X-ray grade crystals of the enzymatic fragment of diphtheria toxin.

摘要: The enzymatic fragment of diphtheria toxin, A (Mr = 21,167), complexed to the dinucleotide adenosine 3',5'-uridine (ApU), has been crystallized at two different values pH by hanging drop vapor diffusion. Crystals grown a value 5.0 (from I) belong orthorhombic space group P2(1)2(1)2(1), with unit cell parameters 71.2 A, b 73.0 c 139.8 and four protomers in asymmetric unit. 8.1 (form II) monoclinic C2, 65.2 85.6 34.6 beta 103.0 degrees one protomer Both crystal forms diffract 2.5 resolution. molecular structures obtained from these may illuminate pH-dependent transition toxin during membrane translocation.