Question

discuss two ways in which drugs prevent the attachment of natural substrate on active sites of enzyme

Answer 1

When drugs are taken, they block the binding sites of the enzymes and hence prevent the substrate from binding or can inhibit the catalytic activity of the enzymes. It can be done in 2 ways:

1) Drugs compete with natural substrate for attachments on active sites. Such drugs are known as competitive inhibitors.

2). Some drugs don't bind to enzyme's active site. They bind to a different site called allosteric site (see image below). This allosteric site changes the shape of active site in a way that substrate can't recognize it and hence not bind to it.

Answer 2

Drugs inhibit the attachment of substrate on active site of enzymes in two different ways :

(i) Drugs compete with the natural substrate for their attachment on the active sites of enzymes. Such drugs are called competitive

inhibitors.

ii) Some drugs do not bind to the enzyme’s active site. These bind to a different site of enzyme which is called allosteric site.This binding of inhibitor at allosteric site changes the shape of active sites in such a way that substrate can not recognise it.