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Using 99Tcm-Sn-polyphosphate, macroautoradiographs were produced of 34 standardized, medullary-nailed, 1--10-week-old tibial fractures in the rat. The radioactivity was localized in the callus and epiphyseal growth plate. On microautoradiography the 99Tcm-Sn-polyphosphate was found diffusely scattered within the mineralizing part of the callus and the epiphyseal growth plate.
During commercial processing of broiler chickens, injection of polyphosphate (Puron 604 or 6040) resulted in microorganisms being added to the deep breast muscle. The level of contamination was related to the microbiological condition of the injection solution. Injection of polyphosphate had no effect on the shelf-life of fresh chilled carcasses held at 1 degree of 10 degrees C but changes were observed in the growth rate of microorganisms in the deep muscle and in the composition of the muscle microflora following storage. Cross-contamination of carcasses and the transfer of organisms from the skin to the deep muscle during injection was demonstrated with a marker strain of Clostridium perfringens. However, both processes were influenced by the number of marker organisms applied initially to the skin. The above findings are discussed in relation to the possible behaviour of any food poisoning bacteria present.
When solutions of nucleoside 5'-phosphates and trimetaphosphate are dried out at room temperature, nucleoside 5'-polyphosphates are formed. The Mg++ ion shows a superior catalytic function in this reaction when compared with other divalent metal ions. Starting with nucleoside 5'-phosphates, Mg++ and trimetaphosphate, the predominant products in the nucleoside 5'-polyphosphate series pnN are p4N, P7N and p10N. Nucleoside 5'-diphosphates yield p5N and p8N, nucleoside 5'-triphosphates give p6N and p9N. The prebiological relevance of these reactions is discussed.
A ribosome-independent guanosine 5',3'-polyphosphate synthetase has been highly purified from Bacillus brevis (ATCC 8185). The enzyme has a molecular weight of 55,000, as measured by sucrose density gradient centrifugation. Like the ribosome-connected stringent factor of Escherichia coli, it catalyzes the synthesis of the guanosine 5', 3'-polyphosphates by a pyrophosphoryl transfer mechanism from adenosine triphosphate (ATP) to guanosine di- or triphosphates (GDP, GTP). It has an apparent Km of 0.14 mM for GDP and 0.77 mM for GTP, and is specific for the guanosine ribonucleotides as pyrophosphoryl acceptors. Several ATP analogues were tested for their ability to donate the pyrophosphoryl group. Mg2+ was required as a counter ion for the nucleotide substrate; however, an excess of Mg2+ was inhibitory. The property of the B. brevis enzyme is compared with the ribosome-linked enzyme of E. coli and an extracellular enzyme excreted by several types of Streptomyces reported upon recently.
Polyphosphate of average chain length corresponding to 10 phosphate units was detected in the mycelial extract of zygomycetes. Gel electrophoresis techniques commonly used for the separation and characterization of acidic mucopolysaccharides were successfully used for the detection, purification, and characterization of the polyphosphate.
Preexposure of hydroxyapatite (HA) to polyphosphate reduced the near-equilibrium acid solubility of HA, the mineralization of HA, and the exchange of PO4 between medium and HA. Appreciably longer exposure times were required for maximal effects of trimetaphosphate (TMP) than of pyrophosphate (PP), tripolyphosphate (TPP), and hexametaphosphate (HMP). Calcifying solution solubilized small amounts of the HA-bound polyphosphates. This occurred to the smallest extent in the case of TMP, a fact which could have relevance for the superior anticaries effect of TMP.
Labile polyphosphate phosphohydrolase from Endomyces magnusii is 27-fold purified by means of fractionation with ammonium sulphate, gel filtration on Sephadex G-75 and Biogel P-60 and chromatography on DEAE cellulose. Chromatography on DEAE Sephadex A-50, isoelelctric focusing and polyacrylamide gel electrophoresis of the enzyme preparation revealed 3 different fractions with polyphosphate phosphohydrolase activity (PPPH1, PPPH2 and PPPH3). Relative content of these fractions in E. magnusii cells is 30%, 55% and 15% respectively. Isoelectric points are: PPPH1--pH 5.1--5.2; PPPH2--pH 6.0--6.1; PPPH3--pH 6.3--6.4. PPPH1 and PPPH2 are found to be the most labile. PPPH3 is more stable under isolation procedure and storage. The fractions have similar molecular weight (48 000 +/- 3000).
