enzyme kinetics

Question 1

what do the symbols [S], V, Vmax and Km stand for

Answer 1

[S] = conc. of substrate
V = rate of catalysed reaction
Vmax = maximum rate of reaction
Km = half of maximum rate of reaction

Question 2

describe the different types of enzyme inhibition

Answer 2

reversible inhibition in form of competitive and non-competitive
irreversible in form of non-competitive
feedback inhibition

Question 3

describe the effects of competitive inhibition of the Lineweaver-Burk plot of an enzyme

Answer 3

the Vmax does not change but the Km varies

Question 4

describe the effects of non-competitive inhibition on the Lineweaver-Burk plot of an enzyme

Answer 4

the Vmax varies but the Km does not change

Question 5

what can be used to control enzyme kinetics

Answer 5

allosteric inhibitors and activators

Question 6

what effect does increasing [S] have on the V of an allosteric enzyme graph

Answer 6

creates a sigmoidal ( shallow S shaped) curve rather than a hyperbola

Question 7

what do allosteric factors show and do

Answer 7

they show co-operative behaviour and modulate enzyme kinetic behaviour

Question 8

describe feedback inhibition of an enzyme

Answer 8

the inhibition of rate limiting enzymes by end products, common mechanism of allosteric control