Preliminary Studies of the Ultracentrifugal and Free Zone Electrophoresis 275 



A D 



Fig. 3. Free zone electrophoresis patterns at various Fig. 4. Identical conditions as Fig. 3. d) pH 5.52 at 



pH's at constant ionic strength potassium phosphate 150 min., sodium acetate buffer, e) pH 5.14 at 150 min., 



bulTer of 0.1, 2,5^, protein concentration is 1.4°/o. a) sodium acetate buffer, f) pH 3.61 at 120 min., sodium 



pH 7.51 at 105 min., b) pH 6.64 at 150 min., c) pH formate buffer. A — ascending patterns, D — descend- 



6.04 at 160 min. A — ascending patterns, D — descend- ing patterns. — Arrows point in direction of move- 



ing patterns. — Arrows point in direction of move- ment. Vertical line at end of arrow is starting point 

 ment. Vertical line at end o arrow is starting point 



Conclusions 



Analysis of these and other findings have led us to the following conclusions. 



1. The major portion of the neutral soluble proteins of premolar bovine-embryo 

 enamel matrix exists in aqueous solution as a mixture of labile, reversibly equilibrat- 

 ing species, but that in addition there are minor non-interacting components present. 



2. The interacting proteins constitute either a polymerizing multi-component system 

 v/ith rapid re-equilibrating kinetics with respect to transport processes, or a poly- 

 merizing single component system whose reaction kinetics are of an intermediate type 

 and are dependent on solution conditions. 



Acknowledgements 

 This work was supported by research grants from the U. S. Public Health Service, 

 National Institutes of Health (AM-06375), and the John A. Hartford Foundation, Inc. 



18=' 