An addition of exogenous adenine to an autolysing 72-hour culture of Corynebacterium sp., strain BSTI-301 results in accumulation of as much as 0,6--1,0 mp of ATP per 1 ml of medium. Extracellular ATP accumulation under such conditions is coupled with a considerable decrease of the intracellular content of 5'-phosphoribosyl-1-pyrophosphate, orthophosphate, pyrophosphate and two fractions of high-polymeric polyphosphates PPh3 and PPh4, as compared to the control. The activity of pyrophosphate phosphohydrolase (EC 3.6.1.1) and polyphosphate phosphohydrolase (EC 3.6.1.11) is thereby considerably decreased in the cells growing on exogenous adenine, while the activity of ADP-phosphotransferase (EC 2.7.4.1) is increased 2-fold. It was found that in experiments with 14C-adenine the intracellular content of both ATP and ADP remains unchanged despite a considerable accumulation of extracellular ATP in Corynebacterium sp., strain BSTI-301 cells.
Polyphosphate (polyP) is a conserved inorganic polymer traditionally viewed as a stress-induced phosphate and energy reserve. In cyanobacteria, however, polyP granules are constitutively present and are frequently observed in close proximity to carboxysomes, the bacterial microcompartments that mediate CO2 fixation. Here, we show that polyP functions as a spatially organized regulator of the photosynthetic cytoplasm in Synechococcus elongatus. PolyP granules localize to the nucleoid and are periodically arranged along the cell axis, independent of the McdAB carboxysome positioning system. Despite this independence, polyP and carboxysomes associate non-randomly, and this association is enhanced when active carboxysome positioning by the McdAB system is disrupted. Loss of polyP synthesis leads to nucleoid expansion, an increased number of smaller carboxysomes with high mobility, and severe defects in growth under ambient CO2. Perturbation of polyP turnover further reveals structural connections to both carboxysomes and thylakoid membranes. Together, these findings identify polyP as an architectural integrator that couples chromosome organization, metabolic compartmentalization, and photosynthetic fitness.IMPORTANCEPolyphosphate (polyP) is a ubiquitous storage polymer found across all three domains of life. In bacteria, polyP is involved in virulence, energy metabolism, DNA structure, and stress. Here, we investigate the physical and functional relationships between polyP and the carboxysome-a carbon-fixing organelle that encapsulates the most abundant enzyme on Earth and is responsible for a significant amount of atmospheric CO2 sequestration. We discover that polyP is important for proper carboxysome assembly and organization in the cell and is also required for robust cell growth under ambient CO2 conditions. As carboxysomes are one class of the broader group of bacterial microcompartments, these findings have broader implications for polyP in the function and organization of the bacterial cytoplasm.
Technetium polyphosphate uptake by breast tumours has been investigated in 69 patients. Although 70 per cent (38 out of 54) of malignant tumours took up the isotope in comparison with 45 per cent (5 out of 11) of benign lesions, this technique would be unreliable for diagnostic purposes.
Virtually all of the polyphosphate (PP) present in yeast protoplasts can be recovered in a crude particulate fraction if polybase-induced lysis is used for disrupting the protoplasts. This fraction contains most of the vacuoles, mitochondria and nuclei. Upon the purification of vacuoles the PP is enriched to the same extent as are the vacuolar markers. The amount of PP per vacuole is comparable to the amount of PP per protoplast. The possibility that PP is located in the cell wall is also considered. In the course of the incubation necessary for preparing protoplasts, 20% of the cellular PP is broken down. As this loss of PP occurs to the same extent in the absence of cell wall degrading enzymes, it is inferred that internal PP is metabolically degraded, no PP being located in the cell walls. It is concluded that in Saccharomyces cerevisiae most if not all of the PP is located in the vacuoles, at least under the growth conditions used.
When glycerol was used to induce myxospore formation in Myxococcu xanthus in the presence of 32Pi, the label was incorporated into a variety of acid-soluble compounds. Incorporation into ribonucleotides was approximately fivefold greater than in vegetative cells or noninducible mutants grown in glycerol. The label was also incorporated into some unknown compounds and material tentatively identified as guanosine tetraphosphate. Marked accumulation into polyphosphates, which were present mainly in culture supernatants, occurred relatively late during myxospore formation. The kinetics of accumulation of some of these compounds and their distribution into acid-soluble cell extracts and culture supernatants are described and compared with those in vegetative cells and noninducible mutants.
