2.4 Enzymes

Question 1

Describe what bonds and iteracrions cam make an exnyme cjange its shape and wrap around a substrate more closely (induced fit hypothesis)

Answer 1

Interacrions between R groups cause the following bonds and interactions

Hydrogen and ionic bonds and disulphide bridges

Hydrophilic and hydrophobic

Question 2

What would cause a slow ROR or turnover number of an ezyme in a low temperature ?

Answer 2

-not enought Ek per enzyme
-Number of collisoons to form ESC is low so less substrates catalysed
Substrate concentration remains somewhat high

Question 3

What happens to an enzyme if temperature is too high?

Answer 3

Denatures as molecule VIBRATES and bonds BREAK changing shape of AS so subrate can no longer fit so enzyme denatured

Question 4

How is starch digested?

Answer 4

Start is composed of amylopectin and amylose which have specific substrate shapes . It requires 2 enzymes each specific and complementrary to each sugar molecules substrate and starch is first converted to maltose then glucose

Question 5

How do cofactors increase ROR?

Answer 5

They bind to enzyme (typically at AS) and activate enzyme

Question 6

Explain the lock and key hypothesis and its relarionship to enzyme structure

Answer 6

Lock and key hypothesis is a description of the shape of AS being caused by the specific sequence of AA which produces a specific teritary structure thats 3D.

The LKH explains how enzymes are specific to their substrate

Question 7

Explain the course of an enzyme controlled reaction

Answer 7

enz+sub->enz-sub comp->enz-prod comp->enz+pro

E +S –> ESC –> EPC –> E + P

Question 8

Give 4 conditions and effects of enzyne related reactions

Answer 8

• pH : bell shaped
• temperature : bell shaped
• enzyme conc : linear eith gradient being turnover rate
• substrate conc : linear then plateaus as enzyme concentration may be a limiting factor

Question 9

Name 4 types of inhibitors

Answer 9

Competitive 
Non competitive 
Reversible
Non reversible
Product inhibitor