Calcium- and hydroxyapatite-binding properties of glucuronic acid-rich and iduronic acid-rich glycosaminoglycans and proteoglycans.
This study describes the interaction of a small chondroitin sulphate proteoglycan and the glycosaminoglycans chondroitin 4-sulphate, dermatan sulphate and heparan sulphate with hydroxyapatite. All macromolecules possessed a high affinity, with the iduronic acid-rich dermatan sulphate and heparan sulphate displaying higher adsorption maxima than the glucuronic acid-rich chondroitin 4-sulphate. At similar concentrations, dermatan sulphate produced a 30% inhibition of hydroxyapatite-induced crystal growth, whilst chondroitin 4-sulphate yielded 50% inhibition. Estimation of the calcium binding capacity of these glycosaminoglycans using equilibrium dialysis indicated that chondroitin 4-sulphate bound five times more calcium than dermatan sulphate at a calcium concentration similar to that of serum. The data indicate a possible important role for chondroitin 4-sulphate in dentinogenesis where it is the dominant glycosaminoglycan, since it could act as a capture point for calcium ions during mineralisation, with the leucine-rich domain of its parent proteoglycan acting as anchor points to type I collagen.
Embery
G
G
Department of Basic Dental Science, Dental School, University of Wales College of Medicine, Cardiff, UK. bdentsci@cardiff.ac.uk
Rees
S
S
Hall
R
R
Rose
K
K
Waddington
R
R
Shellis
P
P
D000327:Adsorption; D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000737:chemistry / Q000378:metabolism; D002809:Chondroitin Sulfates / Q000737:chemistry / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D003460:Crystallization; D003804:Dentin / Q000737:chemistry / Q000378:metabolism; D003871:Dermatan Sulfate / Q000737:chemistry / Q000378:metabolism; D017886:Durapatite / Q000737:chemistry / Q000378:metabolism; D005965:Glucuronates / Q000737:chemistry; D020723:Glucuronic Acid; D006025:Glycosaminoglycans / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007067:Iduronic Acid / Q000737:chemistry; D066298:In Vitro Techniques; D009805:Odontogenesis / Q000502:physiology; D011509:Proteoglycans / Q000737:chemistry* / Q000378:metabolism
D005965:Glucuronates; D006025:Glycosaminoglycans; D011509:Proteoglycans; D003871:Dermatan Sulfate; D007067:Iduronic Acid; D020723:Glucuronic Acid; D002809:Chondroitin Sulfates; D003094:Collagen; D017886:Durapatite; D002118:Calcium