A macrocyclic peptide deformylase (PDF) inhibitor comprising a peptide or peptide mimetic having three residues, P1', P2', and P3', wherein P2' connects P1' and P3', wherein P1' and P3' each have a side chain, and wherein the side chains on P1' and P3' are crosslinked to form the macrocyclic PDF inhibitor. The side chains of P1' and P3' interact with the PDF active site, and preferably, P2' has a side chain that interacts with a solvent. Also provided are methods of inhibiting the growth of a bacterium, the methods comprising contacting the bacterium with an anti-bacterial effective amount of the inventive macrocyclic PDF inhibitor. Additionally, a method of treating a bacterial infection in a subject comprising administering an effective amount of a macrocyclic PDF inhibitor to a subject in need of treatment. Additionally, methods of preparing macrocyclic PDF inhibitors comprising a) choosing an acyclic base molecule, having at least some PDF inhibitory activity, the acyclic base molecule having a first residue having a first side chain that interacts with the PDF active site and a second residue having a second that interacts with the PDF active site; and b) crosslinking the first side chain and the second side chain to form a macrocyclic PDF inhibitor.