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.
