Question

When you use the same histone protein as your standard, you determine the histone protein concentration to be 5 mg/ml. Explain the discrepancy (pick ONE answer): (5 points) a. The histone protein has fewer basic amino acids than albumin. b. The histone protein has more acidic amino acids than albumin c. The histone protein has more basic amino acids than albumin d. The histone protein contains more methionine than albumin

Answer 1

Answer:

A. The histone protein has fewer basic amino acids than albumin

Note: The question is incomplete. The complete question is given below:

You use the Bradford (coomassie) assay to determine the concentration of a whey protein. You use bovine albumin as your standard. You determine the histone protein concentration to be 3 mg/ml. When you use the same whey protein as your standard, you determine the histone protein concentration to be 5 mg/ml. Explain the discrepancy (pick ONE answer): (2 points) The histone protein has fewer basic amino acids than albumin. The histone protein has more acidic amino acids than albumin c. The histone protein has more basic amino acids than albumin d. The histone protein contains more methionine than albumin

Explanation:

The Bradford assay measures the concentration of proteins in a a protein sample using a color change that occurs from brown to blue when the protein in the sample binds to Coomassie dye. The Coomassie dye specifically binds to basic and aromatic amino acids in the protein. A standard curve is created using absorbance data from samples of proteins of known concentrations. The spectrophotometer is set to read at 595 nm in the Bradford assay as the peak absorbance of Coomassie Blue once bound to proteins occurs at 595 nm.

The higher the concentration of proteins, the higher the color intensity and the higher the absorbance values.

Since when bovine serum albumin was used as standard, the sample protein concentration was lesser than when the protein sample was used as standard, this means that the sample protein binds less to Coomassie dye as a standard thereby giving a higher sample protein concentration than the BSA standard. Therefore, the histone protein has fewer basic amino acids than albumin.