L3 Coenzymes

Question 1

Coenzymes contain catalytic amino acid residues, true or false?

Answer 1

False. The enzyme contains catalytic amino acid residues instead of coenzymes

Question 2

Does coenzymes undergo chemical changes during an enzyme-catalyzed reaction?

Answer 2

Yes

Question 3

Coenzymes may be attached tightly to an enzyme, true or false?

Answer 3

False

Question 4

Essential ions can be divided into which two categories?

Answer 4

Activator ions and metal ions of metalloenzymes

Question 5

Cofactors can be divided into which two categories?

Answer 5

Essential ions and coenzymes

Question 6

Coenzymes can be divided into which two categories?

Answer 6

Cosubstrates and prosthetic groups

Question 7

What does apoenzyme mean?

Answer 7

Enzyme without cofactor

Question 8

What does holoenzyme mean?

Answer 8

enzyme with cofactor

Question 9

Which one is chemically altered after the reaction instead of during the reaction, cosubstrates or prosthetic groups?

Answer 9

Cosubstrates

Question 10

Which one is regenerated to original state after the reaction instead of regenerated in a subsequent reaction, cosubstrates or prosthetic groups?

Answer 10

Prosthetic groups

Question 11

What is the function of S-Adenosylmethionine (SAM)?

Answer 11

Transferring a methyl group

Question 12

Is SAM a cosubstrate or prosthetic group

Answer 12

Cosubstrate

Question 13

What is the function of nucleotide sugar phosphates (UDP)?

Answer 13

Transferring a glucose unit

Question 14

Give an example of UDP glucose acting as the cosubstrate.

Answer 14

In glycogen synthase, it transfers glucose 1-phosphate to UDP glucose

Question 15

Is SAM a cosubstrate or prosthetic group

Answer 15

Cosubstrate

Question 16

Vitamin B1 derives into what coenzyme?

Answer 16

Thiamine diphosphate (TDP)

Question 17

Is TDP a prosthetic group or cosubstrate?

Answer 17

Prosthetic group

Question 18

What is the function of TDP?

Answer 18

Carboxyl group transfer

Question 19

Vitamin B2 derives into what coenzyme?

Answer 19

FAD/FMN

Question 20

Is FAD/FMN a prosthetic group or cosubstrate?

Answer 20

Prosthetic group

Question 21

What is the function of FAD/FMN?

Answer 21

Oxidation-reaction

Question 22

Is NAD+/NADP+ a prosthetic group or cosubstrate?

Answer 22

Cosubstrate

Question 23

Vitamin B3 derives into what coenzyme?

Answer 23

NAD+/NADP+

Question 24

What is the function of NAD+/NADP+?

Answer 24

Oxidation-reaction

Question 25

Vitamin B5 derives into what coenzyme?

Answer 25

Acetyl-CoA

Question 26

What is the function of Acetyl-CoA

Answer 26

Acyl group transfer

Question 27

Which group in CoA is responsible for the attachment of acyl group?

Answer 27

Thiol (-SH) group

Question 28

Vitamin B6 derives into what coenzyme?

Answer 28

Pyridoxal 5’-phosphate (PLP)

Question 29

Is Pyridoxal 5’-phosphate (PLP) a prosthetic group or cosubstrate?

Answer 29

Prosthetic group

Question 30

What is the function of Pyridoxal 5’-phosphate (PLP) ?

Answer 30

Amino group transfer

Question 31

Vitamin B7 (aka biotin) covalently linked to which AA residue in enzyme active site?

Answer 31

Lysine

Question 32

Is biotin a prosthetic group or cosubstrate?

Answer 32

Prosthetic

Question 33

What is the function of biotin?

Answer 33

Carboxyl group transfer

Question 34

Vitamin B9 derives into what coenzyme?

Answer 34

Tetrahydrofolate (THF)

Question 35

Is Tetrahydrofolate (THF) a prosthetic group or cosubstrate?

Answer 35

Cosubstrate

Question 36

What is the function of THF?

Answer 36

Transferring of 1-carbon units (e.g. methyl group, methylene group, formyl group)

Question 37

What is the characteristic structure of vitamin B12?

Answer 37

Corrin ring with cobalt cation

Question 38

Is B12 a prosthetic group or cosubstrate?

Answer 38

Prothetics group

Question 39

What is the function of vitamin B12?

Answer 39

Methyl group transfer or intramolecular rearrangements