Functional characterization of a dockerin-containing expansin-like protein from the anaerobic fungus Neocallimastix californiae

This study reports the production and characterization of a fungal cellulosomal expansin-like protein. The corresponding NcaEXLX1 protein and truncated variant were shown to enhance the activity of an endoglucanase, similar to observations made with non-cellulosomal expansin-like proteins. Notably, the improvement in cellulase activity upon the addition of NcaEXLX1 or NcaEXLX1tr was not correlated to extent of substrate binding.