Activity Ratios of Ribulose-1,5-Bisphosphate Carboxylase Accurately Reflect Carbamylation Ratios
نویسندگان
چکیده
منابع مشابه
Activity ratios of ribulose-1,5-bisphosphate carboxylase accurately reflect carbamylation ratios.
Activity ratios and carbamylation ratios of ribulose-1,5-bisphosphate carboxylase (RuBPCase) were determined for leaves of Phaseolus vulgaris and Spinacia oleracea exposed to a variety of partial pressures of CO(2) and O(2) and photon flux densities (PFD). It was found that activity ratios accurately predicted carbamylation ratios except in extracts from leaves held in low PFD. In particular, i...
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The rate of CO(2) fixation by ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) following addition of ribulose 1,5-bisphosphate (RuBP) to fully activated enzyme, declined with first-order kinetics, resulting in 50% loss of rubisco activity after 10 to 12 minutes. This in vitro decline in rubisco activity, termed fall-over, was prevented if purified rubisco activase protein and ATP were ...
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Purified ribulose-1,5-bisphosphate carboxylase/oxygenase in 50% saturated (NH(4))(2)SO(4) was stable when frozen as small beads in liquid nitrogen and stored at -80 C. When stored as a slurry at 4 C most of the activity was lost within four weeks. This loss was due not only to enzyme polymerization. Activity in old preparations purified from spinach leaves, but not tobacco or tomato leaves, can...
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متن کاملCrystal structure of activated ribulose-1,5-bisphosphate carboxylase complexed with its substrate, ribulose-1,5-bisphosphate.
The three-dimensional structure of the complex of ribulose-1,5-bisphosphate carboxylase from Rhodospirillum rubrum, CO2, Mg2+, and ribulose bisphosphate has been determined with x-ray crystallographic methods to 2.6-A resolution. Ribulose-1,5-bisphosphate binds across the active site with the two phosphate groups in the two phosphate binding sites of the beta/alpha barrel. The oxygen atoms of t...
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ژورنال
عنوان ژورنال: Plant Physiology
سال: 1989
ISSN: 0032-0889,1532-2548
DOI: 10.1104/pp.89.3.735