4.1.1.11 tetramer crystallographic data. Tetramer with pseudofour-fold rotational symmetry. The subunits are six-stranded beta-barrels capped by small alpha-helices at each end. The active sites are located between adjacent subunits 3949 4.1.1.11 tetramer x * 2800, beta, + x * 11000, alpha, + x * 13800, pi, SDS-PAGE, enzyme comprises principally the unprocessed pi-subunit, with a small proportion of the alpha-subunit and the beta-subunit. The enzyme is synthesized initially as an inactive proenzyme, the pi-protein, which is proteolytically cleaved at a specific X-Ser bond to produce a beta-subunit with XOH at its C-terminus and an alpha-subunit with a pyruvoyl group at its N-terminus, derived from serine 3950 4.1.1.11 ? x * 14100, pi-protein, calculated from the amino acid sequence 649350 4.1.1.11 tetramer active enzyme is a tetramer composed of three alpha- and beta-subunits and an incompletely processed pi-protein -, 649350 4.1.1.11 tetramer 4 * 14000 650836 4.1.1.11 homotetramer 4 * 14000, about, native pi-protein, secondary structure, SDS-PAGE 650998 4.1.1.11 tetramer 4 * 16000, recombinant enzyme, inactive pi-proenzyme, which is cleaved into the 13.22 kDa alpha-subunit and 2.74 kDa beta-subunit, processing is not essential for tetramer formation, SDS-PAGE -, 653749 4.1.1.11 ? x * 58000, SDS-PAGE 665041 4.1.1.11 ? x * 13800, SDS-PAGE 682386 4.1.1.11 octamer two tetramers forming a pseudo fourfold rotational symmetry, the enzyme protein shows a double-psi beta-barrel structure 682753