Culture bacteria on solid medium
observe that only pseudomonas is luminous under near ultra violet lamp
culture bacteria on solid media for 36 hours
put a drop of 3% KOH on the objective glass
take a colony of the bateria by inoculation loop
suspend the bacteria on in 3%KOH on the objective glass
mix jently the baceria and the KOH solution for 2-5 min
Observe the slime formation:
No slime (negative) = gram positive
Slime formation (positive) = gram negative