Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biochemistry > Module 04: Enzymes (Comprehensive) > Flashcards

Module 04: Enzymes (Comprehensive) Flashcards

1
Q

These are specialized proteins with catalytic properties

A

Enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

This specificity pertains to stereoisomer

A

stereochemical specificity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

This specificity pertains to substrate it will act upon

A

absolute specificity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

This specificity pertains to the type of bond/linkage

A

linkage specificity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Chemical reactions need an initial input of energy to reach this.

A

Activation Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

During the activation energy, the molecules are said to be in what?

A

Transition state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

This provides an alternate route, one with lower energy of activation and it stabilizes the transition state

A

Enzyme Controlled Pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the structure of the active site.

A

Cleft or pocket on the enzyme’s surface, With catalytic and binding sites, where catalysis occurs (at catalytic residues)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is the active site located?

A

Located at the interface between subunits of multimeric enzymes (Shields the substrate from solvent)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

An additional non-protein molecule that is needed by some enzymes to help the reaction. These are small organic or metalloorganic molecules or metal ions.

A

Cofactor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Tightly bound cofactors are called _______________..

A

prosthetic groups (heme in hemoglobin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Organic cofactors that are bound and released easily are called ____________ and are commonly activated by vitamins.

A

coenzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

These can associate and disassociate from enzymes between reactions cycles thus behaving like substrates.

A

Weakly bound coenzymes (cosubstrates)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

This is the protein part of an enzyme that is inactive. It requires a cofactor to be active.

A

Apoenzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

This is the complete catalytically active enzyme

A

Holoenzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

This is the enzymes requiring metal ions as cofactor

A

Metalloenzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

These function as group transfer agents, Transport substrates from port of generation to port of utilization. They are usually derived from vitamins.

A

Coenzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

These coenzymes transfer H atoms or Hydrides

A

NAD+ (Nicotinic acid/niacin/B3 )

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

These coenzymes transfer methyl group.

A

folates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

These coenzymes transfer acyl group.

A

Pantothenic acid/B5 (Coenzyme A)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

These coenzymes transfer oligosaccharides.

A

dolichol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

These coenzymes transfer Electrons .

A

Riboflavin/B2 (FAD and FMN)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

These coenzymes transfer aldehyde group transfer.

A

Thiamine/B1 (thiamin pyrophosphate/TPP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

These coenzymes transfer Activated CO2 group transfer

A

Biocytin (Biotin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
These coenzymes transfer One C group transfer
Folic acid (Tetrahydrofolate/THF)
25
These coenzymes transfer H and alkyl groups Electrons & acyl groups
(1) Deoxyadenosyl cobalamin (B12) (2) Lipoic acid (lipoate) is not required in the diet
26
These are the reactants that are acted upon/activated by the enzyme
substrates
27
The specificity is determined by the "________________"
active site
28
In this theory of specificity, the fit between the substrate and the active site of the enzyme is exact Like a key fits into a lock very precisely. The key is analogous to the substrate and the enzyme analogous to the lock
The Lock and Key Hypothesis
29
What is the temporary structure of the lock and key hypothesis?
Temporary structure called the enzyme-substrate complex /ES complex formed
30
What happens when the enzyme-substrate is formed/
Once formed, they are released from the active site leaving it free to become attached to another substrate
31
Dehydrogenase, oxidase are examples of what
Oxidoreductase enzymes
32
Kinase, amino transferase are examples of what
Transferase
33
Esterase, glycosidase, peptidase, phosphatase, phospholipase are examples of what?
Hydrolase
34
Decarboxylase, synthase are examples of what
Lyase
35
Epimerase, mutase are examples of what
Isomerase
36
Synthetase, carboxylase are examples of what
Ligase
37
The substrate concentration in non-enzymatic reactions is directly proportional to what
The increase in velocity is proportional to the substrate concentration (Faster reaction but it reaches a saturation point when all the enzyme molecules are occupied)
38
Faster reaction but it reaches a saturation point when all the enzyme molecules are occupied, this stage is called the
Vmax
39
What happens when you alter the concentration
If you alter the concentration of the enzyme then Vmax will change too.
40
What happens when there is Extreme pH levels
Extreme pH levels will produce denaturation (The active site is distorted and the substrate molecules will no longer fit in it)
41
These changes affects binding of the substrate with the active site.
small changes in the charges of the enzyme and its substrate molecules will occur ( change in ionization)
42
What is the temperature coefficient?
Q10 (the temperature coefficient) - the increase in reaction rate for every 10°C rise in temperature.
43
What does the Q10 = 2 to 3 mean?
(the rate of the reaction doubles or triples with every 10°C rise in temperature)
44
BUT at high temperatures (beyond the optimum) proteins denature at around _______
70°C
45
In terms of enzyme concentration, the increase in velocity is proportional to what?
The increase in velocity is proportional to the enzyme concentration
46
What are the uses of the double reciprocal plot?
(1) The biggest advantage to using the double reciprocal plot is a more accurate determination of VMax, and hence KM. (2) The x intercept value is equal to -1/KM. (3) It is also useful in characterizing the effects of enzyme inhibitors and distinguishing between different enzyme mechanisms.
47
What are the different types of irreversible inhibition?
(1) group specific covalent modifying agents (2) Affinity labels (3) Transition state analogs (4) Suicide inhibitors
48
These react with specific type of functional group or any enzyme protein.
group specific covalent modifying agents
49
These are enzymes in nucleotide biosynthesis (new nucleic acids required for cell division)
dihydrofolate reductase
50
This inhibits vertebrae DHRF and selectively kills rapidly dividing cells.
Methotrexate
51
This inhibits prokaryotic DHFR.
Trimethoprim
52
This pertains as to how Eukaryotic cells are divided into organelles which often allows for separation of opposing processes.
Compartmentation
53
Fatty acid oxidation occurs in the
mitochondria
54
synthesis occurs in the .
cytosol
55
These are different forms of an enzyme found in different organelles or different tissues but Catalyze the same reaction
Isozymes
56
A tetramer whose subunits occur in two forms (H for heart) and (M for muscle)
Isozymes of Lactate DH(LDH)
57
How do Isozymes differ?
(1) Substrate affinity (glucokinase and hexokinase) (2) Sensitivity to regulatory factors
58
This isozymes predominates in the heart
I1 or H4
59
This isozymes predominates in the liver
I5 or M4
60
Elevation in I1 or I5 is detected by
separating oligomers of LDH by electrophoresis
61
Dimeric CK has two types of protomers:
muscle (M) and brain (B).
62
Heart muscle has
CK2 (MB) and CK3 (MM).
63
This is found exclusively in heart muscle.
CK2
64
When is CK2 released?
CK2 is released 6 hrs. after chest pain and reaches a maximum after 18 hrs.
65
These are enzymes tested for the diagnosis of MI
Troponin, lactate dehydrogenase and creatine kinase
66
This is the more definitive diagnostic test because it is more cardiac specific than the others
Troponin

Biochemistry (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions