Wierzbicki A, Sikes C S, Sallis J D, Madura J D, Stevens E D, Martin K L
Department of Chemistry, University of South Alabama, Mobile 36688, USA.
Calcif Tissue Int. 1995 Apr;56(4):297-304. doi: 10.1007/BF00318050.
Binding of citrate and phosphocitrate to calcium oxalate monohydrate crystals has been studied using scanning electron microscopy (SEM) and molecular modeling. Phosphocitrate structure has been resolved using low temperature X-ray analysis and ab initio computational methods. The (-1 0 1) crystal surface of calcium oxalate monohydrate is involved in binding of citrate and phosphocitrate, as shown by SEM and molecular modeling. Citrate and phosphocitrate conformations and binding energies to (-1 0 1) faces have been obtained and compared to binding to another set of calcium-rich planes (0 1 0). Difference in inhibitory properties of these compounds has been attributed to better coordination of functional groups of phosphocitrate with calcium ions in (-1 0 1). Relevance of this study to design of new calcium oxalate monohydrate inhibitors is discussed.