A microbiologist was surprised when he could not recover Helicobacter pylori from gastric biopsies in which organisms were seen in the tissue sections. He was advised to switch from the Campy BAP selective medium to Skirrow's blood agar because the latter is free of cephalothin.
A broad-spectrum cephalosporin antibiotic called cephalothin is used to treat severe bacterial infections in the urinary tract, skin, bones, and lower respiratory tract.
A beta-lactam, first-generation cephalosporin antibiotic with bactericidal activity, cephalothin is semi-synthetic.
Penicillin-binding proteins (PBP) on the inner membrane of the bacterial cell wall are bound by cephalothin and rendered inactive.
PBPs take involvement in the last phases of bacterial cell wall construction as well as the remodeling of the cell wall during cell division.
PBP inactivation hinders the cross-linking of peptidoglycan chains, which is essential for the strength and stiffness of bacterial cell walls.