Organic and biochemistry  Preparation of amino acids.  Reaction of the amino acids.  Biochemical processes: Mechanism of enzyme action: chymotrypsin. 1

Preparation of amino acids: One of the most useful methods is the amination of α-halo acids. This is simply a nucleophilic substitution in which ammonia reacts with α-halo carboxylic acids. For example preparation of Alanine.

Reaction of the amino acids: Amino acids undergo reactions characteristic of both their amine and carboxylic acid functional groups, we see the acylation is a typical reaction of the amino group. We will take the reaction of Glycine with the acetic anhydride. Biochemical processes: Molecular biology: Mechanism of enzyme action. Chymotrypsin

Enzyme, we see, are protein that acts as enormously effective catalysts for biological reactions. Let us examine the action of just one: Chymotrypsin, a digestive enzyme whose job is to promote hydrolysis of certain peptide links in protein. The sequence of the 245 amino acid residues in Chymotrypsin has been determined and, through x-ray analysis the conformation of the molecule is known:

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(A) Cleavage of proton with formation of acyl enzyme and liberation of one protein fragment. (b) Hydrolysis of acyl enzyme with regeneration of the enzyme and liberation of the other protein fragment. Look at the following equation: