Diagnostic device > Other diagnostic sets
DIAGNOSTIC SETS 50 tests Code: SO 341
ITEST PYR TEST
for rapid identification of enterococci, group A streptococci and differentiation of Staphylococcus haemolyticus from S.auricularis
Purpose and usage:
PYR TEST set is designed for the rapid differentiation of enterococci from group D ß-hemolytic strepto cocci. It is possible by this test to differentiate easily and rapidly group of A ß-hemolytic streptococci from other groups of ß-hemolytic streptococci and also differentiate some staphylococci (positive S. haemolyticus from negative S. auricularis).
Principle:
Principle of the test is the detection of pyrrolidonyl peptidase activity (PYRase) which is characteristic for all species of enterococci in contrast to group D streptococci with no such activity. Among other strepto-cocci, PYRase is produced only by Streptococcus pyogenes (group A).
Technique:
Wet the PYR TEST disc on the strip with 10 µl sterile distilled water. Put 5-10 colonies of the tested strain from a 24 hrs culture on the surface of the disc with a loop and smear them lightly on it.
Incubate the disc 1-2 minutes at room temperature.After incubation place one drop of the color developer on the disc and wait for one minute (the color developer must have room temperature).
Evaluation:
If the reaction is positive (PYRase +), the inoculated part of the disc will be colored pink, red or red-violet within 1 minute. If the reaction is negative (PYRase -) the inoculated part of the disc stays after the application of the developer without change of color or turns creamy or yellow.
NOTE. A weak color can be caused by a small inoculum or weak production of PYRase (only individual strains) if the reaction is positive. Repeat the test with a heavier inoculum if it is necessary.
Warning:
1. PYR TEST set is delivered in pack of 50 tests and is designed for the laboratory use only.
2. Keep the set in a dark place at +4°C and use it until the expiration date marked on the package. Protect the color developer from direct sun light.
Take care not to touch skin and eyes with the disc and color developer. Wash the contaminated spot immediately with running water.
