Commonly detection of free coagulase is by tube test and bound coagulase is by slide test.

Original information:

Comparison of the slide and tube tests

A comparison of the slide test with the test used in the present work for

bound coagulase, under varied conditions, showed no discrepancies. The slide

test is therefore due to bound preformed coagulase on the cells. Under the

conditions used by Linsell & Gorrill (1951) this acts on plasma treated by

heat or with thiomersalate and causes clumping of the cells.

By contrast the tube test requires the production of a clot, which is a

function of free coagulase. Experiments have shown that even with a good

coagulase-producing strain of staphylococci, insufficient free coagulase would

be carried over in the inoculum used by Linsell & Gorrill (1951); hence a

positive result must be due to the production of free coagulase during the

2 hr. incubation period. This was of course impossible in the presence of

1/10,000 thiomersalate; the cells failed to grow and the test was negative.

Tests of plasma treated with 1/10,000 thiomersalate for 24 hr. have shown no

loss of activator, and a minor change in the fibrinogen as indicated by a slight

delay in the reaction when treated with bound coagulase, free coagulase or

thrombin.

Thank you for information.

Are there any other ways of testing?

No. But one can go for gene based indirect detection.

To add the preferred one/ or one which is supposed to be used is rabbit plasma for the test. Further the animal strains- one which cause animal infections only (eg., S. hyicus and S. intermedius) also test positive for coagulase enzyme.

Hi , Dr .Shishir Gokhale