Articulo
Penduliflorain I: A Cysteine Protease Isolated from <i>Hohenbergia penduliflora</i> (A.Rich.) Mez (<i>Bromeliaceae</i>)
Registro en:
issn:1572-3887
issn:1573-4943
Autor
Pérez, Aurora
Carvajal, Carol
Trejo, Sebastián Alejandro
Figuerero Torres, María José
Martin, María Inés
Lorenzo, José Carlos
Natalucci, Claudia Luisa
Hernández, Martha
Institución
Resumen
Penduliflorain I, a new plant endopeptidase, was isolated and characterized from <i>Hohenbergia penduliflora</i>. Crude extract was obtained from stems. A partially purified enzyme preparation was obtained by ethanol precipitation. This preparation showed maximum activity between pH 7.5 and 8.5, was stable at ionic strength (20% decrease in proteolytic activity could be detected after 2 h in 0.4 M sodium chloride solution), and exhibited high thermal stability (inactivation required heating for 20 min at 75 °C). Inhibition and activation assays indicated the cysteine nature of the enzymatic preparation. Penduliflorain I was purified by anion exchange chromatography (Q-Sepharose HP) by FPLC system. Homogeneity was confirmed by mass spectroscopy. Molecular mass of the enzyme was 23 412.847 Da (MALDI-TOF–MS). Kinetic parameters were determined for PFLNA (Kₘ = 0.3227 mM and k<sub>cat</sub> = 4.27 s⁻¹). The N-terminal sequence (AVPQSIDWRDYGAVTTDKNQ) of isolated protease showed considerable similarity to other cysteine proteases obtained from stems or fruits of different <i>Bromeliaceae</i> species. Centro de Investigación de Proteínas Vegetales