Studies in calcification The reaction of some hard- and soft-tissue collagens with 1-fluoro-2:4-dinitrobenzene

Abstract

A variety of hard and soft connective tissues of bovine and human origin were treated with fluorodinitrobenzene before, during and after treatment with demineralizing agents. Collagens of soft and demineralized hard tissues were readily distinguished from each other on the basis of the reactivity of their[epsilon] -lysyl and hydroxylysyl amino groups with fluorodinitrobenzene. In intact soft-tissue collagen only about 2/3 of these [epsilon] -amino groups reacted with fluorodinitrobenzene, but the concentration of reactive [epsilon] -amino groups of hard-tissue collagens increased from very low levels almost to the theoretical value at complete decalcification. The significance of these findings is discussed in relation to calcification in vivo.