Purification, crystallization and X-ray diffraction study of basic 7S globulin from soybean.

Basic 7S globulin (Bg7S) is expressed by soybeans in response to biotic or abiotic stress. Bg7S is capable of binding to a 4 kDa protein which is supposedly involved in cell proliferation. Bg7S is widely found not only in legumes, but also in other plants; however, its function is still unclear. Here, Bg7S was successfully crystallized. Orthorhombic and monoclinic crystals of Bg7S were obtained under different conditions and belonged to space groups P2(1)2(1)2, with unit-cell parameters a=111.9, b=130.1, c=287.8 Å, and P2(1), with unit-cell parameters a=85.3, b=137.6, c=162.1 Å, β=91.2°, respectively.