Accurate molecular mass determination by mass spectrometrical techniques: Differentiation of soybean lipoxygenase isoenzymes

Abstract

Molecular mass determinations for the four lipoxygenase isoenzymes from soybean seeds were compared using two mass spectrometrical (MS) techniques as well as gel permeation chromatography and sodium dodecylsulphate‐polyacrylamide gel electrophoresis. The data obtained by MS techniques were in good agreement with the molecular masses evaluated from the corresponding cDNA. The MS techniques allowed to distinguish between the lipoxygenase isoenzymes and to check the purity of enzyme preparations.