Spinach ribulose bisphosphate carboxylase

Spinach ribulose- bisphosphate carboxylase (rubisco) SRS Film 0.87 157.2 201.3 C222j 2.4 RRD Andersson et al (1989)... 

Case study One-dimensional disorder in spinach ribulose bisphosphate carboxylase crystals (Pickersgill 1987)... 

In spinach leaves we found a NADPH/NADP ratio of 1.8 during illumination. We conclude that this high ratio mainly reflects the NADPH/NADP in the stroma, because Dietz and Heber (l) obtained the same NADPH/NADP ratio of 1.8 for chloroplasts from illuminated spinach leaves employing nonaqueous separation of chloroplasts from frozen spinach leaves. One may argue that the ratio of NADPH/NADP contents could differ from the ratio of the corresponding free concentrations. It has been shown that NADPH can be bound to ribulose-bisphosphate carboxylase (2), but this binding was found to be substantial only in the absence of RuBP, whereas in the presence of 4 mM RuBP there was practically no binding of NADPH observed (3). Since in illuminated leaves the RuBP concentration is about 8 mM, it is not to be expected that under these conditions the ratio of free NADPH/NADP will be dramatically different from the ratio of contents. It can be therefore concluded that in illuminated leaves the NADPH/NADP ratio in the stroma is in the order of 1. 

Knight, S., Andersson, I., Branden, C.-I. Crystallographic analysis of ribulose-l,5-bisphosphate carboxylase from spinach at 2.4 A resolution. Subunit interactions and active site. /. Mol. Biol. 215 113-160,... 

STRUCTURAL INVESTIGATIONS OF D-RIBULOSE 1,5-BISPHOSPHATE CARBOXYLASE/OXYGENASE FROM ZEA MAYS AND SPINACH Joaghim Vater, Lifen Ren, Johann Salnikow, Peter M. Abuja S and Ingrid Pilz ... 

Chloroplast fructose-1.6-bisphosphatase (FBPase) is one of the 13 enzymes of the Benson-Calvin cycle, all of them so far considered as solubles in the stromal space. However, the existence of some interactions with the thylakoid membranes has been reported in the last years concerning ribulose-1.5-bisphosphate carboxylase (1), FBPase (2,3), P-ribulokinase (4), and some other. In this context Kow and Gibbs (5) have obtained under mild conditions particulate preparations from spinach chloroplasts with low, but conclusive, CO assimilation capability without addition of any soluble stromal enzyme. On the other hand, loose association between some enzymes of the Benson-Calvin cycle has been also described (6). 

Structural Investigations of D-Ribulose 1,5-Bisphosphate Carboxylase/Oxygenase from Zea Mays and Spinach 373... 

Bromo-l, 4-dihydroxy-2-butanone 1,4-bisphosphate (Br-butanone-P2), a reactive structural analog of ribulose 1,5-bisphosphate, inactivates the carboxylase by the preferential alkylation of two lysyl residues. Although functionality of these residues in binding or catalysis is not proved by these studies, all available data are consistent with their presence at the binding site for ribulosebisphosphate. The synthesis of this reagent and its use as an affinity label for the spinach carboxylase are described. 

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