Polypeptides complementary to peptides or proteins having an amino acid

Abstract

A method for determining the amino acid sequence of a polypeptide complementary to at least a portion of an original peptide or protein. In one aspect the method involves: (a) determining a first nucleotide sequence of a first nucleic acid coding for the biosynthesis of at least a portion of the original peptide or protein; (b) ascertaining a second nucleotide sequence of a second nucleic acid which base-pairs with the first nucleotide sequence of the first nucleic acid, the first and second nucleic acids pairing in antiparallel directions; and (c) determining the amino acid sequence of the complementary polypeptide by the second nucleotide sequence when read in the same reading frame as the first nucleotide sequence. The complementary polypeptide whose amino acid sequence is thus determined may be obtained by diverse means such as, for example, chemical synthesis, derivation from a protein or larger polypeptide containing said amino acid sequence, or, when the second nucleic acid is DNA, inserting the second nucleotide sequence into a plasmid to form a recombinant DNA plasmid vector and transforming a unicellular organism therewith to produce a transformant unicellular organism biosynthesizing said complementary polypeptide. The ascertainment of particular nucleotide sequences may be circumvented, in one aspect, by utilizing the relationships of amino acids having complementary hydropathies for substitutions as generally dictated by base-pairing nucleotide complementarity.