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DISCUSSION 



K. E. Van Holde, M. J. Glimcher, J. W. Green, S. B. Barker, 

 L. V. Beck, C. L. Prosser, A. G, Richards 



Dr. Van Holde (University of Illinois): Have you studied the binding of 

 phosphate ion by collagen fibrils or by soluble collagen? 



Dr. Glimcher: We are currentlv studving the binding of both calcium and 

 phosphorus by collagen macromolecules in solution and bv the "solid" collagen 

 fibrils i^i small decalcified bone particles and plan to repeat the studies using 

 purified reconstituted collagens as well as collagen in solution. In these studies 

 we have encountered several difficult technical problems, as well as some 

 interesting phenomena which are difficult to interpret. In the first place, only 



