High diffraction quality crystals of cucurmosin, a type I ribosome inactivating protein isolated from the sarcocarp of Cucurbita moschata (pumpkin), have been grown under newly optimised conditions. With in-house rotating anode X-ray source, these crystals diffract to 1.65 ?resolution which is much higher than that of the previously reported crystals that diffracted only to 3 ?resolution. The crystals belong to space group P212121 with cell parameters a = 41.5, b = 58.4 and c = 99.3 . Molecular replacement studies indicate that the cucurmosin structure is homologous to trichosanthin. The initial structural model has been obtained and the model fitting/ refinement is in progress.
β-Trichosanthin,a type 1 ribosome-inactivating protein (RIP) isolated from the root tuber of Trichosanthe kirilowii Maxim,is an isoform of trichosanthin. Here we report its crystal-lization in two crystal forms using the hanging-drop vapor-diffusion method. The form A and form B crystals belong to the orthorhombic space group P212121 and monoclinic space group P21,respectively. X-ray data have been collected to 1.6 and 1.2 resolution for form A and form B crystals,respectively,using a synchrotron source.
