enzymes

Question 1

Enzyme associating inorganic ion (metals) to function

Answer 1

Cofactor

Question 2

Enzyme associating complex organic molecules like vitamins to function

Answer 2

Coenzyme

Question 3

Tightly associated cofactor or coenzyme

Answer 3

Prosthetic group

Question 4

belief that living things are fundamentally different
from non-living things because the contain some non-physical element
or are governed by different principles that inanimate objects.

Answer 4

Vitalism

Question 5

meaning “in yeast”, these are proteins that catalyze reactions

Answer 5

enzymes

Question 6

used to pre-digest proteins during manufacture of baby food, used together with lipase in bio detergents to break down stains

Answer 6

protease

Question 7

bio detergents to digest stains

Answer 7

lipase

Question 8

50% drug research on this type of enzyme, for treatment of cancer and such

Answer 8

kinase (inhibitors)

Question 9

protein portion of an anzyme, inactive by itself

Answer 9

apoenzyme

Question 10

apoenzyme+coenzyme/factor=

Answer 10

holoenzyme

Question 11

lower threshold energy needed for rxn to happen–>doesn’t change equilibrium, recycled

Answer 11

catalysts

Question 12

can catalyze 1 million substrate to product per second

Answer 12

carbonic anhydrase

Question 13

amost instantaneous conversion to product, highly stereospecific and doesn’t cause many side rxns/byproducts, function at physiological conditions, responsive to organism’s dynamic needs (allosteric regulation)

Answer 13

enzymatic catalysis

Question 14

often require extreme temp/pressure/pH, not as fast, specific or regulated reactions

Answer 14

chemical catalysis

Question 15

able to catalyze rxn faster by diffusion control limits–enzyme draws substrate towards itself to shorten rate determining step

Answer 15

Circe effect

Question 16

molecule acted on by enzyme

Answer 16

substrate

Question 17

what is produced by enzyme

Answer 17

product

Question 18

part of enzyme responsible for binding substrate to make enzyme substrate complex: 3D cleft, small, exclude water (unique microenviro), quite flexible (induced fit/comformation selection), bind substrate by weak noncovalent interactions

Answer 18

active site

Question 19

hand in glove: need specificity but also catalytic power

so substrate not exactly same as each other, enzyme select for subpopulation of substrate that is good

Answer 19

induced fit

Question 20

the
relationship between the rate of a
reaction and the activation energy is
___ and ____

Answer 20

inverse; exponential

Question 21

physical interactions between enzyme and substrate, including substrate binding and transition state stabilization–>enables substrate specificity and catalytic power

Answer 21

binding effects

Question 22

more obvious to see, involve acid/base catalysis, covalent catalysis; after substrate binding, enzyme act upon substrate to promote product form (polar ionizable a.a.)

Answer 22

chemical effects

Question 23

enzymes act as matchmakers, promote rxn by reduce entropy, strip away water, induce fit, distort substrate

Answer 23

substrate binding

Question 24

enzymes bind substrate much tighter in this state

Answer 24

transition state stabilization

Question 25

stable comps that resemble unstable transition states, bound to enzyme w/ higher affinity than natural substrate-->competitive inhibitors, used in drugs

Answer 25

transition state analogs

Question 26

antibodies generated against transition state analog

Answer 26

catalytic antibodies/abzymes

Question 27

reaction acceleration achieved by catalytic transfer of proton; often involve histidine

Answer 27

acid base catalysis

Question 28

two step process, first form covalent linkage with enzyme, second regenerate free enzyme

Answer 28

covalent catalysis

Question 29

study of rates at which rxns occur; initial reaction velocity vs. [S]

Answer 29

kinetics

Question 30

delta [P] / delta time

Answer 30

velocity (rate of reaction)

Question 31

rate of reaction in relationship to [E] is ___

Answer 31

linear relationship

Question 32

velocity at beginning of enzyme catalyzed reaction before product accumulation

Answer 32

initial velocity/pre-equilibrium velocity

Question 33

initial velocity = concentration of enzyme substrate complex x rate constant of formation of product from ES

Answer 33

Vo = [ES]k2

Question 34

what did Michaelis and Menton have to assume to derive their equation?

Answer 34

Steady state: rate of formation of ES = to rate of its breakdown

Question 35

what is the M-M equation?

Answer 35

Vo = Vmax [S] / Km + [S]

Question 36

the [S] required to reach half of Vmax

Answer 36

Km

Question 37

velocity becomes independent of substrate concentration at this point

Answer 37

Vmax

Question 38

if [S] is

Answer 38

enzymes are highly sensitive to changes in [S] but have very little activity

Question 39

if [S] is > Km then...

Answer 39

enzymes high activity but insensitive to [S] changes

Question 40

if [S] is = km then...

