002 Enzymes and Isozymes

Question 1

mass action (Le Chatelier’s principle)

Answer 1

increase the concentration of the reactants

decrease the concentration of the products

Question 2

coupling reactions is possible if they share a

Answer 2

common intermediate

Question 3

thermodynamics (delta G) is whether the reaction will proceed without

Answer 3

the input of energy (not indicative of velocity)

Question 4

reaction velocity (v) is increased by

Answer 4

a catalyst (an enzyme)

Question 5

what you can release in urine to change the pH and start metabolic acidosis

Answer 5

bicarbonate (will lower pH)

Question 6

diabetic acidosis

Answer 6

when you breakdown ketone bodies, they release a proton that will put the body into a acidotic condition, they cannot absorb glucose from the blood

Question 7

two types of biochemical rxns

Answer 7

oxidation reduction rxns

acid/base rxns

Question 8

all types of biochemical reactions are this type of rxn

Answer 8

transfer rxn

Question 9

normal blood pH

Answer 9

7.37-7.43

Question 10

bicarbonate dissociation equation

Answer 10

H+ and HCO3- H2CO3 (carbonic anhydrase) CO2 + H20)

Question 11

Respiratory acidosis (blood pH < 7.37)

Answer 11

hypoventilation leads to increased CO2 in blood so reaction is shifted to left and more protons produced which lowers pH

Question 12

metabolic acidosis (blood pH < 7.37) caused by either

Answer 12

addition of strong acid (lactate, ketone bodies)

loss of HC03- (diarrhea or weak kidneys)

Question 13

respiratory alkalosis (blood pH > 7.43)

Answer 13

hyperventilation leads to a decrease of CO2 in blood so reaction shifts to the right which lowers proton concentration and raises pH

Question 14

metabolic acidosis (blood pH > 7.43) caused by either

Answer 14

addition of a strong base (ingestion of acid)

loss of acid (vomiting)

Question 15

the conjugate acid of the bicarbonate base (HCO3-) is

Answer 15

carbonic acid (H2CO3)

Question 16

the conjugate acid of the ammonia base (NH3)

Answer 16

ammonium ion (NH4+)

Question 17

the conjugate base of acetoacetic acid is

Answer 17

acetoacetate

Question 18

the conjugate base of hydroxybutyric acid is

Answer 18

hydroxybutyrate

Question 19

six classes of enzymes

Answer 19

1. oxidoreductases
2. transferases
3. isomerases
4. lyases (synthases)
5. ligases (synthetases)
6. hydrolases

Question 20

oxidoreductases

Answer 20

transfer electrons from a donor (reducing agent) to an acceptor (oxidizing agent)

Question 21

transferases

Answer 21

transfer a functional group (amino, phosphate) between molecules

Question 22

isomerases

Answer 22

rearrange/isomerize molecules

Question 23

lyases (synthases)

Answer 23

add or remove atoms (elements of water, ammonia, CO2) to or from a double bond

Question 24

ligases (synthetases)

Answer 24

form (C-O, C-S,C-N, or C-C) bonds with the hydrolysis of ATP

Question 25

hydrolases

Answer 25

cleave bonds via the addition of water

Question 26

metalloenzymes

Answer 26

``` Cu Fe Mg (associated with phosphates) Se Zn ```

Question 27

proenzymes

Answer 27

enzymes that are inactive that get activated by a zymogen (e.g. pepsinogen)

Question 28

catalytic triad

Answer 28

converts serine 195 into a potent nucleophile

Question 29

what type of Vmax and Km are fast enzymes

Answer 29

a high Vmax and a low Km

Question 30

competitive inhibitors

Answer 30

makes the substrate unable to bind to enzyme Vmax stays the same, Km increased increasing [S] deters this

Question 31

noncompetitive inhibition

Answer 31

the inhibitor binds to free and substrate bound enzymes Vmax lowered, Km stays the same increasing [S] will not change anything (the reason Vmax is lowered is because you are reducing the active enzyme concentration)

Question 32

uncompetitive inhibition

Answer 32

inhibitor binds only to enzyme-substrate complex | Vmax lowered and Km lowered

Question 33

enzyme inactivation

Answer 33

irreversible inactivators Vmax lowered and Km unchanged increasing [S] will not allow the substrate to outcompete inhibitor

Question 34

allosteric enzymes

Answer 34

can have positive or negative effects on the binding of the enzyme. they bind to a site other than the active site which then alters the active site

Question 35

isoenzymes

Answer 35

proteins that resemble one another from different genes but basically the same protein. important in diagnosing the tissues/organs of your patient

Question 36

Cu activity

Answer 36

``` cytochrome c oxidase ferroxidase superoxide dismutase (antioxidant) lysyl oxidase tyrosinase ```

Question 37

Fe activity

Answer 37

Heme proteins cytochromes catalases and peroxidases

Question 38

Mg

Answer 38

ATPases adenylate cyclase kinases

Question 39

Se

Answer 39

glutathione peroxidase

Question 40

Zn

Answer 40

``` superoxide dismutase (antioxidant) collagenase alcohol dehydrogenase alkaline phosphatase transcription factors carbonic anhydrase ```