Micro-Unknown Research

Report Form for Gram-Positive Unknown Unknown ID Code: 2

MORPHOLOGICAL FEATURES (observations and results):

*Gram Stain Reaction: Gram-positive; the crystal violet was trapped inside the cell ____

*Cell Morphology and Arrangement: Staphylococcus ______________________________

Acid-fast Stain: _N/A_______________________________________________________

Capsular Stain: _ N/A______________________________________________________

*CULTURAL CHARACTERISTICS (observation of colonies on TSA and original unknown broth)

Cultural characteristics in broth: _sediment- accumulation of growth at the bottom of the tube _

Colony Form:_at 37° C= circular & at 25° C= punctiform_______________________________

Colony Size in mm: _ at 37° C= 1.5 mm & at 25° C= 0.5 mm____________________________

Colony Margin: Entire _________________________________________

Colony Texture: _Butyrous- buttery/smooth ______________________________

Colony Elevation:_Flat/ Slightly raised _________________________________________

Colony Surface Appearance:_Glossy and smooth- also opaque___________________________

Colony Pigment:_(+ or -)__+/- (both)  _ Color: at 37° C= yellow & at 25° C= beige_ H2O soluble? insoluble

PHYSIOLOGICAL CHARACTERISTICS: For lines that just have blanks, include observations and results

*Catalase:_bubbles formed which indicates the liberation of molecular oxygen as gas- positive results

*Glucose Fermentation Broth: A(acid)- appeared yellow due to the pH dropping (positive results) and

fermentation [of carbohydrates] took place- no gas

*Lactose Fermentation Broth:_Same as above—A(acid)- appeared yellow (positive results) so fermentation

took place- no gas

*Sucrose Fermentation Broth:_ As above—A(acid)- appeared yellow (positive results) so fermentation took

place- no gas

*Mannitol Fermentation Broth:_ As above—A(acid)- appeared yellow (positive results) so fermentation took

place- no gas

* Nitrate Reduction ( + or -) :__+__; observation after addition of:

Reagent A&B(color):_ became red showing NO2- is present____ zinc (color):__N/A__

*Hemolysis (circle one): + or - ; _ N/A_; _strongly Beta: complete destruction of the red blood cells and a

clear zone can be seen around the colonies—especially around the stab marks_ ; _ N/A_

Motility:____ N/A_____________

*Required Tests. All other tests are follow-up tests that depend on the results of the required tests. Be sure that you have carried out all of the appropriate follow-up tests that pertain to your organism (see pg 296 in the lab manual).

Mannitol salt agar: 7.5% Salt tolerance: __positive/abundant growth (colonies grew in all quadrants)- high salt

tolerance__

Mannitol fermentation: _ positive- bright yellow color shows the ability to ferment mannitol__

Coagulase: __clotted- coagulase positive- reacted with the prothrombin in the rabbit plasma to catalyze the

precipitation of fibrin from fibrinogen causing clumps to form__

Bile esculin: _ N/A_______________________________________________

Bacitracin sensitivity: Results:______ N/A_____ Zone size (in mm) Observed: ______ N/A_______

Optochin sensitivity: Results: ______N/A______ Zone size (in mm) Observed: ______ N/A_______

Suspected Unknown: __ Staphylococcus aureus____________________________________________