4. A potential mutant bacterial alkaline phosphatase for you to purify is R166A. Briefly state what "R166A" mean (approximately one sentence or less). Make sure to include what each of the following mean in your response: "R Rn,"166", and " A". Bonus (1 point): Johnny Walker purified protein using a similar procedure that you will use. Assuming that no protein was lost during the purification (Johnny Walker is that good), what is the estimated concentration of bacterial alkaline phosphatase in the cell lysate for the following purification scenario? (in mg/mLorg/mL ) After lysing his cells with B-PER reagent, Johnny Walker tilitited his 1.0mL of cell lysate with 9.0mL of MBP purification buffer. All of this solution was used for column chromatography. From the column chromatography, Johnny eluted the protein from the column using 3mL of elution buffer. Johnny later determined the concentration of protein in his elution to be 785mg/mL