3.1.1.27 ? x * 31000, SDS-PAGE -, 706980 3.1.1.27 dimer 2 * 28000, SDS-PAGE 80780 3.1.1.27 dimer 2 * 31000, SDS-PAGE, 2 * 29855, calculated 664212 3.1.1.27 homodimer x-ray crystallography 728919 3.1.1.27 additional information N-terminal amino acid sequence 664212