The main test to distinguish strep spp. from staph spp. is the
catalase test. Staph spp. are catalase + whereas strep spp. are
catalase -.
ANSWER
There are numerous test that are used to differentiate
streptococci from Staphylococci. Just to name a few:
Although they are both Gram Positive, their morphology
(structures) are obviously different. Under a microscope strep
usually looks like a chain of cocci while staph looks like a
cluster of grapes formation.
Lab test will show obvious differences in their hemolytic
activity. For example, test will show the presence of leukocidin
and staphylokinase (substances that are specific to staph
bacteria).
Test will also show suscetability of staph bacteria to the
antimicrobial agent Novobiocin. Test will aslo show staph reaction
to carbohydrate mannitol.
There are many other test that will differentiate the two
bacteria, this was just to name a few.
