Abstract
Cel7A (previously known as cellobiohydrolase I) from Hypocrea jecorina was crystallized in two crystalline forms, neither of which have been previously reported. Both forms co-crystallize under the same crystallization conditions. The first crystal form belonged to space group C2, with unit-cell parameters a=152.5, b=44.9, c=57.6 Å, β=101.2°, and diffracted X-rays to 1.5 Å resolution. The second crystal form belonged to space group P6&sub3;22, with unit-cell parameters a=b≃155, c≃138 Å, and diffracted X-rays to 2.5 Å resolution. The crystals were obtained using full-length Cel7A, which consists of a large 434-residue N-terminal catalytic domain capable of cleaving cellulose, a 27-residue flexible linker and a small 36-residue C-terminal carbohydrate-binding module (CBM). However, a preliminary analysis of the electron-density maps suggests that the linker and CBM are disordered in both crystal forms. Complete refinement and structure analysis are currently in progress.