antibiotics nucleic acid inhibitors

they inhibit bacterial DNA or RNA synthesis, preventing protein production and replication, which leads to bacterial cell death.

What is the overall mechanism of nucleic acid synthesis inhibitors?

Bacterial enzymes involved in DNA and RNA synthesis are DIFFERENT from human enzymes, they target bacteria without causing major harm to human cells.

Why are nucleic acid synthesis inhibitors selectively toxic to bacteria?

• Metronidazole

• Quinolones (Fluoroquinolones)

• Rifamycins

What are the three major classes of nucleic acid synthesis inhibitors?

Metronidazole (nucleic acid synthesis inhibitors)

Uses: anaerobic infections below the diaphragm (i.e., C. difficile colitis, diverticulitis) and protozoans

MOA

metabolized by bacteria into reduced reactive compounds that damage DNA, proteins, etc killing the cell

Side Effects and interventions

• Headache

• Nausea

• Metallic taste

DO NOT USE ALCOHOL CAUSES disulfiram-like reaction (REACTION CONSUMING ALCOHOL),

They inhibit DNA gyrase (topoisomerase II) and topoisomerase IV, blocking DNA replication and causing bacterial cell death.

What is the mechanism of action of Quinolones?

Fluoroquinolones contain a fluorine atom that increases antimicrobial activity.

What is the difference between quinolones and fluoroquinolones?

Name five fluoroquinolones.

• Ciprofloxacin(often used for UTIs and anthrax)

• Levofloxacin(frequently used for pneumonia and sinus infections)

• Moxifloxacin (used for respiratory and intra-abdominal infections)

• Norfloxacin

• Ofloxacin

fluoroquinolones

effective against gram - bacteria, FOR UTIS, GI INFECTIONS, RESPIRATORY INFECTIONS

MOA: inhibit bacterial DNA topoisomerase II

Sides effects

• Nausea

• Vomiting

• Diarrhea

• Headache

• Insomnia

BLACKBOX WARNINGS

• tendonitis and tendon rupture

• QT prolongation

• Peripheral neuropathy

What NCLEX warning should you remember about fluoroquinolones?

They can cause tendon rupture and peripheral neuropathy.

Name three Rifamycins.

• Rifampin

• Rifabutin

• Rifapentine

Rifamycins

used for MYCOBACTERIUM AND some GRAM- (Neisseria meningococcus)

MOA:

inhibit bacterial RNA polymerase, preventing RNA synthesis (transcription)

Side effects

• harmless orange color in urine and sweat/tears

• thrombocytopenia (low platelets)

• nephritis

• hepatitis

They inhibit bacterial DNA-dependent RNA polymerase, preventing RNA synthesis (transcription).

What is the mechanism of action of Rifamycins?

• Metronidazole: Metallic taste + No alcohol

• Fluoroquinolones: Tendon rupture + QT prolongation

• Rifampin: Orange-red body fluids + Hepatotoxicity

What are the classic "buzzwords" for nucleic acid synthesis inhibitors?

Metronidazole is a prodrug that is activated inside anaerobic bacteria to form toxic free radicals that damage bacterial DNA, causing strand breaks and cell death.

What is the mechanism of action of Metronidazole?