Protein Microsequence Analysis with Dansylamino-PITC

In addition to PITC introduced first for the sequential degradation of proteins and peptides by Edman (1949), several other Edman-type coupling reagents for N-terminal sequencing have been synthesized as reviewed by Doolittle (1982). However, the use of most of these reagents is associated with some limitations for sequence analysis. For example, some of them carry a bulky side group which often sterically hinders the reactive group, resulting in a low coupling yield, and some produce a large number of reaction by-products caused by the side reactions. Such problems have restricted the use of these reagents in protein sequencing.