Curley-Joseph J, Veis A
J Dent Res. 1979 Jun;58(6):1625-33. doi: 10.1177/00220345790580061201.
The bovine dentin matrix still contains some noncollagenous proteins after thorough extraction and decalcification. These have been obtained following digestion of the matrix by cyanogen bromide. Peptides containing non-collagenous portions were isolated by chromatography on diethylaminoethyl cellulose columns and fractionated on hydroxyapatite columns. Several fractions were obtained. The principal component was a complex between a highly-phosphorylated serine-aspartic acid-rich protein and a collagen peptide. These collagenous and non-collagenous moieties could not be separated from each other even under highly dissociative solvent conditions. After digestion with collagenase, the resulting phosphoprotein fraction still contained a few residues of hydroxyproline and hydroxylysine, and an enhanced content of proline, compared to the equivalent directly extractable phosphophoryn of the matrix. These data were interpreted as indicating that the phosphophoryn which is not extractable in 0.5M ethylenediaminetetraacetic acid is in fact covalently bound to some specific section of the matrix collagen. The covalent modification of the collagen matrix with highly acidic phosphoproteins may have an important role in the mineralization process.
经过彻底提取和脱钙后，牛牙本质基质仍含有一些非胶原蛋白。这些非胶原蛋白是在通过溴化氰消化基质后获得的。含有非胶原部分的肽通过在二乙氨基乙基纤维素柱上进行色谱分离，并在羟基磷灰石柱上进行分级分离。得到了几个级分。主要成分是一种富含高磷酸化丝氨酸 - 天冬氨酸的蛋白质与一种胶原肽之间的复合物。即使在高度解离的溶剂条件下，这些胶原部分和非胶原部分也无法彼此分离。用胶原酶消化后，所得的磷蛋白级分与基质中直接可提取的等效磷蛋白相比，仍含有一些羟脯氨酸和羟赖氨酸残基，且脯氨酸含量增加。这些数据被解释为表明在0.5M乙二胺四乙酸中不可提取的磷蛋白实际上与基质胶原的某些特定部分共价结合。高度酸性的磷蛋白对胶原基质的共价修饰可能在矿化过程中起重要作用。
