Figure 4.

FTL1793 exhibits chitinase activity. Recombinant FTL1793 protein was expressed and purified from Escherichia coli. Chitin azure assays were used to measure chitinase activity. In these assays, 94 μg of each of the following proteins were added per reaction: recombinant FTL1793, chitinase from Streptomyces griseus (positive control), or recombinant Ft FopA protein (negative control). Chitin azure in assay buffer alone (buffer) was also tested. Reactions were incubated on an end-over-end carousel for either: (A) 48 h at 37 °C; or (B) 30 d at 37 °C. Absorbance at 570 nm was measured to determine chitin cleavage. Samples were prepared in triplicate and measurements recorded every 24 h.