Bacillus cereus由来スフィンゴミエリナーゼのX線結晶構造解析

抄録

Degradation of cell membrane and mucosa, of which phospholipads are major components, and production of lipid mediators are roles of phospholipases from pathogenic bacteria to grow, survive and spread in the host organism. The studies on the enzymes are important for the pathobiology of bacterial infectious disease. The crystal structure of Sphingomyelinase from Bacillus cereus revealed the structure basis of the phospholipase C and hemolysis activities in a divalent cation dependent manner. The water-bridged double divalent cations were concluded to be the catalytic architecture to the phospholipase C activity. In addition, the β-hairpin structure with aromatic amino acid residues was shown to be involved in the membrane binding of the enzyme as a part of the hemolysis activity.