∞ generated and posted on 2016.02.20 ∞

Enzyme that converts prothrombin to thrombin, a process normally seen only in the course of blood clotting.

Coagulase is an enzyme associated with certain bacteria – such as the notably coagulase-positive Staphylococcus aureus – that causes blood to coagulate, that is, to clot.

More generally, a coagulase is simply an enzyme that has the property of being able to cause to clot, e.g., thrombin.

Blood clotting more technically is known as . It is a property not just of blood but also of , i.e., blood minus cells, that is, minus the including minus the . , by contrast, does not have this property (as serum is produced from clotted blood).

The enzyme coagulase is what is tested for in microbiology's . Staphylococcus is notably coagulase positive which differentiates it from other, particularly less pathogenic staphylococci such as .

Coagulase may serve as a Staphylococcus virulence factor and the form of thrombin produced by Staphylococcus coagulase is called . Coagulase is also associated with the -causing bacterium, Yersinia .

Despite the background noise, the following is a nice, to-the-point description of a slide-based coagulase test:

The following video is much more detailed, but also longer: