Unbinding of glucose from human pulmonary surfactant protein D studied by steered molecular dynamics simulations

Whole system solvated in water (rendered in MSMS) with periodic boundary conditions. The molecular model used for the SMD simulations consists of SP-D (rendered in NewCartoon) with saccharide ligands (rendered in CPK) and coordinated calcium ion (colored in green). Sodium and chloride ions are shown in yellow and pink. Virtual springs are attached to saccharides and the other end of spring links to a dummy atom to which external force is applied. The fixed atoms are colored in gray.