Enzymes - Davies

Question 1

Cofactors

Answer 1

small inorganic attachments to enzymes

Question 2

Coenzymes

Answer 2

Organic Molecules that attach to enzymes.

Question 3

Metalloprotease

Answer 3

Require metal ion to cleave proteins (uses Zn)

Question 4

Kinase

Answer 4

Uses Mg to work and is calcium concentration depended. it wil lphosphorylate

Question 5

Oxidoreductase

Answer 5

oxidate and reduction reaction

Question 6

Transferase

Answer 6

transfer functional group

Question 7

Hydrolase

Answer 7

catalyze bond cleavage with water

Question 8

lyases

Answer 8

c-c bond cleavage

Question 9

isomerase

Answer 9

move a group or a double bond

Question 10

ligases

Answer 10

catalyze joining of a c-c bond

Question 11

apoenzyme

Answer 11

enzyme without cofactor

Question 12

haloenzyme

Answer 12

functional enzyme with cofactor

Question 13

Trypsin

Answer 13

Serine protease, cleaves at arginine and lysine (basic)

Question 14

Chymotrypsin (just what it cleaves)

Answer 14

serine protease cleaves at Phe, met, trp

Question 15

Thrombin

Answer 15

serine protease cleaving at arg-gly bonds

Question 16

ΔE*

Answer 16

Activation Energy without enzyme

Question 17

ΔGo

Answer 17

Free energy change

Question 18

ΔEo+

Answer 18

Activation Energy of the catalyzed reaction

Question 19

Properties of an Active Site (4)

Answer 19

Crevice Creates microenvironment
3D fold
Held by weak non-covalent interactions
small part of enzyme

Question 20

Proximity Affect

Answer 20

Brings substrates closer together

Question 21

Lock and Key

Answer 21

Enzyme Substrate Complement one another

Question 22

Induced Fit

Answer 22

Enzyme Changes shape as substrate binds give energy to reach state

Question 23

V in kinetics

Answer 23

Rate or change in [] of reactants or products over time

Question 24

K1 in Kinetics

Answer 24

Rate Constant of forward reaction

Question 25

K2 in kinetics

Answer 25

Rate constant of the reverse reaction

Question 26

Michaelis Menton Shape

Answer 26

is a hyperbolic curve

Question 27

Allosteric Enzyme Curve Shape

Answer 27

sigmoidal curve

Question 28

At low Concentration of S what is the rate compared

Answer 28

The rate is proportional to the concentration of S and is first order

Question 29

at high S concentration rate is compared how

Answer 29

At high S concentration rate is independed and zero order

Question 30

What are the three michaelis Menton Assumptions

Answer 30

1 - formation and breakdwon are constant and so at steady state
2- product formation is irreversible
3 - K2

Question 31

Km is what

Answer 31

the michaelis menton constant. It combines all rate constants for formation and dissappearance. It is the concentration of substrate when it is half maximum

Question 32

What is the Km formula

Answer 32

Km = (k2+K3)/K1

Question 33

What does a high Km or low Km mean

Answer 33

High Km means loose binding low km means tight binding

Question 34

Vformation =

Answer 34

K1[s][E]

Question 35

V breakdown =

Answer 35

(K2+K3)[ES]

Question 36

Kcat is

Answer 36

the rate constant for the formation of P

Question 37

Lineweaver Burke Plot Readings

Answer 37

X Axis - 1/[s]
Y Axis - 1/V
X intercept = -1/km
Y Intercept 1/V

Question 38

Sequential Displacement

Answer 38

Substrate binds before product is released

Question 39

Ping Pong double displacement

Answer 39

one or more products are released before all substrates are

Question 40

Reversible Types of Inhibition and explanation

Answer 40

Competitive - Binds enzyme in active site and has a similar structure to substrate
non-competitive - binds to a site not the active site to change conformation of enzyme

Question 41

Kinetics of Competitive Inhibitor

Answer 41

Km will be larger because affinity decreases
the Vmax does not change
Therefore a graph would have increasing slope on a lineweaver burke plot