Exam 27: Amino Acids and Proteins

Why do amide bonds exist as reasonably stable s-cis or s-trans isomers at room temperature?

Why is the s-trans form of an amide bond more stable?

What is the name given to the pH at which the concentration of the zwitterionic form of an amino acid is at a maximum concentration?

What is the major organic product for the following reaction?

What is the separation of a racemic mixture into its component enantiomers called?

Reaction of a polypeptide,composed of 12 amino acids,with carboxypeptidase A releases Met (C-terminal amino acid).The polypeptide undergoes partial hydrolysis to give 12 groups of peptides.Use the groups of overlapping amino acids to determine the proper sequence of this polypeptide.Note: Since these lists of peptides are separated by commas,they are not necessarily in the proper sequence. Ser,Lys,Trp-5.Met,Ala,Gly- 9.Lys,Ser Gly,His,Ala-6.Ser,Lys,Val -10.Glu,His,Val Glu,Val,Ser-7.Glu,His-11.Trp,Leu,Glu Leu,Glu,Ser-8.Leu,Lys,Trp-12.Ala,Met