CRYSTALLIZATION AND PRELIMINARY-X-RAY ANALYSIS OF A FUNGAL ENDOGLUCANASE-I

An endoglucanase I (EG1) from a fungal source (Humicola insolens) has been crystallized in a number of forms suitable for X-ray diffraction analysis. Four crystal forms have been grown from various precipitants using vapour phase diffusion methods in hanging drops. Three of these crystal forms diffract to beyond 2·5 Å resolution. Two forms, obtained from ammonium sulphate at pH 5·4, or 8·0, grow as tetragonal bipyramids in space group P4122 or P4322, with approximate cell dimensions a = b = 102 A ̊, c = 282 A ̊. The other crystal forms were grown from polyethylene glycol 8000 at pH 8·0. One grows as monoclinic plates, space group P21, with cell dimensions a = 66·9 A ̊, b = 75·2 A ̊, c = 86·9 A ̊ and β = 102·9 ° and the other as long hexagonal rods in space group P6122 or P6522, with cell dimensions a = b = 119 A ̊, c = 83 A ̊. © 1992.