Proteins — DU B. Sc. (Hons) Biochemistry Previous Year Question Papers

(b) Discuss all the constraints that effect the stability of a-helix. (c) Mention the role of following in protein chemistry: (i) Dansyl chloride (iii) High temperature (6,6,3) 5. Differentiate between the following: (i) Motifs and Domains (ii) a-helix and ?-pleated sheets (iii) Globular and Fibrous proteins (iv) Concerted and Sequential model for oxygen binding to hemoglobin (2,5,3, 5) 6. (a) Write short notes on the following: (i) Diseases due to protein misfolding Structure and function of silk fibroin (b) Write the role of the following: (ii) Cynogen bromide (iii) Trypsin 2. There are six questions. 1. (a) State whether true or false with justification : (i) Primary structure of a protein determines its function. (ii) Waving of hair is a biochemical process. (iii) Hemoglobin is a monomeric protein. (v) Peptide bond is non-planar. (vi) Protein folding is a random process. (b) Give an example of each of the following: (ii) Biologically active peptide (iii) Reagent used to break disulfide bond (iv) Membrane protein (v) Transport protein (vi) Protein chaperone (12,3) 2. (a) Explain Ramachandran Plot and its significance. Why more dihedral angles are permitted for glycine as opposed to isoleucine. (b) Discuss various forces stabilizing protein structure. (c) Explain protein sequencing by Edman degradation method. (15) 3. (a) Discuss the effect of following on oxygen binding curve of hemoglobin : (b) What is Levinthal's paradox? Describe the role of molecular chaperones in protein folding. (c) Give the significance of protein structure databases with suitable examples. (6,5,4) 4. (a) Describe all the steps required for the synthesis of Ala-Arg using Merrifield's solid phase peptide synthesis.