Cefiderocol

Cefiderocol acts by binding to and inhibiting penicillin-binding proteins (PBPs), preventing cell wall synthesis and ultimately causing death of the bacterial cell. Like other β-lactam antibiotics cefiderocol is able to enter bacterial cells via passive diffusion through porins. Unlike other β-lactams, cefiderocol contains a chlorocatechol group which allows it to chelate iron. Once bound to ferric iron cefiderocol is able to undergo active transport into bacterial cells through iron channels in the outer cell membrane such as those encoded by the cirA and fiu genes in E. coli or the PiuA gene in P. aeruginosa. Once inside the cell, cefiderocol binds to and inhibits PBP3 with high affinity thereby preventing the linking of peptodoglycan layers via the pentapeptide bridge. PBP1a, 1b, 2,and 4 are also bound and inhibited by cefiderocol but with a lesser potency than PBP3 and are therefore expected to contribute less to its antibacterial effect.