title: Comparison of two cysteine endopeptidases from Pseudananas macrodontes (Morr.) Harms (Bromeliaceae).
abstract: 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.
authors.affiliation: LIPROVE, Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Argentina.
authors.forename: L M
authors.initials: LM
authors.lastname: López
authors.forename: C
authors.initials: C
authors.lastname: Sequeiros
authors.forename: S A
authors.initials: SA
authors.lastname: Trejo
authors.forename: M F
authors.initials: MF
authors.lastname: Pardo
authors.forename: N O
authors.initials: NO
authors.lastname: Caffini
authors.forename: C L
authors.initials: CL
authors.lastname: Natalucci
mesh_terms: D000595:Amino Acid Sequence; D003546:Cysteine Endopeptidases / Q000737:chemistry* / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D015180:Electrophoresis, Gel, Two-Dimensional; D005638:Fruit / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D015853:Cysteine Proteinase Inhibitors; D010940:Plant Proteins; D003546:Cysteine Endopeptidases; C449003:macrodontain II protein, Pseudananas macrodontes; C407302:macrodontain-I protein, Pseudananas macrodontes