Puzzling Staphylococcus Species

Coagulase are enzymes that coagulate blood plasma by a mechanism that is similar to regular clotting. This enzyme is a reliable predictor of pathogenic potential of bacterium. Staphylococcus aureus is the only significant bacterium that produces coagulase and causing human disease.

The highly pathogenic Staphylococcus aureus can be distinguished from the other less pathogenic staphylococcal species by one method that is coagulase test. The majority of Staphylococcal species strains produce two forms of coagulase: bound and free. And different testing procedures are employed to evaluate each form because each one has specific characteristics.

It was shown that using several testing techniques contradicted the widely held belief that any degree of coagulase plasma coagulation signifies a positive diagnosis of Staphylococcus aureus. The distinction in staphylococcus species between slide coagulase and tube coagulase surely confused the laboratory expert in trying to obtain the correct result. These ever-changing distinctions demonstrated that Staphylococcus aureus is not the only coagulase-positive bacterium.

References

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