Structure of the D‐Mannan and D‐Arabino‐D‐Galactan in Crithidia fasciculata: Changes in Proportion with Age of Culture*

Abstract
Cells of the insect flagellate C. fasciculata contained mannan and arabinogalactan components whose proportion varied with culture age, with the former predominating during early stages and the latter during the later stages of exponential growth and the deceleration phase. The mannan was a .beta.-D-(1 .fwdarw. 2)-linked D-mannopyranan as shown by NMR. The arabinogalactan had a complex structure containing, in part, a .beta.-D-(1 .fwdarw. 3)-linked galactopyranose main-chain substituted in the 2 positions by single-unit D-arabinopyranose side-chains and with some unsubstituted units.