Phospholipid-Papain Interactions

Abstract

Interaction of six synthetic phospholipids with papain was studied by differential scanning calorimetry. Papain and phospholipid influenced mutually each other's main transition temperature, the enthalpy of main transition and the half with of the transition suggesting the existence of papain—hospholipid interactions. Multivariate methods proved that the length of apolar fatty acid chains of phospholipids is responsible for the effect, indicating hydrophobic interaction between papain and phospholipids. The efficacy of phospholipids increases with growing length of fatty acid chain, the grade of methylation of polar head group of phospholipids influences to a lesser extent the interaction. The presence of phospholipids has a negligible effect on the proteolytic activity of papain.