Rubisco, ribulose bisphosphate carboxylase

Figure 4.8 The active site in all a/p barrels is in a pocket formed by the loop regions that connect the carboxy ends of the p strands with the adjacent a helices, as shown schematically in (a), where only two such loops are shown, (b) A view from the top of the barrel of the active site of the enzyme RuBisCo (ribulose bisphosphate carboxylase), which is involved in CO2 fixation in plants. A substrate analog (red) binds across the barrel with the two phosphate groups, PI and P2, on opposite sides of the pocket. A number of charged side chains (blue) from different loops as welt as a Mg ion (yellow) form the substrate-binding site and provide catalytic groups. The structure of this 500 kD enzyme was determined to 2.4 A resolution in the laboratory of Carl Branden, in Uppsala, Sweden. (Adapted from an original drawing provided by Bo Furugren.)...

The virtual SWISS-PROT entries have a far-reaching effect on TrEMBL. For example, the virtual entry for the Rubisco (ribulose-bisphosphate carboxylase) large chain affects 3300 TrEMBL entries. Therefore a system has been developed to decompose these virtual entries into rules that are stored in a relational database with proper version control features. 

Rubisco (ribulose bisphosphate carboxylase-oxygenase) The enzyme that accomplishes carbon fixation in photosynthesis by adding CO2 to ribulose-1,5-bisphosphate. It can also add O2 in place of CO2, initiating photorespiration. 

Rubisco (Ribulose Bisphosphate Carboxylase-Oxygenase) The enzyme that accomplishes carbon... 

In this reaction, one molecule of ribulose-1,5-bisphosphate (metabolite 1) and one molecule of CO2 (metabolite 2) give rise to two molecules of 3-phosphoglycerate (metabolite 3). The enzyme responsible has the EC number 4.1.1.39. The annotated enzyme list shows that this refers to ribulose bisphosphate carboxylase ( rubisco for short). Rubisco belongs to enzyme class 4 (the lyases) and, within that group, to subclass 4.1 (the car-boxy-lyases). It contains copper as a cofactor ([Cu]). 

Why is ribulose bisphosphate carboxylase (RUBISCO) a poor target for a herbicide ... 

The enzyme responsible for the fixation of CO2, ribulose bisphosphate carboxylase/oxygenase (RUBISCO), also catalyses the oxygenation of ribulose bisphosphate to form one molecule of phosphoglycerate and one molecule of phosphoglycolate. Under normal C02 and 02 concentrations six ribulose bisphosphate molecules react with oxygen for every 15 that react with carbon dioxide. 

Ribothymidylic acid residue 813 Ribozyme(s) 649 - 652, 239 artificial 652 hairpin 649,651s hammerhead 649, 651 leadzyme, 651s Ribulose 164s Ribulose bisphosphate 707s Ribulose bisphosphate carboxylase (Rubisco)... 

The key reaction of the Calvin-Benson cycle of C02 reduction is the carboxylation of ribulose bisphos-phate to form two molecules of 3-phosphoglycerate (Eq. 13-48). The properties of ribulose bisphosphate carboxylase (rubisco, Figs. 13-10 to 13-12), which catalyzes this reaction, are discussed in Chapter 13. It... 

The dark reactions (carbon-fixation reactions) use the ATP and NADPH produced by the light reactions to fix carbon dioxide as carbohydrate sucrose and starch. The reactions form a cycle (the Calvin cycle) in which the enzyme ribulose bisphosphate carboxylase (rubisco), located in the stroma, condenses a C02 molecule with ribulose 1,5-bisphosphate to produce two molecules of 3-phosphoglycerate. Other reactions then regenerate the ribulose... 

This pathway is sometimes called the Calvin-Benson cycle, after the biochemists who elucidated it. The 5-carbon, doubly phosphorylated carbohydrate, ribulose bisphosphate is the acceptor for CO2 the enzyme is called ribulose-bisphosphate carboxylase/oxygenase (called Rubisco). 

The first stable product of carbon fixation by the enzyme, ribulose bisphosphate carboxylase (Rubisco), is glyceraldehyde 3-phosphate, a 3-C sugar. This 3-C sugar is fed into biosynthetic pathways and forms the basis for all organic compounds produced by photosynthetic organisms. Fixed carbon and major and trace elements... 

The reaction is catalyzed by ribulose bisphosphate carboxylase, "Rubisco", which is probably the most abundant enzyme on earth (it is 10-25% of leaf protein). 

Starch and sucrose, key substrates for the development of dental caries, are exclusively synthesized by plants. They are made in plant leaves by a process called photosynthesis, which utilizes sunlight as the energy source. This chapter outlines the light and dark reactions of photosynthesis and compares the light reaction with mitochondrial electron transport (Sect. 1). The key dark reaction, the production of phosphoglycerate by the enzyme ribulose bisphosphate carboxylase (rubisco), is described along with the production of fructose, sucrose, and starch (Sect. 2). The chapter concludes with a detailed discussion of the roles of starch and sucrose in plant metabolism (Sect. 3). 

The term "molecular chaperone" is not novel and was first introduced (7) to describe the transient association of nucleoplasmin with the histones during the formation of nucleosomes. Subsequently, a similar transient association was found in the chloroplast of higher plants between nascent Large subunits (LSU) of die enzyme Ribulose bisphosphate carboxylase (Rubisco) and a SdOkDa protein complex composed of 12-14 60kDa subunits (2). The nascent chloroplast-synthesized LSU was found to bind this complex in a non-covalent manner and in sub-stoichiometric amounts. 

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

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