Vitamins and Cofactors

Question 1

Oxygenase and dehydrogenase are a ______ class of enzyme. Kinases, acyltransferase, and acetyltransferase are all _____ class of enzymes.

Answer 1

Oxidoreductase
Transferase

Question 2

_____ reactions function in the body for fuel oxidation, detoxification, and biosynthesis

Answer 2

Redox

Question 3

Redox cofactors include _____, ____ , ____, ____, ______

Answer 3

NADH, NADPH, FAD(2H), ascorbic acid, and metals such as copper, iron.

Question 4

What is this cofactor:

Answer 4

Nicotinamide adenine dinucleotide (NAD+) . The pink hydrogen at the top shows the active side and where the reduction takes place to for NADH

Question 5

An example of a redox reaction is lactate to pyruvate, where ____ is the cofactor.

Answer 5

NAD+

Question 6

A reaction usually uses only ____ or ___, not both. ____ is primarily used in fuel oxidation. ____ is used in detoxification and biosynthesis.

Answer 6

NADH or NADPH
NADH
NADPH

Question 7

The dietary precursor for NADH and NADPH is ______. It is abundant in meat, whole grains, and fortified cereals.

Answer 7

Niacin (vitamin B3)

Question 8

Niacin can by synthesized in the body from _____, which we also get from our diet. This requires vitamin ____.

Answer 8

Tryptophan
Vitamin B6

Question 9

Deficiency of niacin causes ______, characterized by dermatitis, diarrhea, and dementia (3Ds).

Answer 9

Pellagra

Question 10

____ and ____ are also redox cofactors but they accept 1 electron at a time. They also participate in creating and breaking ____ bonds and ____ bonds.

Answer 10

FMN and FAD
Double
Disulfide

Question 11

FMN stands for ____ ____. FAD stands for _____ ____ ____. They are similar but FAD has an added adenosine that acts as a _____ where enzymes grab on to.

Answer 11

Flavin mononucleotide
Flavin adenine dinucleotide
Handle

Question 12

FAD and FMN are derived from ______.

Answer 12

Riboflavin (vitamin B2)

Question 13

Succinate dehydrogenase uses ______ as a redox cofactor.

Answer 13

FAD

Question 14

Riboflavin (vitamin B2) comes from ___, ____, _____, ____, and _____ in our diet

Answer 14

Milk, eggs, organ meat, legumes, and mushrooms

Question 15

Riboflavin is phosphorylated by ______ using ATP to create ______. Then an adenine is added by enzyme _____ to form FAD.

Answer 15

Flavokinase
FMN
FAD synthetase

Question 16

Riboflavin deficiency results in _____ and ____, which are sores around the mouth and a beefy swollen tongue, respectively. Anemia, dermatitis, GI malabsorption, or mutations in succinate dehydrogenase can also occur.

Answer 16

Cheilosis
Glossitis

Question 17

______ is a redox cofactor for hydroxylase enzymes important in collagen synthesis, neurotransmitter synthesis, and oxygen sensing. It also functions as a ______ anti-oxidant

Answer 17

Ascorbic acid (vitamin C)
Non-enzymatic

Question 18

Hydroxylase enzymes add and ___ group which allows for hydrogen bonding in collagen. If ____ is deficient, hydroxylase is unable to function properly leading to weak collagen.

Answer 18

OH
Ascorbic acid (vitamin C)

Question 19

Vitamin C (ascorbate) is a cofactor for ____ hydroxylase. Post translational hydroxylase of ____ and ____ is important for collagen formation.

Answer 19

Prolyl
Lysine
Proline

Question 20

____ hydroxylase adds a OH group to lysine

Answer 20

Lysyl

Question 21

Collagen is important for extracellular connective tissue. In the collagen peptide, every third amino acid is ____. Collagen peptides form a ___ ___ structure that is stabilized by hydrogen bonding.

Answer 21

Glycine
Triple helix

Question 22

Ascorbic acid (vitamin C) is found in ____ and ____ in our diet.

Answer 22

Citrus
Vegetables

Question 23

____ is an ascorbic acid deficiency characterized by defects in connective tissue, bleeding, slow wound healing, anemia, gingival lesions (gum lesion), enlargement of costochondral junctions, and Pertichia (bleeding capillaries)

Answer 23

Scurvy

Question 24

Diagnose scurvy by clinical presentation, _____ findings, and _____ clearance after oral ascorbate bolus.

Answer 24

Radiologic
Urinary

Question 25

_____ is important for iron absorption.

Answer 25

Ascorbic acid (vitamin C)

Question 26

_____ ____ is an activation transfer cofactor. It participates in decarboxylation reactions. After decarboxylation of pyruvate the remaining two carbons form a ____ bond with TPP.

Answer 26

Thiamine pyrophosphate (TPP) Covalent

Question 27

Thiamine is found in ____, _____, _____, and _____ in our diet.

