The Isolation and Detection of Non-Collagenous Proteins from the Compact Bone of the Dinosaur Iguanodon

Abstract

This report describes the isolation of guanidinium chloride extractable protein from deminer-alised bone extracts obtained from the 125–130 mya dinosaur Iguanodon. Protein products were isolated in the Mr. range 5,000–66,000 using SDS-PAGE and represent the first electro-phoretically defined proteins isolated from dinosaur tissues. The levels of glycine, aspartate and serine tentatively suggest the presence of phosphoproteins. Hydroxylysine and hydroxy-proline were not detected, confirming the presence of non-collagenous material. In addition the absence of ornithine confirmed lack of bacterial contamination. The relatively high level of leucine in the 2MNaCl NaCl fractions together with the abolition of alcian blue reactivity following protease-free chondroitinase digestion suggests the presence of proteoglycans. The study is of interest in describing the early proteins laid down in mineralised tissues for epitac-tic crystal growth and may provide evidence on evolutionary aspects of bone proteins.