TOBACCO LEAF MESOPHYLL PEROXIDASE Isolation, Purification and Some Properties

Abstract
Two isoperoxidases (EC 1.11.1.7), P1 and P2, were isolated from tobacco (Nicotiana tabacum) mesophyll leaves by the combined methods of ammonium sulfate precipitation, polyacrylamide gel electrophoresis and DEAE-cellulose column chromatography. The pH optima for P1 and P2 were 7.0 and 7.5, respectively. The values of Km for H2O2 were 1.82 and 0.87 mM for P1 and P2. These isoperoxidases differ in their electrophoretic, catalytic and physical properties.