A modeling study of the role of proteins in calcium oxalate kidney stone formation.

摘要

Kidney stones affect about 12% of the population in developed countries. Calcium Oxalate (CaOx) usually is the most common constituent of stones. Reasons for stone formation are unknown, but it is believed that macromolecules either promote or inhibit nucleation, growth, aggregation. Various proteins have been suggested as having a role in stone formation. It has been hypothesised that acidic amino acids residues such as Aspartate (Asp), Glutamate (Glu) and Carboxyglutamic acid (Gla) bind Calcium and therefore bring about a strong interaction with mineral surfaces. In this thesis I took protein structures from Protein Data Bank (PDB) and visually examined how well they fit various surfaces of CaOx mono and dihydrate. For most macromolecules there were only 3--4 points of contact, due to the 3D shape of the protein molecule. In general small molecules have better contact than large molecules. It would appear that proteins do not interact strongly with CaOx mineral surfaces and their role in nephrolithiasis might be more indirect.