Answer 40

enzyme has significant activity and is responsive to [S] changes

Question 41

double reciprocal plot more precise than M-M, used to determine Vmax/Km: 1/Vo=Km/Vmax[S]+1/Vmax

Answer 41

Lineweaver-Burke

Question 42

the enzyme turnover number that looks at population of enzymes and takes average. Is # of cules of substrate converted to product per unit time under saturating conditions; calculated by Vmax/[Et]

Answer 42

kcat

Question 43

compound that binds to enzyme to infere w/ activity either prevent ES from form or prevent breakdown to E and P-->bind to enzyme by noncovalent interactions

Answer 43

reversible enzyme inhibition

Question 44

usually resembling the substrate, these inhibitors bind only to free enzyme and not ES. Vmax is same but apparent Km is ^

Answer 44

competitive inhibition

Question 45

bind only to ES, decreases Vmax and apparent Km (double reciprocal plot lines are parallel)

Answer 45

uncompetitive inhibition

Question 46

bind both E and ES, Vmax decreases with no change in Km

Answer 46

noncompetitive inhibition

Question 47

tend to be manmade, permanently inactivate enzyme, form highly stable interactions/covalent bonds with enzymes-->includes transition-state analogs

Answer 47

irreversible inhibitors

Question 48

specific type of irreversible enzyme inhibition, also called biochem trojan horses or mechanism based inactivators-->initially unreactive but converted to reactive species that inactivates enzyme (effective drugs)

Answer 48

suicidal inactivator

Question 49

digestive enzymes including trypsin, chymotrypsin, elastase that cleave peptide bonds in protein substrate; also function in mediating turnover of self proteins; synth and stored in pancreas as inactive zymogens

Answer 49

serine proteases

Question 50

stored in pancreas, inactive form of serine proteases, activated at proper time by selective proteolysis

Answer 50

zymogens

Question 51

serine protease that cleaves by Lys and Arg because it has deep pocket and negative charged end

Answer 51

trypsin

Question 52

serine protease that cleaves by Phe and Tyr | because it has a deep hydrophobic pocket

Answer 52

chymotrypsin

Question 53

serine protease that cuts all peptide bonds

Answer 53

papain

Question 54

serine protease that cuts by Gly and Ala because it has a shallow hydrophobic pocket

Answer 54

elastase

Question 55

serine proteases have a conserved catalytic mechanism based on Asp, His, and Ser. What is this referred to as?

Answer 55

Catalytic triad

Question 56

This residue removes H from Ser's OH to make it a strong nucleophile and activates a water cule to regenerate the free enzyme in acid base catalysis

Answer 56

Histidine

Question 57

This residue stabilizes the + charged His to facilitate serine ionization

Answer 57

Aspartate

Question 58

This residue acts as the nucleophile attacking the carbonyl group of polypeptide substrate in covalent catalysis-->usually in 2 steps: gen intermediate, then generate product

Answer 58

Serine

Question 59

how can you regulate the activity of enzymes over the long term?

Answer 59

by controlling enzyme availability: location, amounts, rates of synth/degrade

Question 60

how can you regulate the activity of an enzyme over the short term?

Answer 60

covalent (phosphorylation) and noncovalent modification (allosteric)

Question 61

this is important in aa with OH groups; posttranslational modifications; each protein has about 4 diff events of this, and about 16 diff permutations; critical for regulating function and activity

Answer 61

phosphorylation

Question 62

enzymatic pathways self-regulate, in response to bodily needs; shuts down first unique committed step in respects to branching points

Answer 62

negative feedback regulation

Question 63

interact w/ metabolic intermediates that bind noncovalently at sites distinct from active site, usually quaternary structure; often slow; sigmoidal curve, not follow M-M (cooperative activation)

Answer 63

allosteric enzymes

Question 64

below a certain substrate [] there is little enzyme activity; after threshold has been reached the enzyme activity ^ rapidly

Answer 64

threshold effect

Question 65

What is PFK1?

Answer 65

catalyzer of early step in glycolysis

Question 66

What is the allosteric inhibitor of PFK1?

Answer 66

PEP

Question 67

what is an allosteric activator of PFK1?

Answer 67

ADP

Question 68

Phosphoryl groups are added by ____ and removed by _____

Answer 68

kinases; phosphatases

Question 69

production of glycogen from glucose is catalyzed by ___ and broken down into glucose by ____

Answer 69

glycogen synthase' glycogen phosphorylase

Question 70

which hormones in a hungry state cause phosphorylation, which activates catabolic enzymes and inactivates anabolic enzymes, breaking glycogen into glucose?

Answer 70

glucagon and epinephrine

Question 71

which hormone in a fed state cause both enzymes to be unphosphorylated, which activates anabolic enzyme and inactivates catabolic E, storing glucose as glycogen?

Answer 71

insulin