CRYSTALLIZATION AND PRELIMINARY CRYSTALLOGRAPHIC ANALYSIS OF 2 BETA-MANNANASE ISOFORMS FROM THERMOMONOSPORA-FUSCA KW3

Three beta-mannanase isoforms were isolated from the supernatant of a thermophilic actinomycete culture from Thermomonospora fusca KW3. Two of the isoforms (Q1, Q1.1) were crystallized by the hanging-drop metho d at room temperature using ammonium sulfate as a precipitant. The iso forms form rod-shaped colorless crystals. Both belong to the orthorhom bic space group P2(1)2(1)2(1). The cell dimensions are a = 46.7, b = 6 1.1, and c = 128.2 Angstrom for isoform Q1, and a = 43.8, b = 46.2, an d c = 132.8 Angstrom for isoform Q1.1. The asymmetric unit of either i soform contains one mannanase molecule. Native data have been collecte d to 2.2 Angstrom resolution for Q1 and to 1.65 Angstrom resolution fo r Q1.1 using synchrotron radiation.