Answers are grounded in this paper and cite their sources.
The amino acid sequence of papaya proteinase IV (PPIV), a major proteinase from the latex of Carica papaya [(1989) Biochem. J. 261, 469-476] is described. The enzyme has a high degree of sequence identity with papaya proteinase III, chymopapain and papain (81, 70 and 67%, respectively), and is clearly a member of the papain superfamily of cysteine proteinases. Nevertheless, the sequence shows substitution of certain residues conserved in all other known members of the superfamily. It is suggested that some of these substitutions may account for the unusual specificity of PPIV.
No takes yet. Share an insight, caveat, or question.
Ritonja et al. (1989) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: