Profiles of ILY, VLY and Sm-hPAF interaction with human CD59.

ABSTRACT

BACKGROUND: The molecular features of a new member of the bacterially -derived cytolysin family were examined. In particular, the interactive mechanisms of intermedilysin (ILY), vaginolysin (VLY), and Streptococcus mitis-derived human platelet aggregation factor (Sm-hPAF) with human CD59 (hCD59) were analyzed. MATERIALS AND METHODS: Molecular models of VLY and Sm-hPAF were constructed based on X-ray data of ILY (protein data bank ID=1S3R), and their interactive profiles with hCD59 were examined using molecular simulation. RESULTS: Non-binding (NB) energy between ILY and hCD59 was three orders of magnitude higher than the energy between VLY and hCD59. NB energy between Sm-hPAF and hCD59 was similar to that between VLY and hCD59. CONCLUSION: A hydrogen bond (ILY Arg432-hCD59 Glu76) was observed between ILY and hCD59, and a stronger interaction was formed by flexible adjustment between them.