Phosphoenol pyruvate carboxylase

An intriguing stress-induced alteration in gene expression occurs in a succulent plant, Mesembryanthemum crystallinum, which switches its primary photosynthetic CO2 fixation pathway from C3 type to CAM (Crassulacean acid metabolism) type upon salt or drought stress (Winter, 1974 Chapter 8). Ostrem et al. (1987) have shown that the pathway switching involves an increase in the level of mRNA encoding phosphoenol-pyruvate carboxylase, a key enzyme in CAM photosynthesis. 

J. F. Johnson, C. P. Vance, and D. L. Allan, Phosphorus deficiency in Lupinus aUms altered lateral root development and enhanced expression of phosphoenol-pyruvate carboxylase. Plant Physiol. 112 31 (1996). 

Figure 10 A hypothetical model of carbon acquisition in the marine diatom Thalassiosira weissflogii. Solid circles represent transporters. Catalyzing enzymes CA, carbonic anhydrase PEPC, phosphoenol pyruvate carboxylase PEPCK phospoenol pyruvate carboxykinase RUBISCO, Ribulose 1-5 bisphosphate Carboxylase Oxygenase (after...

Din, G.A., Suzuki, I. and Lees, H., 1967. Carbon dioxide fixation and phosphoenol-pyruvate carboxylase in Ferrobacillus ferrooxidans. Can. J. Microbiol., 13 1413— 1420. 

BRs increase C02 fixation (an indication of cytoplasmic malate synthesis via phosphoenol pyruvate carboxylase, PEP carboxylase this activity results in the accumulation of fraction-1 protein) and also in vivo C02 fixation by ribulose biphosphate action... 

Phosphonoacetic acid, a nonlabile, putative analogue of carboxyphosphate, is a potent inhibitor of sheep kidney pyruvate carboxylase. It is also a fair inhibitor of phosphoenol pyruvate carboxylase. In reply, it should be noted that phosphonoacetic acid and its derivatives are biologically active in many systems the rationale for this activity is often elusive, but probably dependent on the ability of these compounds to act as analogues of a number of diphosphate-containing biomolecules. 

Sano, K., Ito, K., Miwa, K., and Nakamori, S, (1987) Amplification of the phosphoenol pyruvate carboxylase gene of Brevibacterium lactofermentum to improve amino acid production. Agric. Biol Chem., 51 (2), 597-599. 

Wilkins,M.B. (ed.), pp. 647-671. London McGraw-Hill 1969 Wilkinson, M.J., Smith, H. Properties of phosphoenol pyruvate carboxylase from Bryophyllum fedtschenkoi leaves and fluctuation in carboxylase activity during endogenous rhythms of carbon dioxide output. Plant Sci. Lett. 6, 319-324 (1976)... 

Oxaloacetic acid, the starter compound of both the TCA and the glyoxylate cycles is regenerated from malic acid under the action of malate dehydrogenase. In green plants, oxaloacetic acid can normally be supplied in any amount needed for operation of the cycles from phosphoenol pyruvate. Oxaloacetic acid is the initial product of CO2 fixation in C4-photosynthetic and Crassulacean acid pathways. In these pathways, oxaloacetic acid is formed by yff-carboxylation of phosphoenol pyruvate catalyzed by phosphoenol pyruvate carboxylase. 

Wang D, Li Q, Mao Y, Xing JM, Su ZG (2010) High-level succinic acid production and yield by lactose-induced expression of phosphoenol-pyruvate carboxylase in ptsG mutant Escherichia coli. Appl Microbiol Biotechnol 87 2025-2035... 

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