Sequencing of peptides and proteins from the carboxy terminus

✍ Scribed by Victoria L. Boyd; MeriLisa Bozzini; Gerald Zon; Richard L. Noble; Robert J. Mattaliano

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 871 KB
• Volume: 206
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(92)90376-i

✦ Synopsis

A new chemical method for carboxy-terminal (C-terminal) protein sequencing has been developed. This approach has been successfully used to sequence 5 residues of standard proteins and 5 to 10 residues of synthetic peptides at low nanomole levels. The sequencing procedure consists of converting the C-terminal amino acid into a thiohydantoin (TH) derivative, followed by transformation of the TH into a good leaving group by alkylation. Next, the alkylated TH is cleaved mildly and efficiently with (N = C V S)- anion, which simultaneously forms a TH on the newly truncated protein or peptide. Thus, after the initial TH derivatization, there is no return to a free carboxyl group at the C-terminus. An additional benefit of this method is that the alkylating moiety can be chosen with a variety of properties allowing for variation in the detection method. This chemistry has been adapted to automated protein sequencers with a cycle time of about 1 h.