Question

A patient states, “My bacteria are immune to penicillin.”  Is this accurate? Why or Why not?

Answer 1

Answer--

Bacterial cell wall synthesis exclude cross linking of polypeptide chain for the stability. In the bacterial cell wall L- ala, D-glu, L-lys and D - ala are connected to N-acetyl glucosamine (three unusual amino acids are D-glu, D-ala, D-ala are found) . This cell wall linking is done by the bacterial enzyme transpeptidase. For the inhibition of transpeptidase use the pencillin. In the pencillin the active compound is Beeta lactum ring. So the transpeptidase oxidazese beeta lactum ring of pencillin and ring open. Now the transpeptidase irreversibly inhibited by pencillin.

So in this case bacteria also evolved or express (pencillin resistance bacteria) another enzyme Beeta lactamase and inactivate pencillin. So another salt is added cavulanic acid these bind to beeta lactamase and beeta lactum ring of pencillin bind to transpeptidase of bacteria. So the bacterial cell wall synthesis are inhibited. In this mechanism all inhibition are covalent and irreversible.