The structure of endoglucanase I (Trichoderma resei) in solution

The structure of endoglucanase I (EG I) from Trichoderma reesei has been investigated in solution, using small-angle x-ray scattering. The enzyme showed the typical shape (“tadpole”) and domain arrangement (catalytic core-spacer-cellulose binding domain) which is obviously common to all celluloses degrading solid substrate. The molecular size parameters resemble cellobiohydrolase I closely: radius of gyration is 4.74 nm, overall length 18.0 nm, diameter 5.3 nm. The main difference lies in the spacer region, which contains much more scattering mass, probably due to a higher extent of glycosylation which extends towards the core domain.