Polyphosphate acid-insoluble

The earlier work on the isolation of PolyPs from the cells of living organisms usually employed the same methods as those used for the extraction of nucleic acids. It was not until 1936 that MacFarlane (MacFarlane, 1936) proposed a specific method for the extraction and fractionation of condensed phosphates present in cells. It was found that these phosphates could be divided into two main fractions, i.e. one soluble in 5 % trichloroacetic acid (TCA) and the other insoluble, and ever since then cellular condensed polyphosphates have been divided into acid-soluble and acid-insoluble fractions. 

Figure 7.5 Changes in (a) PolyP content, (b and c) PolyP-metabolizing enzymes activities, and (c) biomass and production of chlortetracycline during growth of the low-producing strain of Strepto-myces aureofaciens 2209 (Kulaev et al., 1976). (a) (1) total acid-insoluble PolyP (2) PolyP extracted with hot perchloric acid (3) salt-soluble PolyP (b) (1) polyphosphate kinase (centre scale) (2) 1,3-diphosphoglycerate-polyphosphate phosphotransferase (right-hand scale) (3) PolyP glucokinase (left-hand scale) (c) (1) biomass (2) chlortetracycline (3) exopolyphosphatase with PolyP29o (4) pyrophosphatase (5) tripolyphosphatase.

K. K. Tewari and M. Singh (1964). Acid-soluble and acid-insoluble inorganic polyphosphates in... 

If ferrous ions are present during assays of DNA and RNA polymerases in which radioactive newly synthesized polynucleotides are precipitated on to filter paper discs in trichloroacetic acid, spuriously high results are obtained, apparently due to acid-insoluble complexes of Fe with substrate nucleotides precipitating on the paper. Clearly ferrous ions should be avoided in assays of this type. The complex Al. ATP is a potent inhibitor of hexokinase, and neutron activation analysis of many commercial samples of ATP has shown that Al is ubiquitous, and the most common metal contaminant It is best removed by passing the ATP preparation over a cellulose polyphosphate column at pH 5. Chelates of ATP with divalent metal ions have been separated from non-chelated ATP using reverse-phase h.p.l.c. ... 

Magnesium oxide forms precipitates with fluorine in the reactor, which may blind the filter cloth therefore, high MgO content is considered undesirable. When phosphoric acid is used to produce ammonium phosphates or polyphosphates, water-insoluble (but citrate-soluble) magnesium ammonium phosphate compounds may be formed, These compounds form troublesome impurities in liquid fertilizers. 

Propionibacteria contain large amounts of polyphosphates. High-molecular-weight (acid-insoluble) compounds containing from 70 to 500 residues of... 

Table 4.12. Acid-insoluble polyphosphates in P. shermanii under different conditions of cultivation...

The first two components are the active surfactants, whereas the other components are added for a variety of reasons. The polyphosphate chelate Ca ions which are present (with Mg ions also) in so-called hard waters and prevents them from coagulating the anionic surfactants. Zeolite powders are often used to replace phosphate because of their nutrient properties in river systems. Sodium silicate is added as a corrosion inhibitor for washing machines and also increases the pH. The pH is maintained at about 10 by the sodium carbonate. At lower pH values the acid form of the surfactants are produced and in most cases these are either insoluble or much less soluble than the sodium salt. Sodium sulphate is added to prevent caking and ensures free-flowing powder. The cellulose acts as a protective hydrophilic sheath around dispersed dirt particles and prevents re-deposition on the fabric. Foam stabilizers (non-ionic surfactants) are sometimes added to give a... 

Casein may be coagulated and recovered as rennet casein by treatment of milk with selected proteinases (rennets). However, one of the caseins, K-casein, is hydrolysed during renneting and therefore the properties of rennet casein differ fundamentally from those of acid casein. Rennet casein, which contains the colloidal calcium phosphate of milk, is insoluble in water at pH 7 but can be dissolved by adding calcium sequestering agents, usually citrates or polyphosphates. It has desirable functional properties for certain food applications, e.g. in the production of cheese analogues. 

