The sequence determination of a protein in a micro scale: the sequence analysis of ribosomal protein L34 of Escherichia coli

Abstract

The complete amino acid sequence of ribosomal protein L34 has been established by improved micro techniques with 3 mg of the lyophilized protein. The protein was digested with trypsin, thermolysin and chymotrypsin and the resulting peptides were isolated from fingerprints performed on cellulose thin-layer plates. The amino acid sequences of the peptides were determined by the combined micro dansyl-Edman technique using 5 - 10 nmol per sample. Aspartic acid and glutamic acid were distinguished from their amides by use of the color reaction of ninhydrin with the respective amino acid phenylthiohydantoins.