Purification and characterization of a C-S-lyase from ramson, the wild garlic, Allium ursinum

• Published in: Planta medica Vol. 60; no. 4; p. 343
• Main Authors: Landshuter, J, Lohmueller, E.M, Knobloch, K. (Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Botanik und Pharmazeutische Biologie)
• Format: Journal Article
• Language: English
• Published: Germany 01.08.1994
• Subjects: ALLIUM; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; LIASAS; LYASE; PURIFICACION; PURIFICATION
• ISSN: 0032-0943; 1439-0221
• DOI: 10.1055/s-2006-959497

A C-S-lyase preparation from ramson, Allium ursinum L, has been purified to apparent homogeneity. Separation techniques applied were hydrophobic interaction chromatography, anion exchange chromatography, and gel permeation chromatography. A 52-fold purification was obtained. The enzyme could be characterized by a molecular mass of M=150000 with subunits of 50000. Its isoelectric point was determined to be at 4.7. The pH-optimum for the substrate-dependent turnover was found at 6.0. The temperature optimum was at 35 degrees C. (+)-Alliin as the substrate caused the highest enzymatic reaction velocity. The lowest Km value was observed with (+)-S-propyl-L-cysteine sulfoxide. Inhibitor constants were elaborated for the deoxy-derivatives of the substrates inserted and, likewise, for related amino acids. The protein was sensitive to low concentrations of hydroxylamine, indicating pyridoxal phosphate as a cofactor. Activation energies were determined for the cleavage of alliin, S-propyl-L-cysteine sulfoxide and S-methyl-L-cysteine sulfoxide, and were found to be in the range of 9 to 13 kJ mol-1.