Patent ID: 6013478
Filing Date: 2000-01-11
Classification: C07K,C12N,Y10S

Abstract:
A method for producing a product polypeptide, comprising the steps of:(1) culturing a host cell transformed with a replicable expression vector, the replicable expression vector comprising DNA encoding a product polypeptide operably linked to a control sequence capable of effecting expression of the product polypeptide in the host cell;wherein the DNA encoding the product polypeptide has been obtained by a method comprising the steps of:(a) separately substituting a single scanning amino acid in at least one domain of a polypeptide to form at least three corresponding substituted polypeptides, each substituted polypeptide containing one scanning amino acid, wherein the polypeptide has a known interaction with a target;(b) contacting the corresponding substituted polypeptides with the target to determine an interaction, between the target and the corresponding substituted polypeptides; and(c) comparing the difference, between the interaction of the target with the polypeptide and the interaction of the target with the corresponding substituted polypeptides as an indication of location of active amino acid residue in the polypeptide of known amino acid sequence;(d) substituting a different amino acid for the scanning amino acid in at least one of the corresponding substituted polypeptides to form modified polypeptides;(e) selecting one of the modified polypeptides as the product polypeptide and cloning DNA encoding the product polypeptide into the replicable expression vector; and(2) recovering the expressed product polypeptide.