Past and Present Perspectives on β-Lactamases.

Area of Science:

• Microbiology
• Biochemistry
• Genetics

Background:

• Beta-lactamases are primary determinants of beta-lactam antibiotic resistance in Gram-negative bacteria.
• These enzymes have ancient origins, evolving from environmental sources likely as a defense mechanism against naturally occurring beta-lactams.

Purpose of the Study:

• To provide a comprehensive overview of beta-lactamase enzymes, including their origins, classification, and clinical significance.
• To highlight the challenges posed by newly emerging beta-lactamase variants.

Main Methods:

• Review of existing literature on beta-lactamase enzymes.
• Analysis of enzyme classification systems (functional, sequence-based, and combined nomenclature).
• Discussion of clinical implications and emerging variants.

Main Results:

• Beta-lactamases are ancient enzymes with diverse origins and functions.
• Current classification systems include functional, sequence-based (Classes A-D), and combined nomenclature.
• Problematic enzymes like ESBLs and carbapenemases necessitate new therapeutic strategies.

Conclusions:

• The continuous emergence of new beta-lactamase variants, often lacking phenotypic data, complicates clinical management and antibiotic research.
• Ongoing surveillance and characterization of beta-lactamases are essential for effective antimicrobial stewardship.