FIG. 4.

Induction of nahases (N), endochitinase (E), and chitobiosidase (C) from T. atroviride by chitin or chito-oligomers as assessed by separation of enzymes using native PAGE and visualization of activity from culture filtrates. Filtrates were harvested from cultures grown in EMM containing 10 mM ammonium acetate and 3% glucose. Activity was assessed by release of methylumbelliferone by digestion of the appropriate methylumbelliferyl substrate. Lanes: 0, no chito-oligomers; 1, N-acetylglucosamine; 2, N,N^I-diacetylchitobiose; 3, N,N^IN^II-triacetylchitotriose; 4, N^I,N^II,N^III,N^IV-tetra-N-acetylchitotetraose; n, colloidal chitin. Culture filtrates (75 μl) were loaded in each lane and separated at constant voltage (4 V/cm).