Preliminary joint X-ray and neutron protein crystallographic studies of endoxylanase II from the fungus Trichoderma longibrachiatum

A fungal family 11 endoxylanase has been crystallized at pH 8.5 and room-temperature X-ray and neutron diffraction data have been collected. Joint X-ray/neutron refinement is under way; the structural results will aid in rational engineering of the enzyme. Room-temperature X-ray and neutron diffraction data were measured from a family 11 endoxylanase holoenzyme (XynII) originating from the filamentous fungus Trichoderma longibrachiatum to 1.55 Å resolution using a home source and to 1.80 Å resolution using the Protein Crystallography Station at LANSCE. Crystals of XynII, which is an important enzyme for biofuel production, were grown at pH 8.5 in order to examine the effect of basic conditions on the protonation-state distribution in the active site and throughout the protein molecule and to provide insights for rational engineering of catalytically improved XynII for industrial applications