Preliminary X-ray analysis of the binding domain of the soybean vacuolar sorting receptor complexed with a sorting determinant of a seed storage protein

beta-Conglycinin is a major seed storage protein in soybeans, which are an important source of protein. The major subunits (alpha, alpha' and beta) of beta-conglycinin are sorted to protein-storage vacuoles in seed cells. Vacuolar sorting receptor (VSR) is an integral membrane protein that recognizes the sorting determinant of vacuolar proteins, including beta-conglycinin, and regulates their sorting process. Vacuolar sorting determinants of the alpha' and beta subunits of beta-conglycinin exist in their C-terminal peptides. Here, the preliminary X-ray diffraction analysis of the binding domain of soybean VSR crystallized with the peptide responsible for the sorting determinant in beta-conglycinin is reported. X-ray diffraction data were collected to a resolution of 3.5 angstrom. The crystals belonged to space group P3(1)21, with unit-cell parameters a = b = 116.4, c = 86.1 angstrom.