Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Penicillins are a group of antibiotics derived from Penicillium fungi, effective against many Gram-positive bacteria. They inhibit bacterial cell wall synthesis, leading to cell lysis and death.
5 Must Know Facts For Your Next Test
Penicillins target the bacterial enzyme transpeptidase, essential for cell wall synthesis.
They are primarily effective against Gram-positive bacteria but have limited efficacy against Gram-negative bacteria.
Commonly used penicillins include penicillin G, penicillin V, amoxicillin, and ampicillin.
Bacterial resistance to penicillin can occur through the production of beta-lactamase enzymes that break down the antibiotic.
Penicillins can cause allergic reactions in some individuals, ranging from mild rashes to severe anaphylaxis.
Review Questions
Related terms
Beta-lactamase: An enzyme produced by certain bacteria that breaks down beta-lactam antibiotics like penicillin.
Transpeptidase: A bacterial enzyme targeted by penicillins that is crucial for synthesizing the bacterial cell wall.