GENERATION OF LIBRARY OF SOLUBLE RANDOM POLYPEPTIDES LINKED TO mRNA

Abstract

Methods and compositions are provided for producing libraries of soluble random polypeptides. In the methods, the fraction of hydrophilic residues in the polypeptide is controlled so as to maintain the solubility of the polypeptide constructs.

1 . (canceled) 
     
     
         2 . A library of soluble polypeptides linked to polynucleotides encoding the polypeptides, comprising:
 a plurality of polynucleotides, each of the plurality of polynucleotides comprising a plurality of codons,   wherein a proportion of hydrophilic or surface compatible amino acid residues encoded by said codons of said each of the plurality of polynucleotides satisfies the following formula:
     c ≥(8/0.41 N )̂1/3−0.05
 
   where N=the number of amino acids in said each of the plurality of polynucleotides, and c=a fraction of amino acids that are hydrophilic or surface compatible in said each of the plurality of polynucleotides; and   an encoded polypeptide linked to each of said each of the plurality of polynucleotides, wherein an amino acid sequence of the encoded polypeptide is encoded by the each of said each of the plurality of polynucleotides that is linked to the encoded polypeptide.