INTERACTION OF COLLAGEN MAC ROMO L EC U L ES 



27 



predominate in some of these loci, there is a relative parity or an 

 excess of acidic groups in other regions. The analysis of the detailed 

 band pattern of SLS enables one to determine in principle, at least, 

 the packing arrangement of the TC macromolecules in any of the 

 other ordered aggregation states. 



If an acid solution of collagen is dialyzed against distilled water, 

 the final result is the production of a water-clear gel, consisting of 



^-Tij: — I 



B 



'■m 



Fig. 8. Composite micrographs illustrating the optical synthesis (b) of the 

 native-type band pattern, produced by multiple printing of the image of the 

 single segment shown in (a), stained with PTA. The recording plate was moved 

 a distance corresponding to V4 of the segment length in the axial direction 

 prior to each consecutive exposure. The summation of band densities resulting 

 from this overlap (b) corresponds closely to the band pattern of native-type 

 fibrils (c). X 250,000. (From Hodge and Schmitt, 1960.) 



