We have decided to isolate the food vacuoles and examine
the existence of proton pumps using a variety of antibodies.
Examine the results of this experiment.
The results below were obtained
using primary antibodies against a common proton pump known to exist in
paramecium (MW 56.1 kDa):
Legend
Lanes 1, 8 Size marker (kilo Daltons)
Lane 2 Purified
proton pump
Lane 3 Lysate
of the whole Paramecium
Lane 4 Lysate
of the Parameciun food vacuole collected 0.5 min after feeding.
Lane 5 Lysate
of the Parameciun food vacuole collected 5 min after feeding.
Lane 6 Lysate
of the Parameciun food vacuole collected 10 min after feeding.
Lane 7 Lysate
of the whole Paramecium reacted only with the secondary antibody. |
 |
Why did we use a sample of the purified proton
pump (lane 2)?
Choose between right and wrong.
|
|
A. Using
the purified protein we show that no other proteins can be recognized by
our antibodies (no crossreactivity of the primary antibody with other proteins
is detected).
B. The
purified protein was used as a size reference that will indicate the size
of the proton pump.
C. The
purified protein serves to test whether the treated paramecia (exposed
to yeast- containing medium for 30 sec) expresses proton pumps, as we previously
hypothesized.
D. The
purified protein is used as a positive control - it verifies the proper
functioning of the antibodies and all other reagents.