Pyrase / BBL™ DrySlide
Pyrrolidonyl Arylamidase (PYR) test is a rapid test which is used for the presumptive identification of group A beta-hemolytic Streptococci and Enterococci.
The substrate for the PYR test is L-naphtylamide-ß-naphtylamide wich is hydrolyzed by a specific bacterial enzyme.
Hydrolysis of the substrate by this enzyme releases free ß-naphtylamide, which is detected by the addition of N,N-dimethylaminocinnamaldehyde.
This detection reagent couples with the naphthylamide to form a red Schiff base.
Procedure of PYR test
The Dryslide contain dried chromogenic substrates for pyrrolidonyl peptidase (PYRase) and beta-gluconidase.
1. Applie only a few colonies to the test strip
2. After 2 minutes
3) Positive: S. pyogenes, E. faecalis and E. faecium
Negative: No color change or a blue color due to a positive indole reaction.
Group B Streptococci (Streptococcus agalactiae), Streptococcus mitis, S. bovis, S. equinus, S. milleri.
Note: A pale pink reaction (weak) is considered negative.