CRYSTALLIZATION OF MICROSOMAL TRIGLYCERIDE TRANSFER PROTEIN FROM BOVINE LIVER

The microsomal triglyceride transfer protein (MTP) is a heterodimeric lipid transfer protein required for the assembly of plasma very low de nsity lipoproteins in the liver and chylomicrons in the intestine. Bov ine MTP was purified by a modification of a previously published proce dure and crystals of MTP were grown reproducibly with polyethylene gly col as a precipitant at pH 7.0. MTP crystals, which diffract to Bragg spacings of better than 3.2 Angstrom, have the symmetry of space group P2(1)2(1)2(1) with refined lattice constants of a = 88.7, b = 100.9 a nd c = 201.1 Angstrom, with one heterodimer per asymmetric unit.