The structure was solved by molecular-replacement methods using rabbit serum transferrin as the search model. The porcine protein crystallizes in the space group C2, with unit-cell parameters a = 223.8, b = 44.9, c = 78.9 A, beta = 105.4 degrees with one molecule in the asymmetric unit. Data for both proteins were collected using synchrotron radiation at temperatures of 277 K. The three-dimensional structures of diferric porcine and rabbit serum transferrin have been refined against X-ray diffraction data extending to 2.15 and 2.60 A, respectively.
The serum transferrins are monomeric proteins with a molecular mass of around 80 kDa and are responsible for the transport of iron in vertebrates.
