biology

You are 
given 
a mixed culture of 3 bacteria
–
Methicillin
–
resistant 
Staphylococcus 
aureus
(MRSA)
, 
Escherichia coli 
and 
Enterobacter aerogenes
. Assume that 
Escherichia coli can 
ferment glucose, 
maltose, 
sucrose and lactose and also produce 
carbon dioxide gas on fermenting these. Assume that 
Enterobacter aerogenes
can 
ferment only sucrose and ca
nnot ferment glucose
, maltose
and lactose. Also on 
fermenting sucrose it produces hydrogen sulphide gas. 
Assume that 
MRSA 
does not 
ferment any of these 4 sugars
but forms endospores
and is sensitive to penicillin
. 
Also 
they all give similar looking white
–
c
olored colonies
on an agar plate
. 
Question
:
Generate 
pure cultures of these 3 bacteria using the following tools that you 
learned in the lab. 
Use any 
(some or all)
of these tools
to generate pure cultures as 
well as confirm them. 
A
) 
Any of 
Staining 
methods
B
) Special media plates
(
McConkey Agar or Blood Agar or 
Mannitol Agar plates)
C
) 
Fermentation media tubes
(
Triple Sugar Iron (TSI)
or Durham tubes)
D
) 
Any of the disc diffusion test
Assume for your answers the u
se of Agar plates or burners or boiling water bath 
allowed 
and 
any reagent can be supplied
.
Points 
included 
for 
correctly writing
the names of bacteria using the rules of 
nomenclature.