CRISPR-Cas opens a new era of antimicrobial therapy as a powerful gene editing tool.

The emergence of antimicrobial resistance (AMR) and the slow pace of new antibiotic development have contributed to an increase in mortality from bacterial infections, posing a significant threat to human health worldwide. In light of this, there is an urgent need to develop novel antimicrobial agents to complement or replace antibiotics. Clustered regularly interspaced short palindromic repeats-CRISPR-associated protein (CRISPR-Cas) technology, with its powerful and efficient gene-editing capabilities, has emerged as a promising novel antimicrobial agent to combat AMR. CRISPR-Cas systems can be delivered into bacteria in a variety of ways, targeting specific genes and killing bacteria with high precision without affecting normal flora. Bacteriophages (or phages) are another promising antimicrobial agent due to their specific bactericidal effects. CRISPR-Cas technology can also be used to edit phage genomes and alter phage properties, including addressing the limitations of phage therapeutic applications such as expanding the host range and enhancing bactericidal properties. This paper summarizes the composition and mechanism of action of different CRISPR systems, vectors for delivery of CRISPR systems, and their advantages and limitations. It also provides an overview of recent progress in the application of CRISPR-Cas systems to combat antimicrobial resistance and enhance the bactericidal properties of phages.