Primary Structure

STATEMENT-1 : Primary structure of proteins is determined by amino acid sequence. and STATEMENT-2 Intramolecular hydrogen bonding between carbonyl group and -overset(|)N-H group is responsible for the folding of polypeptide chain.

Proteins have primary structure. If you are given a method to know which amino acid is at either of the two termini (ends) of a protein, can you connect this information to purity or homogeneity of a protein?

A hexapeptide has the composition Ala,Gly,Phe,Val. Both the N- terminal and C- teminal units are Val. Cleavage of the hexapeptide by chymotypsin gives two different tripeptides, both having Val as the N-terminal group. Among the products of random hydrolysis is a Ala-Val dipeptide fragment . What is the primary structure of the hexapeptide?

A tetrapeptide has -COOH group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with -NH_(2) group attached to a chiral centre is :

A tetrapeptide has -COOH group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolyses. For this tetrapeptide, the number of possible sequences (primary structures) with -NH_(2) group attached to a chiral centre is

(a) Name the three major classes of carbohydrates and give an example of each of these classes. (b) Ans the following : (i) What type of linkage is responsible for the primary structure of proteins ? (ii) Name the location where position synthesis occurs in our body. OR (a) How are lipids classified ? Given an example of each class. (b) Explain the following terms : (i) Mutarotation (ii) Avitaminosis.