enzyme kinetics

Question 1

what is kinetics

Answer 1

study of reaction rates and how
they change in response to changes in
experimental parameters

Question 2

name one key factor affecting rate of reaction

Answer 2

concentration [amount of substrate present]

Question 3

when is Vo measured

Answer 3

@ start of reaction - little substrate has been converted -> product

Question 4

Vo increases linearly with x but this rate slows down when?

Answer 4

an increase in the substrate - when more of the enzyme is used up until enzyme= saturated and is working @ its max. capacity # Vmax

Question 5

what is Km

Answer 5

Michaelis-menten constant- the required substrate for enzyme to reach half Vmax

Question 6

the lower the Km the…

Answer 6

tighter the substrate binds -> the enzyme// high affinity for substrate

Question 7

enzyme inhibition is the goal of the pharmaceutical industry - give an e.g.

Answer 7

Aspirin inhibits cyclooxygenase, stops prostaglandin
synthesis and inhibits pain.
b) Statins inhibit HMG-CoA reductase in liver (which
makes cholesterol) controls heart disease.
c) Taxol inhibits microtubule protein prevents mitosis
and inhibits cancer

Question 8

when developing a drug how does kinetics come into play

Answer 8

the rate at which the drugs effects the reaction can be obtained

Question 9

enzyme kinetics is the study on chemical reactions that are catalysed by enzyme with a focus on their -

Answer 9

reaction rates

Question 10

3D Modeling is useful when?

Answer 10

looking @ interaction between inhibitor and enzyme active site- helps design new drugs

Question 11

structural information can aid drug development by? x3

Answer 11

1. Providing information on the enzyme active site and its dimensions
   2.The nature of amino acid groups in the active site participating in catalysis.
2. The nature of groups at the active site participating in substrate binding.

Question 12

how can it be determined if an enzyme has an inhibitions

Answer 12

examine enzyme reaction in the presence of the potential inhibitor

Question 13

hat are the 3 types of inhibition

Answer 13

-competitive inhibition
-non-competitive inhibition
-un-competitive inhibition

Question 14

what other factors effect rate of an enzyme reaction

Answer 14

1) pH, enzymes operate within a range of pH optima outside this range the
enzyme activity may fall off. This may be due primarily to the ionisation of
groups at the active site which participate in binding or catalysis.
2) Heat, Enzymes as with all proteins are held together by forces such as
hydrogen bonding which are liable to be broken by heat. Thus heat can
result in chain unfolding and denaturation

Question 15

the initial reaction velocity Vo is equal to?

Answer 15

rate at which the enzyme substrate complex is broken down

Question 16

Km =?

Answer 16

substrate concentration @ which reaction velocity = 1/2 max

Question 17

what are on the axis of the lineweaver-Burk plot

Answer 17

1/Vo - y-axis versus - 1/S- x-axis

Question 18

Hanes-Woolf Plot has what on the axis

Answer 18

S - Y-axis and S/Vo on x-axxis

Question 19

a high vmax means

Answer 19

quick rate of reaction

Question 20

a low Km fast enzyme concentration eg.

Answer 20

2 x 10^-6 mM [binds more tightly]

Question 21

a high Km slow enzyme e.g. concentration

Answer 21

2 x 10^-2 mM

Question 22

which types of drugs are more specific and which type pf drugs have the best inhibition

Answer 22

more specific - competitive inhibitors
uncompetitive drugs = best inhibition

Question 23

the higher the enzyme affinity for a drug effects concentration how

Answer 23

higher the affinity the lower the concentration that can be used - the lower the dosage the better

Question 24

binding affinity is determined by?

Answer 24

Km

Question 25

what general type of enzyme is EC2.7.1.2

Answer 25

glucokinase