates fit like a key in a lock and the active site is the lock itself. If the conditions are satisfied, a chemical reaction will occur to form products. After the reaction, the enzyme is unchanged.

Answer 19

“Lock and Key Model”

Question 20

additional non-protein molecule that is needed by some enzymes to help the reaction

Answer 20

Cofactors

Question 21

Cofactors that are bound and released easily are called

Answer 21

Coenzymes

Question 22

present in trace amounts within the enzyme.

Answer 22

Metal Ions

Question 23

a cofactor for carboxypeptidase

Answer 23

Zn^2+

Question 24

non-protein or organic, maybe a vitamin

Answer 24

Coenzyme

Question 25

catalyze the same reaction in different tissues in the body

Answer 25

Isoenzymes

Question 26

which converts lactate to pyruvate consists of five isoenzymes.

Answer 26

Lactate dehydrogenase

Question 27

first created the classifications in enzyme system

Answer 27

IUPAC (International Union for Pure and Applied Chemistry)

Question 28

developed the four-integer number system and a name.

Answer 28

EC or the Enzyme Commission

Question 29

Enzymes are classified according to the type of reaction they catalyze: a. Oxidoreductases

Answer 29

oxidation-reduction reactions.

Question 30

Enzymes are classified according to the type of reaction they catalyze: b. Transferases

Answer 30

transport/transfer of group of atoms or single atoms

Question 31

Enzymes are classified according to the type of reaction they catalyze: c. Hydrolases

Answer 31

Hydrolysis

Question 32

Enzymes are classified according to the type of reaction they catalyze: d. Lyases

Answer 32

adding or removing atoms to form a double bond.

Question 33

Enzymes are classified according to the type of reaction they catalyze: e. Isomerases

Answer 33

rearranging atoms

Question 34

Enzymes are classified according to the type of reaction they catalyze: f. Ligases

Answer 34

using ATP to combine molecules (substrates).

Question 35

EC first integer:

Answer 35

six major classes of enzyme catalyzed reactions.

Question 36

Second integer:

Answer 36

a subclass

Question 37

Third integer:

Answer 37

sub classification depending on 1st and 2nd integer.

Question 38

Fourth integer:

Answer 38

serial number

Question 39

rate of reaction between two molecules is enhanced if they are abstracted from dilute solution and held in close proximity to each other

Answer 39

Facilitation of Proximity

Question 40

This mechanism involves the transient covalent bonding of the substrate to an amino acid residue in the active site.

Answer 40

Covalent Catalysis

Question 41

more prone to undergoing covalent catalysis reactions

Answer 41

nucleophilic groups

Question 42

many reactions involve the formation of normally unstable, charge intermediates.

Answer 42

General Acid-Base Catalysis

Question 43

accounts for the overall lowering of activation energy for a reaction, and it can also be considered as a catalytic mechanism for a reaction.

Answer 43

Binding Energy

Question 44

– various metals, all positively charged including zinc, iron, magnesium, manganese, and copper are known to form complexes with different enzymes or substrates.

Answer 44

Metal Ion Catalysis

Question 45

The binding of the substrate results in the distortion of the substrate in a way that makes the chemical reaction easier

Answer 45

Strain, Molecular Distortion, and Shape Change

Question 46

Common enzymes used for clinical diagnosis

Answer 46

alanine aminotransferase (ALT, also called glutamate pyruvate transaminase GPT), alkaline phosphatase, amylase, aspartate aminotransferase, creatine kinase, and lactate dehydrogenase.

Question 47

the reaction is in between the reactant consumption and product formation (peak).

Answer 47

Transition State

Question 48

Increasing the temperature make molecules

Answer 48

move faster

Question 49

very sensitive to temperature changes

Answer 49

Biological systems

Question 50

Enzymes can increase the rate of reactions without?

Answer 50

increasing/requiring an increase in the temperature.

Question 51

they catalyze one type of reaction for a single substrate.

Answer 51

Absolute Enzymes

Question 52

they catalyze one type of reaction for similar substrates

Answer 52

group enzymes

Question 53

they catalyze one type of reaction for a specific type of bond.

Answer 53

linkage enzymes

Question 54

The lock and key hypothesis

Answer 54

1. Temporary structure called the enzyme-substrate complex formed. 2. Products have a different shape from the substrate. 3. Once formed, they are released from the active site. 4. Leaving it free to become attached to another substrate.

Question 55

Induced fit theory

Answer 55

1. Enzyme changes shape with substrate. 2. The active site is not rigid. 3. The active site is capable of changing its shape depending upon the substrate.

Question 56

the active site is flexible, not rigid, the shapes of the enzyme, active site, and substrate adjust to maximum the fit which improves the catalysis, and there is a greater range of substrate specificity

Answer 56

induced fit model of enzyme action

Question 57

The induced fit hypothesis:

Answer 57

1. Some proteins can change their shape (conformation). 2. When a substrate combines with an enzyme, it induces a change in the enzyme’s conformation. 3. The active site is then molded into a precise conformation. 4. Making the chemical environment suitable for the reaction. 5. The bonds of the substrate are stretched to make the reaction easier (lowers activation energy).

Question 58

When a substrate (S) fits properly in an active site, what is formed?

Answer 58

an enzyme-substrate complex (ES) 𝐸 + 𝑆 → 𝐸𝑆 (𝑟𝑒𝑣𝑒𝑟𝑠𝑖𝑏𝑙𝑒)

Question 59

Within the active site of the ES complex, what happened?

Answer 59

the reaction occurs to convert substrate to product (P): 𝐸𝑆 → 𝐸 + 𝑃 (𝑖𝑟𝑟𝑒𝑣𝑒𝑟𝑠𝑖𝑏𝑙𝑒)

Question 60

The overall reaction for the conversion of substrate

Answer 60

𝐸 + 𝑆 → 𝐸𝑆(𝑟𝑒𝑣𝑒𝑟𝑠𝑖𝑏𝑙𝑒) → 𝐸 + 𝑃 (𝑖𝑟𝑟𝑒𝑣𝑒𝑟𝑠𝑖𝑏𝑙𝑒)

Question 61

Enzymatic reaction steps

Answer 61

1. Substrate approaches the active site 2. Enzyme-substrate complex forms 3. Substrate transformed into products 4. Products released 5. Enzyme recycled (depends on the enzyme, not always)

Question 62

The reaction for the sucrase catalyzed hydrolysis of sucrose to glucose and fructose.

Answer 62

𝑆𝑢𝑐𝑟𝑎𝑠𝑒 + 𝑆𝑢𝑐𝑟𝑜𝑠𝑒 → 𝐸𝑆 𝑐𝑜𝑚𝑝𝑙𝑒𝑥 (𝑟𝑒𝑣𝑒𝑟𝑠𝑖𝑏𝑙𝑒) → 𝑆𝑢𝑐𝑟𝑎𝑠𝑒 + 𝐺𝑙𝑢𝑐𝑜𝑠𝑒 + 𝐹𝑟𝑢𝑐𝑡𝑜𝑠𝑒 (𝑖𝑟𝑟𝑒𝑣𝑒𝑟𝑠𝑖𝑏𝑙𝑒)