Antibiotics & Mechanisms of Action

Flashcards on cell wall and cell membrane drugs

Peptidoglycan (PG)

Provides shape and rigidity to bacteria.

Undecaprenol

A molecule linked by a pyrophosphate to the PG building block.

NAG-NAM

A disaccharide found in the PG building block.

Lipid II

The unit of peptidoglycan flipped across the cytoplasmic membrane.

UTP

Uridine triphosphate.

PEP

Phosphoenol pyruvate.

NADPH

Reduced nicotinamide adenine dinucleotide phosphate.

A2 pm or DAP

Diaminopimelic acid.

Ala

Alanine.

Glu

Glutamic acid.

GlcNAc

N-acetylglucosamine.

MurNAc

N-acetylmuramic acid.

FtsW, MurJ, and AmJ

Bacterial flippase candidates.

MurG

Synthesizes lipid II from lipid I and UDP-NAG.

Lipid II flippase

Translocates lipid II across the inner membrane.

Transglycosylases (TG)

Polymerize the disaccharide-pentapeptide into glycan chains.

TPs

Catalyze peptide bonds between stem peptides in adjacent glycan chains.

CPs

Remove the terminal d-Ala residue of stem peptides.

Bacitracin

Inhibits the dephosphorylation of bactoprenol.

Bacitracin

Made by non-ribosomal peptide synthesis; used topically against gram-positives.

Nonribosomal Peptide Synthetases (NRPS)

Large enzyme complexes used in nucleic-acid-independent synthesis.

Glycopeptide antibiotics

Bind D-Ala-D-Ala and inhibit transglycosylase.

Vancomycin, Teicoplanin

Examples of Glycopeptide antibiotics.

Penicillins, Cephalosporins, Carbapenems, Monobactams

β-lactams that inhibit transpeptidation.

Polymyxins and colistin

Destroy bacterial cell membranes, active against Gram-negatives.