ligate

Ligate is a verb meaning to bind or join things together. The term derives from the Latin ligare, “to bind.” In general usage, ligation refers to the act of tying off or binding, and it appears in both medical and laboratory contexts.

In molecular biology, ligation refers specifically to joining two DNA molecules end-to-end using a ligase enzyme. The goal is to create a continuous DNA strand by forming a phosphodiester bond between adjacent nucleotides. Ligation can involve cohesive (sticky) ends, blunt ends, or recursive ligation in repair and cloning workflows. Commonly used enzymes include T4 DNA ligase, which requires adenosine triphosphate (ATP) and a 5′ phosphate on the DNA ends. Ligation efficiency depends on end compatibility, DNA concentration, temperature and duration, and the presence of suitable cofactors. Applications include cloning inserts into vectors, plasmid construction, and library preparation. Designers often mitigate background from unwanted self-ligation by dephosphorylating vector ends or using incompatible overhangs.

In surgery and anatomy, ligation refers to tying off a vessel, duct, or other structure to stop blood flow or drainage. This is achieved with sutures, ligating clips, or other devices and is a common step in procedures such as vascular control, vasectomy, and tubal ligation.

Etymologically, ligate comes from Latin ligare, meaning to bind. The term appears across disciplines to denote joining, binding, or closing off components through chemical or mechanical means.