Ribulose bisphosphate carboxylase/oxygenase from Thiocapsa roseopersicina |
| |
Authors: | K Purohit Bruce A McFadden V Bryan Lawlis |
| |
Institution: | (1) Program in Biochemistry and Biophysics, Department of Chemistry, Washington State University, 99164 Pullman, Washington, USA |
| |
Abstract: | d-Ribulose-1,5-bisphosphate carboxylase/oxygenase has been purified 80-fold from malate-grown Thiocapsa roseopersicina by salting out the enzyme from the high-speed supernatant between 68–95% saturation with respect to (NH4)2SO4, gelfiltration through Sephadex G-100, and DEAE-cellulose chromatography followed by sedimentation into a 14–34% glycerol gradient. The specific activity of enzyme for the carboxylase reaction was 2.45 mol RuBP-dependent CO2 fixed/min · mg protein (at pH 8.0 and 30° C) and for the oxygenase reaction was 0.23 mol RuBP-dependent O2 consumed/min · mg protein (at pH 8.6, and 25° C). The enzyme, which was ultracentrifugally homogeneous in the presence of 4 and 10% v/v glycerol, was stable for at least one year at-80° C in the presence of 10% glycerol. S20, w values obtained in the presence of 4 and 10% glycerol were 19.3 and 16.2, respectively. The enzyme contained both large (53,000-daltons) and mixed small subunits (15,000- and 13,500-daltons).Borate-dependent inactivation of the enzyme by 2,3-butadione, which was greatly reduced in the presence of the product 3-phosphoglycerate, suggested that one or more arginines are at the active site.Abbreviations DTT
dithiotreitol
- RuBP
d-ribulose-1,5-bisphosphate
- SDS
sodium dodecylsulfate
- TCA
trichloroacetic acid
- TEMBDG
buffer (pH 8.0 at 25°C) containing 20 mM Tris, 1 mM disodium EDTA · 2 H2O, 10 mM MgCl2·6 H2O, 50 mM NaHCO3, 0.1 mM DTT and 10% glycerol (v/v) |
| |
Keywords: | Active site Quaternary structure Purification Ribulose bisphosphate carboxylase/oxygenase Thiocapsa roseopersicina |
本文献已被 SpringerLink 等数据库收录! |
|