Using 1.5 mL of partially purified cell lysate, which contains 0.07 mg of total proteins (including FKBP and other proteins), the following Scatchard plot is obtained for the
binding of the protein FKBP (molecular weight 24,000 daltons) and the drug rapamycin.
What is the total mass of FKBP (sum of free and bound) in nanogram? What is the purity of lysate with respect to FKBP (total FKBP/total protein mass)? Note that in Scatchard
equation, the Ptot means total amount of protein that binds the ligand, i.e. total FKBP

 

Transcribed Image Text:

0.60 0.56 0.52 0.48 0.44 0.40 0.36 0.32 0.28 [bound rapamycin]/[free rapamycin] 0.24 0.20 0.000 0.002 0.004 0.006 0.008 0.010 0.012 0.014 0.016 0.018 0.020 [bound rapamycin] (nM) 0.60 0.56 0.52 0.48 0.44 0.40 0.36 0.32 0.28 [bound rapamycin]/[free rapamycin] 0.24 0.20 0.000 0.002 0.004 0.006 0.008 0.010 0.012 0.014 0.016 0.018 0.020 [bound rapamycin] (nM)