Glyceraldehyde-3-phosphate dehydrogenase from human muscle: cleavage of tryptophanyl peptides with o-iodosobenzoic acid.

The new procedure of protein fragmentation with o-iodosobenzoic acid (Mahoney & Hermodson, 1979; Biochemistry, 18, 3810-3814) was used to split three tryptophanyl peptide bonds in glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12) from human skeletal muscle. The mixture obtained was separated into four homogeneous peptides by a one-step chromatographic procedure. High specificity of the cleavage reaction was proved by the amino acid analysis and determination of the N-terminal sequence of the peptide products. Both specificity ahd high yield obtained by this procedure confirmed its utility in the establishment of the protein primary structure.