An algorithm to analyse the hydrolysis pathway of peptides and proteins by sequence analyses of unfractionated digestion mixtures

We have designed and implemented on a personal computer a programfor identifying and quantifying the fragments present in a peptidemixture obtained by hydrolysing a polypeptide of known sequenceusing digesting agents. The qualitative data utilized by themain algorithm consist of the target sequence of the intactmolecule and the amino acid residues identified at each stepof the automatic sequence analysis of the unfractionated digestionmixture. In this way, the sequence of each fragment presentin the mixture is quickly reconstructed. Furthermore, if thequantitative data of the amino acid residues identified at eachstep of the sequence analysis are utilized, the program willcorrelate the sequence of each fragment to its amount. We furnishan example of the application intended for the rapid identificationand characterization of the extracellular proteinases producedby a basidiomycete fungus, utilizing the bovine insulin ß3-chainas target substrate. A variety of uses for the method are discussed.