Question

Describe the mechanism of action and target one of the classes of antibiotics discussed in lecture. Provide a specific example of an antibiotic that falls under the chosen class and describe one way that resistance occurs within the microbial population. Briefly describe why microorganisms produce antibiotics in the environment. 

Answer 1

Penicillin inhibits activity of enzymes that are needed for the cross linking of peptidoglycans in bacterial cell walls, which is the final step in cell wall biosynthesis. It does this by binding to penicillin binding proteins with the beta-lactam ring, a structure found on penicillin molecules.

Example amoxicillin

There are two ways by which bacterial cells can acquire antibiotic resistance.
One is through mutations that occur in the DNA of the cell during replication.
The other way that bacteria acquire resistance is through horizontal gene transfer.