Gel filtration chromatography Affinity chromatography Which technique has allowed the purification of proteins of very low natural abundance? Which technique does NOT separate proteins on the basis of size? Dansyl chloride is used for: Endopeptidase V8 is used for: 2-Mercaptoethanol is used for: Chymotrypsin is used for: Identify the most conservative amino acid substitution, assuming that these two residues occur at the same position in two homologous proteins

1. Gel filtration chromatography

separation on the basis of size and shape

2. Affinity chromatography

separation on the basis of binding specificity

3. Which technique has allowed the purification of proteins of very low natural abundance?

molecular cloning

4. Which technique does NOT separate proteins on the basis of size?

ion-exchange chromatography

5. Dansyl chloride is used for:

amino-terminal determination.

6. Endopeptidase V8 is used for:

polypeptide cleavage on the C side of Glu

7. 2-Mercaptoethanol is used for:

reduction of disulfide bonds between cysteine residues

8. Chymotrypsin is used for:

polypeptide cleavage on the C side of Trp, Tyr, or Phe

9. Identify the most conservative amino acid substitution, assuming that these two residues occur at the same position in two homologous proteins.

Glu-->Asp

10. Structurally, myoglobin and hemoglobin are very similar proteins. In which of the following levels of structure do they differ most?

quarternary structure