5-Phosphomevalonate

In plants, terpenes (see Chapter 6 Focus On) are biosynthesized by a pathway that involves loss of CO2 from 3-phosphomevalonate 5-diphosphate to yield isopentenyl diphosphate. Use curved arrows to show the mechanism of this reaction. 

Step 4 of Figure 27.7 Phosphorylation and Decarboxylation Three addition reactions are needed to convert mevalonate to isopentenyl diphosphate. Th first two are straightforward phosphorylations that occur by nucleophilic sul stitution reactions on the terminal phosphorus of ATP. Mevalonate is first cor verted to mevalonate 5-phosphate (phosphomevalonate) by reaction wit ATP in a process catalyzed by mevalonate kinase. Mevalonate 5-phosphat then reacts with a second ATP to give mevalonate 5-diphosphate (diphosphc mevalonate). The third reaction results in phosphorylation of the tertiar hydroxyi group, followed by decarboxylation and loss of phosphate ion. 

TSAY, Y.H., ROBINSON, G.W., Cloning and characterization of ERG8, an essential gene of Saccharomyces cerevisiae that encodes phosphomevalonate kinase, Mol. Cell. Biol., 1991,11,620-631. 

This enzyme [EC 2.T.4.2] catalyzes the reaction of ATP with (R)-5-phosphomevalonate to produce ADP and (R) -5 -diphosphome valona te. 

PHOSPHOFRUCTOKINASE 3-PHOSPHOGLYCERATE KINASE 5-PHOSPHOMEVALONATE KINASE PHOSPHORYLASE KINASE POLYNUCLEOTIDE 5 -HYDROXYL KINASE... 

R)-5-Diphosphomevalonate, formation of, 5-PHOSPHOMEVALONATE KLNASE DIPHOSPHOMEVALONATE DECARBOXYLASE... 

PHOSPHOLIPASE A2 PHOSPHOLIPASE B PHOSPHOLIPASE C PHOSPHOLIPASE D PHOSPHOLIPID FLIP-FLOP PHOSPHOMANNOMUTASE (R)-5-Phosphomevalonate, as substrate, 5-PHOSPHOMEVALONATE KINASE 5-PHOSPHOMEVALONATE KINASE... 

Eyzaguirre, J. Bazaes, S. Phosphomevalonate kinase from pig liver. Methods EnzymoL, 110, 78-85 (1985)... 

Skilleter, D.N. Kekwick, R.G.O. The enzymes forming isopentenyl pyrophosphate from 5-phosphomevalonate (mevalonate 5-phosphate) in the latex of Hevea brasiliensis. Biochem. J., 124, 407-417 (1971)... 

Bazaes, S. Beytia, E. Jabalquinto, A.M. Solis de Ovando, E Gomez, I. Pig liver phosphomevalonate kinase. 2. Participation of cysteinyl and lysyl groups in catalysis. Biochemistry, 19, 2305-2310 (1980)... 

Schulte, A.E. Van der Heijden, R. Verpoorte, R. Purification and characterization of phosphomevalonate kinase from Catharanthus roseus. Phytochemistry, 52, 975-983 (1999)... 

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