Catalysing Life: Lecture 1

Question 1

spontaneous reaction:
- favourable/unfavourable
- positive/negative ΔG

Answer 1

favourable
negative

Question 2

when an enzyme requires a non-protein component,
what is the enzyme alone called and what is the complete enzyme called?

Answer 2

apo-enzyme
halo-enzyme

Question 3

what 3 ways can enzymes be regulated?

Answer 3

proteolysis
covalent-modification
allosteric regulation

Question 4

what is proteolysis?
+ give 2 examples

Answer 4

1 way on switch e.g. digestive enzymes, blood clotting cascase

Question 5

what is covalent modification?
+ give an example

Answer 5

2 way on/off switch
phosphorylation

Question 6

what is allosteric regulation?

Answer 6

graded response to either substrate or non-substrate

Question 7

what are 3 types of enzyme-substrate complexes/molecular recognition?

Answer 7

lock-key
induced fit
conformational selection

Question 8

transition state defintion

Answer 8

tightest substrate + enzyme interaction
least stable chemical substrate form

Question 9

what are amino acids’ (that are not in active site) function? (3)

Answer 9

1. position active side AA
2. provide micro-enviro
3. provide other sites for recognition + control