Molecular Classification
Enzyme, Hydrolase, Beta-Lactamase
Other Names
AmpC beta-lactamase, Class C β-lactamase, AmpC-type β-lactamases, Group 1 cephalosporinases
Disease Roles
InfectionAntibiotic resistance

Class C Cephalosporinase Overview

Class C cephalosporinases, also known as AmpC β-lactamases, are enzymes produced by various Gram-negative bacteria. Their primary function is to hydrolyze and inactivate a broad range of β-lactam antibiotics, particularly cephalosporins. These enzymes play a significant role in antibiotic resistance. They are typically encoded by chromosomal genes but can also be found on plasmids. Expression is often inducible. Class C cephalosporinases are widespread among Gram-negative bacteria, including Enterobacter, Citrobacter, Serratia, Proteus, Pseudomonas aeruginosa, and some strains of E. coli, making them major contributors to hospital-acquired infections with multidrug-resistant phenotypes. Classic inhibitors such as clavulanic acid do not inhibit class C enzymes effectively; however, newer agents like avibactam show inhibitory activity.

Mechanism of Action

Antibiotic inactivation

Biological Functions

Antibiotic resistance
Hydrolysis of beta-lactam antibiotics

Disease Associations

Infection
Antibiotic resistance

Safety Considerations

  • Multidrug resistance
  • Hospital-acquired infections

Interacting Drugs

Penicillins
Cephalosporins
Monobactams
Aztreonam
Cefepime
Avibactam
Clavulanic acid
Tazobactam
Cefotaxime
Ceftazidime