214 



MACROMOLECULAR COMPLEXES 



( Kessler and Nickerson, 1959) followed the scheme of fractionation 

 shown in Fig. 4. Lipid-free cell-wall material was suspended in 1 N 

 KOH for 1 hour under nitrogen at 25° C; the solution obtained was 

 passed through an ultrafine sintered glass filter. The filtrate was 

 dialyzed for 24 hours against running tap-water and lyophilized. 

 The resulting white powder was suspended in water at 25° C for 1 

 hour, then centrifuged. The centrifugate was saturated with am- 

 monium sulfate; a precipitate was obtained that was removed bv 

 high-speed centrifugation. The precipitate and the supernatant 

 were dialyzed, concentrated, and Ivophilized. Both of the resulting 

 white powders proved to be polysaccharide-protein complexes, with 



Fig. 5. Electron micrograph of glucomannan-protein I (GMP-I). Note aggre- 

 gation of small spherical structures into globular masses. Deposited from 

 solution onto Formvar film. 



