Cephalosporins

The cephalosporins are a class of β-lactam antibiotics originally derived from the fungus Acremonium, which was previously known as Cephalosporium. Together with cephamycins, they constitute a subgroup of β-lactam antibiotics called cephems. See also Cephalosporin.

Cephalosporins are bactericidal and, like other β-lactam antibiotics, disrupt the synthesis of the peptidoglycan layer forming the bacterial cell wall. The peptidoglycan layer is important for cell wall structural integrity. The final transpeptidation step in the synthesis of the peptidoglycan is facilitated by penicillin-binding proteins (PBPs). PBPs bind to the D-Ala-D-Ala at the end of muropeptides (peptidoglycan precursors) to crosslink the peptidoglycan. Beta-lactam antibiotics mimic the D-Ala-D-Ala site, thereby irreversibly inhibiting PBP crosslinking of peptidoglycan.^[1]

Cephalosporin C (β-lactam ring is in salmon) was a lead compound for the discovery and production of many other cephalosporins.

Examples:

• Cefepime
• Cefotaxime
• Ceftazidime
• Ceftriaxone

See also:

• Cephalosporin acylase
• Cephalosporin C deacetylase