2 Antimicrobial Drugs and Disinfection Testing

Inhibition of Cell Wall Synthesis

Drugs that target the synthesis of bacterial cell walls, which humans do not have.

Beta-lactams

Drugs like Penicillins and Cephalosporins that bind to enzymes that cross-link NAM subunits in peptidoglycan.

Vancomycin

Interferes with the alanine-alanine bridges between NAMs.

Isoniazid (INH)

Targets mycolic acid synthesis, specific to Mycobacterium like TB.

Inhibition of Protein Synthesis

Targets differences between bacterial 70S ribosomes and human 80S ribosomes.

30S Subunit Targets

Includes Aminoglycosides (change shape of 30S) and Tetracyclines (block the tRNA docking site).

50S Subunit Targets

Includes Chloramphenicol (blocks peptide bond formation) and Macrolides like Erythromycin (stops ribosome movement).

Mupirocin

Specifically targets the enzyme that charges tRNA with the amino acid isoleucine in Gram-positive bacteria.

Disruption of Cytoplasmic Membranes

Drugs that affect the integrity of bacterial membranes.

Polyenes

Drugs like Amphotericin B that bind to ergosterol in fungal membranes.

Polymyxin

Destroys membranes of Gram-negative bacteria and is often used topically.

Inhibition of Metabolic Pathways

Drugs that interfere with bacterial metabolism.

Sulfonamides

Act as structural analogs of PABA, which bacteria need to make folic acid.

Inhibition of Nucleic Acid Synthesis

Drugs that target the synthesis of nucleic acids in bacteria or viruses.

Quinolones

Inhibit DNA gyrase, which is needed for bacterial DNA coiling.

Nucleoside Analogs

Fake building blocks that viruses incorporate into their DNA/RNA, causing mutations.

Phenol Coefficient

A ratio comparing an agent's effectiveness to phenol (>1.0 is better than phenol).

Use-Dilution Test

Current U.S. standard that uses metal cylinders dipped in bacteria.

Kelsey-Sykes Capacity Test

European standard that measures the time needed for effectiveness.

In-Use Test

Most realistic test using swabs taken from actual environments before and after cleaning.