| abstract |
A method makes it possible to determine the amino acid sequence of a polypeptide complementary to at least a part of an original peptide or protein. One aspect of the method involves: (a) determining a first nucleotide sequence of a first nucleic acid encoding the biosynthesis of at least part of the original peptide or protein; (b) determining a second nucleotide sequence of a second nucleic acid whose bases form pairs with the first nucleotide sequence of the first nucleic acid, the first and second nucleic acids forming pairs in anti-directions parallel; and (c) determining the amino acid sequence of the complementary polypeptide by the second nucleotide sequence read in the same reading frame as the first nucleotide sequence. The complementary polypeptide whose amino acid sequence is thus determined can be obtained by various means such as, for example, chemical synthesis, the derivation of a larger protein or polypeptide containing said amino acid sequence, or, when the second nucleic acid is DNA, by inserting the second nucleotide sequence into a plasmid to form a recombinant DNA plasmid vector. A unicellular organism is transformed with this vector to produce a transforming unicellular organism which biologically synthesizes said complementary polypeptide. The need to determine particular nucleotide sequences can be avoided, according to one aspect of the invention, if the relationship between amino acids having complementary hydropathies is used to make substitutions generally dictated by the complementarity between nucleotides due to forming pairs between their bases. |