In vitro bone culture technique was developed by the modification of the Goldhaber's method. Using this method, pyrophosphate was found to inhibit PTH induced bone resorption as judged by the release of previously incorporated Ca45 into the medium and by the histological findings. Furthermore, addition of pyrophosphate markedly enhanced the thyrocalcitonin inhibition of bone resorption in this ...

The technique used previously to observe complex formation between bacitracin, Mg++, and Ca5-isoprenyl pyrophosphate has been employed to measure association constants. The constant for the bacitracin A, Mg++, C55-isoprenyl pyrophosphate complex was lo6 M-I. The binding constants for other bacitracin peptides were lower and correlated with their antibiotic activities. &farnesyl pyrophosphate al...

FLEISCH, HERBERT, AND SYLVXA BISAZ. Isolation from urine of pyrophosphate, a calczjlcution inhibitor. Am. J. Physiol. 203(4) : 671-675. 1962. -The minimum value of the product, Ca x P, necessary for calcium phosphate precipitation to occur, was determined in vitro. The addition of 2.2 y0 urine to the solutions raised the mean product from 53 to 105 (mg/I oo ml)2, which shows that the urine cont...

In Escherichia coli, thiamine pyrophosphate is synthesized from thiamine monophosphate. Free thiamine is not involved as an intermediate in de novo synthesis of thiamine pyrophosphate.

Microsomes from rat liver have been shown to synthesize a squalene precursor from farnesyl pyrophosphate. This intermediate is identical with presqualene pyrophosphate, a 30-carbon cyclopropane containing pyrophosphate ester that had previously been isolated from yeast. The squalene precursor was found to be tightly, but not covalently, bound to microsomes.

Giardia lamblia is an early branching eukaryotic microorganism that derives its metabolic energy primarily from anaerobic glycolysis. In most organisms, glycolysis is catalyzed by pyruvate kinase (PK), allowing the generation of two ATP molecules from one molecule of pyruvate. Giardia has both PK and pyrophosphate-dependent pyruvate phosphate dikinase (PPDK), which catalyzes the generation of f...

To study the scintigraphic detectability of cardiac rejection, we performed 135 planar myocardial scans ([99mTc]pyrophosphate, 85; 201Tl, 36; 67Ga, 14) together with endomyocardial biopsies in ten patients for a (mean) 17-mo postoperative period. Specificity of each agent exceeded 89%. Technetium-99m pyrophosphate showed results that significantly correlated with the severity of rejection (p = ...

When pyrophosphate has been found to influence an enzymatic reaction, its action is usually indirect, that is as a chelator of free essential metal ions rather than directly on the protein catalyst. However, it appears that the latter situation holds for the action of pyrophosphate in the modification of reduced diphosphopyridine nucleotide’ to the product obtained by the action of 3-phosphogly...

We identified Alizarin Red S and other well known fluorescent dyes useful for the online detection of pyrophosphate in enzymatic assays, including the loop mediated isothermal amplification (LAMP) and polymerase chain reaction (PCR) assays. An iterative screening was used for a selected set of compounds to first secure enzyme compatibility, evaluate inorganic pyrophosphate sensitivity in the pr...

Farnesyl pyrophosphate synthetase (FPPS) synthesizes farnesyl pyrophosphate through successive condensations of isopentyl pyrophosphate with dimethylallyl pyrophosphate and geranyl pyrophosphate. Nitrogen-containing bisphosphonate drugs used to treat osteoclast-mediated bone resorption and tumor-induced hypercalcemia are potent inhibitors of the enzyme. Here we present crystal structures of sub...