UNIT 11.5 Chemical Cleavage of Proteins on Membranes

  1. Dan L. Crimmins1,
  2. Sheenah M. Mische2,
  3. Nancy D. Denslow3

Published Online: 1 MAY 2001

DOI: 10.1002/0471140864.ps1105s19

Current Protocols in Protein Science

Current Protocols in Protein Science

How to Cite

Crimmins, D. L., Mische, S. M. and Denslow, N. D. 2001. Chemical Cleavage of Proteins on Membranes. Current Protocols in Protein Science. 19:11.5:11.5.1–11.5.13.

Author Information

  1. 1

    Washington University School of Medicine, St. Louis, Missouri

  2. 2

    Boehringer Ingelheim Pharmaceuticals, Ridgefield, Connecticut

  3. 3

    University of Florida, Gainesville, Florida

Publication History

  1. Published Online: 1 MAY 2001
  2. Published Print: MAR 2000


Described in this unit are five basic protocols that are widely used for specific and efficient chemical cleavage of proteins bound to membranes. Cyanogen bromide (CNBr) cleaves at methionine (Met) residues; BNPS-skatole cleaves at tryptophan (Trp) residues; formic acid cleaves at aspartic acid-proline (Asp-Pro) peptide bonds; hydroxylamine cleaves at asparagine-glycine (Asn-Gly) peptide bonds, and 2-nitro-5-thiocyanobenzoic acid (NTCB) cleaves at cysteine (Cys) residues. Because the above loci are at relatively low abundance in most proteins, digestion with these agents will yield relatively long peptides. In addition, an Alternate Protocol describes CNBr cleavage of PVDF-bound protein previously analyzed by Edman degradation. Finally, a Support Protocol discusses preferred methods of separating and analyzing peptide fragments generated by the chemical cleavage reactions described in the basic protocols.