ISOLATION AND PROPERTIES OF WALLS 



19 



TABLE 4 



Comparative Cell-Wall Composition for Organisms from 

 Several Microbial Groups 



% Dry Weight Cell Wall 



* Ether extractable material after HCl hydrolysis. 

 f An approximate figure. 

 References 12, 24, 29, 50. 



stances encountered in walls from the main microbial 

 groups are listed in Tables 5, 6, and 7. 



Nature seems to have utilized the polysaccharides as the 

 principle type of structural polymer. Some of these micro- 

 bial wall polysaccharides have been identified as chitin 

 [^(1 -> 4) N-acetylglucosaminide] and cellulose. That both 

 cellulose and chitin can occur together has been clearly 

 established by Fuller and Barshad.^ Both types of polysac- 

 charides were found in the cell wall of the aquatic Phyco- 

 mycete, Rhizidiomyces sp. It is now evident from studies 

 of the chemistry of cell walls that although the walls of a 



