Proteus

Lab Fifteen :- _______________ Medical Microbiology
Prepared by: Luma J. Witwit

Group: proteus : P. vulgaris, P. mirabilis .
Morganella : M. morganii
Providencia: P. Stuartii, P. rettgeri

Proteus :-
Gram negative bacilli , non capsulated , actively motile , coli- form bacteria , polymorphism , and because of the motility can not isolate this bacteria as discrete colonies on solid media due to" Swarming phenomena " which means the media covered by larger of Proteus growth as circular lines with one center under aerobic conditions .
To prevent swarming or to isolate single colony of proteus must be increase agar medium or by decreasing of ions of medium as in (cysteine-lactose-electrolyte deficient medium) .
Proteus mirabilis causes 90% of Proteus infections and can be considered a community-acquired infection. Proteus vulgaris and Proteus penneri are easily isolated from individuals in long-term care facilities and hospitals and from patients with underlying diseases or compromised immune systems.
Diseases:-
Urinary tract infection (Mostly), wound infection, bacteremia.

Lab diagnosis:-
1- Gram stain (G-bacilli )
2- Mac Con key agar (NLF), pale colonies.
3- Blood agar : observed swarming with fishing odor colonies.
4- TSI
5- IMVIC
6- Unease test
7- Gelatin agar (protease)
8- Deaminase test
9- Sucrose fermentation.
Proteus are divided into 2 groups based on H2S Production :
H2S positive
P. vulgaris : indol+ , Urease +
P. mirabilis : indol - , Urease -
H2S negative .
a) M. morganii : Urease+ .
Providencia : Urease v .