Bacterial pyrophosphatase

FARRE, E.M., BACHMANN, A., WILLMITZER, L., TRETHEWEY, R.N., Acceleration of potato tuber sprouting by the expression of a bacterial pyrophosphatase, Nature Biotech., 2001,19,268-72. 

Fig. 6. Distribution of the most common folds in selected bacterial, archaeal, and eukaryotic proteomes. The vertical axis shows the fraction of all predicted folds in the respective proteome. Fold name abbreviations FAD/NAD, FAD/NAD(P)-binding Rossman-like domains TIM, TIM-barrel domains SAM-MTR, S-adenosylmethionine-dependent methyltransferases PK, serine-threonine protein kinases PP-Loop, ATP pyrophosphatases. mge, Mycoplasma genitalium rpr, Rickettsiaprowazekii hh x, Borrelia burgdorferi ctr, Chlamydia trachomatis hpy, Helicobacter pylori tma, Thermotoga maritima ssp, Synechocystis sp. mtu, Mycobacterium tuberculosis eco, Escherichia coli mja, Methanococcus jannaschii pho, Pyrococcus horikoshii see, Saccharomyces cerevisiae, cel, Caenorhabditis elegans.

Hydrolysis of sugar nucleotides with unspecific pyrophosphatases has already been mentioned (Section 11,1, p. 310). A similar reaction is catalyzed by a bacterial enzyme specific for adenosine 5 -(a-D-glucopyranosyl pyrophosphate).459 The specific conversion of uridine 5 -(a-D-glucopyranosyl pyrophosphate) into a-D-glucopyranosyl phosphate, uridine, and inorganic phosphate was observed with an enzyme from Escherichia colt 459,460 a preparation from Bacillus subtilis can act in a similar manner461 on different sugar nucleotides. ... 

Pyrophosphatases, which are present in all cells, and catalyze hydrolysis of inorganic pyrophosphate (PPj) to orthophosphate (P ) (see Chapter 6, Section D), also drive metabolic sequences. The very active pyrophosphatase of E. coli has a turnover number of over 2 x 104 s 1 at 37°C. The 1000 molecules per cell are sufficient to immediately hydrolyze any pyrophosphate produced by bacterial metabolism.733 The much studied soluble pyrophosphatases of E. coli,7 A 7 ,r yeast,736 and other organisms736ab are metalloenzymes that are most active with Mg2+. Two Mg2+ ions are held, mostly by carboxylate side chains, while a third apparently enters the active site as magnesium pyrophosphate, perhaps MgP20-. As with other metallohydrolases, a metal-bound hydroxyl ion may serve as the attacking nucleophile. 

Adenylate cyclase has been obtained in soluble form from bacteria [12,13], and can be prepared free of contaminating phosphodiesterase, ATPase (adenosine triphosphatase) and pyrophosphatase activities, but the relationship of the bacterial enzyme to the enzyme found in higher forms of life is not yet clear. The bacterial enzyme, for example, does not respond to mammalian hormones or sodium fluoride. 

SOME SIMILARITIES AND DIFFERENCES BETWEEN BACTERIAL CHROMATOPHORE, SPINACH CHLOROPLAST AND YEAST MITOCHONDRIAL INORGANIC PYROPHOSPHATASES... 

Some Similarities and Differences Between Bacterial Chromatophore, Spinach Chloroplast and Yeast Mitochondrial Inorganic Pyrophosphatases 197... 

Deoxycytidylate deaminase is evidently absent from a number of bacterial species, includii E. coli, S. typhimvrium, and B. subtilts. Accordingly, in these cells the deoxycytidine phosphates do not contribute to the synthesis of the thymidine phosphates in the manner described above for animal cells. However, enzymes catalyzing the deamination of dCTP have been demonstrated in E. ccU and S. typhimvrium the latter enzyme has been partly purified and shown to deaminate dCTP, but not CTP, dCDP, CDP, eytidylate, nor deoxycytidine (26). The formation of dUTP by this enzyme, followed by the action of the specific dUTP pyrophosphatase, would consitutue a route for the formation of deoxyuridylate ... 

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