Stannous salts are used as reducing agents in many radiopharmaceutical kits. Differential pulse polarography, with 1 M sulfuric acid as the supporting electrolyte, is a relatively simple and effective technique for stannous quantitation and can be used in the quality assurance testing of pyrophosphate and polyphosphate radiopharmaceutical kits.
The occurrence of linear condensed polyphosphates and cyclic condensed metaphosphates was studied by means of pulse-labeling with 32P-orthophosphate (3--5h) in a number of Phaeophyceae species: Pylaiella litoralis, Ilea fascia, Ectocarpus siliculosus and also Rhodophyceae species: Ceramiumdeslongchampsii, C. rubrum, Rhodomela confervoides, Porphyridium purpureum and P. aerugineum. Two-dimensional cellulose thin layer chromatography revealed that in all species studied 32P-radioactivity was generally present in all oligopolyphosphates containing 2 to 7 phosphate residues, in cyclic metaphosphates (tri-, tetra-, penta- and hexametaphosphates) and in high-molecular-weight condensed phosphates which remained at the starting point. Among the low-molecular-weight condensed inorganic phosphates the trimetaphosphate had a significantly higher specific activity than the other oligophosphates which were separated on the chromatography plates as measured by the direct scanning with a Geiger-Muller counter. The phosphate uptake strongly depends on the internal pool of reserve phosphates of the algae cells. The 32P-orthophosphate incorporation of the cells is low and sluggish when growning in a synthetic medium or in sea water. Accordingly 32P appeared preferentially in the low-molecular-weight fractions of condensed phosphates since the storage phosphates were not yet used. After previous incubation in a P-free culture medium of the algae the 32P was rather rapidly incorporated and was found mostly in the high-molecular-weight condensed phosphates. During MAK-chromatography the high-molecular-weight fractions were eluted together with the nucleic acids (tRNA and DNA) while most of the low-molecular-weight fractions left the column immediately on elution.
The reactions of glycine with inorganic polyphosphates in the solid state have been studied. The formation of peptides up to the decamer occurs at moderate temperatures(r.t.-100 degrees C) in the presence of imidazole and magnesium chloride. If adenosine 5' -monophosphate is added to the reaction mixture, 2'(3') -o-glycyl adenosine 5'-monophosphate is also obtained. These reactions could have occurred on the primitive earth.
Serum kinetics of Doxycycline polyphosphate (DPP) have been studied in dogs after oral administration of 10 mg.kg-1 by measurement of total serum concentration (Ct) of tetracycline derivatives by a chemical assay and active concentration (Ca) by a microbiological method. Kinetics have been studied using a one compartment open model with absorption by oral route. DPP is rapidly absorbed, the peak serum level is reached three hours after absorption and slowly eliminated (elimination half-life = 12 hours). The main differences observed between Ct and Ca kinetics are in the values of the areas under the curves (AUC) and the peak serum level. The values obtained for these parameters for Ca kinetics were found to be 50% of those obtained for Ct, the volumes of distribution being in inverse proportion. These results are in a good agreement with the correlation and linear regression observed between Ca and Ct showing that 55% of total serum Doxycycline possesses immediate antibacterial activity. It is postulated that this difference between Ct and Ca kinetics is essentially a reflection of the ratios of bound and free drug. Similar results were obtained with the finished pharmaceutical form except for a 15% increase of AUC indicating improvement of the bioavailability of the drug.
A single-column high-performance liquid chromatographic system for the simultaneous separation of bases, nucleosides and nucleoside mono- and polyphosphates has been developed, in which a strong porous anion-exchange resin (Aminex A-14) is used. The chromatographic run, carried out at 55 degrees and at alkaline pH by using a linear gradient both of ionic strength and pH, takes less than 225 min. The quantitative application of the described procedure to the analysis of cell nucleotide pools is reported.
Myocardial imaging with technetium-99m stannous polyphosphate was performed on 46 patients. Eleven patients had no cardiac disease, 22 had acute myocardial infarction, and 13 had stable arteriosclerotic heart disease. Distinct patterns of myocardial activity were noted: (1) the patients with no obvious cardiac disease showed no cardiac activity; (2) stable arteriosclerotic heart disease showed faint, ill-defined cardiac activity, primarily in the anterior or inferior aspect of the left ventricle; (3) acute myocardial infarction showed intense, focal, well-defined activity, with a shape that characterized the location of the infarct.