Question:
The question is unclear but I think I found it elsewhere and have rewritten it below:
Enzyme X has a primary structure made up of 130 amino acids. In tertiary structure amino acids numbers 56, 58, 81-84, and 91-95 form the active site.
Looking at the data in the attached table, determine the category of unknown molecules A, B and C.
1) A = cofactor B = non-competitive inhibitor C= non-competitive inhibitor
2) A = competitive inhibitor B = not a cofactor C= non-competitive inhibitor
3) A = not a cofactor B = competitive inhibitor C= non-competitive inhibitor
4) A = non-competitive inhibitor B = non-competitive inhibitor C= competitive inhibitor
5) A = competitive inhibitor B = non-competitive inhibitor C= non-competitive inhibitor
Answer:
2) A = competitive inhibitor B = not a cofactor C= non-competitive inhibitor
Explanation:
A competitive inhibitor is a molecule that binds to the active site of an enzyme, directly blocking its ability to catalyse reactions and thus inhibiting its activity. A non-competitive inhibitor inhibits the activity of an enzyme, but not through binding an active site. A co-factor is an accessory protein that influences and promotes the activity of the enzyme
The table shows that unknown molecule A binds to the active site (based on the amino acid positions at which it binds) and reduces the activity of the enzyme (from 31.8 - 11.4) - <em>a competitive inhibitor </em>
Unknown molecule B does not bind at the active site, and has no affect on the activity of the enzyme - <em>not a co-factor or an inhibitor</em>
Unknown molecule C does not bind to the active site, but strongly reduces the activity of the enzyme - a<em> non-competitive inhibitor</em>
