Effect of Surface Properties of Proteins on the Growth Rate of Subtilisin Crystals

摘要

The effect of surface properties of proteins on the growth rate of subtilisin crystals was investigated. Three subtilisin BL mutants, Properase~(TM), Purafect~(TM) and Ggm222s~(TM), were used to display the changes of surface properties of proteins. The orthorhombic crystal form of subtilisin BL was retained. However, the three mutants exhibited variations in growth rates of the different crystal faces, resulting in a pronounced variation in crystal morphology. A computer analysis of crystal structure was conducted to explore the reason for changes in the growth rate of subtilisin crystals. Three unique contact patches were located for each protein molecule. The average hydrophobicity, solvent accessible surface area (ASA) and the number of hydrogen bonds were calculated to quantify surface properties of proteins. A comparison of surface properties of proteins showed the change of morphology could not be explained solely by the currently quantified surface properties. Energetic calculations using the full structural details of proteins are considered.