Chemical cleavage

  Cyanogen bromide

Carboxyl side of methionine residues

  O-Iodosobenzoate

Carboxyl side of tryptophan residues

  Hydroxylamine

Asparagine–glycine bonds

  2-Nitro-5-thiocyanobenzoate

Amino side of cysteine residues

Enzymatic cleavage

  Trypsin

Carboxyl side of lysine and arginine residues

  Clostripain

Carboxyl side of arginine residues

  Staphylococcal protease

Carboxyl side of aspartate and glutamate residues (glutamate only under certain conditions)

  Thrombin

Carboxyl side of arginine

  Chymotrypsin

Carboxyl side of tyrosine, tryptophan, phenylalanine, leucine, and methionine

  Carboxypeptidase A

Amino side of C-terminal amino acid (not arginine, lysine, or proline)