Answer 27

Meat, legumes, whole grains, fortified cereals

Question 28

Thiamine deficiency can occur in _____ and _____. _____ is characterized by headache, nausea, malaise, heart failure. _____ _____ is characterized by confusion and abnormal eye movements. ____ ____ is characterized by amnesia and confabulation.

Answer 28

Malnutrition Alcoholism Beriberi Wernicke encephalopathy Koraskoff psychosis

Question 29

____ ____ ____ ____ syndrome is due to inherited mutations in the thiamine transporter SLC19A2. Characterized by anemia, progressive deafness, and non type I diabetes

Answer 29

Thiamine responsive megaloblastic anemia

Question 30

_____ is an activation transfer cofactor that forms a covalent bond with lysine side chains.

Answer 30

Lipoate

Question 31

Lipoate is a cofactor for the E2 subunit of _____ _____. It accepts the two carbon acetate from TPP. Lipoate has ____ transfer function and ______ function

Answer 31

Pyruvate dehydrogenase Carbon Oxidation reduction

Question 32

_____ does not require a vitamin precursor. _____ and _____ synthesis lipoid acid. Deficiency is not fully described

Answer 32

Lipoate Fatty acids Amino acids

Question 33

_____ is an activation transfer cofactor. It functions to covalently bind _____ groups through high energy thioester bonds, and transfer them to different substrates

Answer 33

Coenzyme A (CoASH or CoA) Acyl

Question 34

The dietary precursor for coenzymeA is _______. It is widespread in the diet and specific deficiency is not described

Answer 34

Pantothenic acid (vitamin B5)

Question 35

____ is a activation transfer coenzyme. It is a cofactor for four carboxylase enzymes.

Answer 35

Biotin

Question 36

_____ reactions are the formation of new carbon-carbon bonds from inorganic carbon

Answer 36

Carboxylation

Question 37

_____ is widely distributed in food and deficiencies are rare. Raw eggs contain _____ which binds to biotin and makes in indigestible. Symptoms include scaley dermatitis, thinning hair, and alopecia

Answer 37

Biotin Avidin

Question 38

____ ____ is an activation transfer cofactor for enzymes that metabolize amino acids.

Answer 38

Pyridoxal phosphate (PLP)

Question 39

____ is a type of enzyme that uses PLP as a cofactor to metabolize amino acids

Answer 39

Transaminases

Question 40

_____ is the precursor for pyridoxal phosphate.

Answer 40

Vitamin B6

Question 41

3 types of vitamin B6 are ___ , ___, ____. They are found in the diet in meat, bananas, rice. They must be _____ by kinase to convert them to _____.

Answer 41

Pyridoxine Pyridoxal Pyridoxamine Pyridoxal phosphate

Question 42

Pyridoxal deficiency is characterized by ____, ____, and anemia in infants and _____ ____ in adults.

Answer 42

Seizures, diarrhea Peripheral neuropathy

Question 43

PLP is a cofactor in the pathway that converts tryptophan to ____. PLP deficiency can cause a ____ deficiency.

Answer 43

Niacin Niacin

Question 44

Direct measurement of ___ in blood is a diagnostic tool to measure PLP deficiency.

Answer 44

PLP

Question 45

PLP overdose causes _____ and ____.

Answer 45

Sensory neuropathy and ataxia

Question 46

_____ is an activation transfer cofactor that participates in transfers and rearrangements of methyl groups

Answer 46

Cobalamin (vitamin B12)

Question 47

The two forms of cobalamin in the body are ____ and ____.

Answer 47

Deoxyadenosylcobalamin Methylcobalamin

Question 48

Methylcobalamin is a cofactor for ______ synthase. After transferring its ____ group, Methylcobalamin is regenerated by accepting a ____ group from methyltetrahydrofolate. Methionine is important for protein synthesis.

Answer 48

Methionine Methyl Methyl

Question 49

Adenosylcobalamin is a cofactor for ______ _____ _____, which is essential for the catabolism of branched chain amino acids and fatty acids

Answer 49

Methylmalonyl CoA mutase

Question 50

____ is only produced by bacteria, it is found in meat, milk, and other animal derived foods. Deficiency can occur in vegans and causes _____, ____, ____, ____, and _____.

Answer 50

Cobalamin Anemia, weakness, fatigue, seizures, and sensory defects

Question 51

Diagnosis of cobalamin deficiency by ___ ___ and testing the cobalamin concentration in serum.

Answer 51

Blood smear

Question 52

What vitamin derived cofactors are required for different aspects of fuel oxidation?

Answer 52

Question 53

Which type of enzyme uses biotin as a cofactor?

Answer 53

Carboxylase

Question 54

Answer 54

Carboxylase

Question 55

Answer 55

White cell acetyl CoA carboxylase assay

Question 56

Answer 56

Lack of dietary vitamin B12

Question 57

Answer 57

Cyanocobalamin (Vitamin B12)

Question 58

Answer 58

Methionine cycle