Comparison of two cysteine endopeptidases from Pseudananas macrodontes (Morr.) Harms (Bromeliaceae).

LÓPEZ LMI; SEQUEIROS C; TREJO SA; CAFFINI NO; NATALUCCI CL

BIOLOGICAL CHEMISTRY

WALTER DE GRUYTER & CO

Lugar: Berlin; Año: 2001 vol. 382 p. 875 - 878

1431-6730

The properties of two cysteine peptidases (macrodontain I and II) isolated from fruits of Pseudananas macrodontes have been compared. The enzymes showed optimum pH ranges near neutrality and were inhibited by E-64 and other cysteine peptidase inhibitors. Molecular masses were 23459 and 23703 kDa, the isoelectric points were 6.1 and 5.9, and the Km values were 13.4 and 8.9 microM (Bz-Phe-Val-Arg-AMC) for macrodontain I and II, respectively. N-alpha-CBZ-L-amino acid p-nitrophenyl esters were tested for both enzymes. The N-terminal sequences of both proteases differed slightly and showed high sequence similarity to other pineapple stem-derived cysteine endopeptidases.