Many thousands of phosphorus compounds have been described as having flame-retardant utility. The compounds demonstrating commercial utility arc much more limited in number. They include inorganic phosphorus compounds [red phosphorus, ammonium phosphates. insoluble ammonium polyphosphate, phosphoric acid-bascd systems for cellulosics). additive organic phosphorus flstme retardants... 

Ammonium polyphosphates, on the other hand, are relatively water insoluble, nonmelting solids with very high phosphorus contents (up to about 30%). There are several crystalline forms and the commercial products differ in molecular weights, particle sizes, solubilities, and so on. They are also widely used as components of intumescent paints and mastics where they function as the acid catalyst (i.e., by producing phosphoric acid upon decomposition). They are used in paints with pentaerythritol (or with a derivative of pentaerythritol) as the carbonific component and melamine as the spumific compound.22 In addition, the intumescent formulations typically contain resinous binders, pigments, and other fillers. These systems are highly efficient in flame-retarding hydroxy-lated polymers. 

If a water sample contains both soluble and insoluble manganese (Mn) compounds and ions, and it is filtered to separate the dissolved and insoluble fractions, and the filtrate and insoluble residue are analyzed separately, the results can be expressed as total dissolved Mn and total suspended or insoluble Mn. Phosphorus (P) can be determined colorimet-rically as the ortho-phosphate ion, P043, in aqueous samples after a reaction that forms an intensely blue-colored derivative. However polyphosphate ions and other ions and compounds containing P do not form this derivative. Total P in a sample can be determined with the same colorimetric procedure after acid hydrolysis and oxidation of all ions and compounds containing P to P04 3. In some elemental analyses the sample is treated with reagents designed to make available for measurement some fraction of an element or elements but not the total amount. For example, a soil sample may be treated with water at pH 3 to simulate the leaching process of acid rain. A total elemental analysis of the filtrate provides information about just those elements solubilized by the mild acid treatment. This can be called the determination of total mild acid leachable elements. 

Sodium Metaphosphate, Insoluble, occurs as a white, crystalline powder. It is a high-molecular-weight sodium polyphosphate composed of two long metaphosphate chains (NaP03) that spiral in opposite directions about a common axis. The Na20/P205 ratio is about 1.0. It is practically insoluble in water but dissolves in mineral acids and in solutions of potassium and ammonium (but not sodium) chlorides. The pH of a 1 3 slurry in water is about 6.5. 

Sequestrants can bind Ca or Mg ions present in hard water, thus blocking the formation of insoluble soaps or other salts during washing and rising. They can also improve, to a lesser extent, product stability by preventing catalytic decomposition of coloring agents and perfumes in the presence of trace metal ions [97], Citric acid, EDTAand its salts, and polyphosphates are commonly used sequestrants [63]. 

EINECS 256-779-4 Grahamsches sdz Metaphosphoric acid, sodium salt Natrium polymetaphosphat Sodium metaphosphate Sodium metapolyphosphate Sodium polymetaphosphate Sodium polyphosphate. Water softener and detergent. Solid mp = 628° d n 2.181 soluble in H2O. insoluble in organic solvents LD50 (rat ori) = 6200 mgikg. PMC. 

Film-forming anions (phosphates, polyphosphates, and carbonates) can also form sparingly soluble salts on the metal surface that hamper corrosion propagation. These anions can become an active part of rust converters that transform corrosion products into insoluble compounds. For instance, orthophosphoric acid transforms rust into insoluble iron phosphates. 

Sodium metaphosphate CAS 10361-03-2 EINECS/ELINCS 233-782-9 Synonyms Graham s salt IMP Insoluble metaphosphate Insoluble sodium metaphosphate Kurrol s salt Maddrell s salt Metaphos Metaphosphoric acid, sodium salt Polymeric sodium metaphosphate Poly (sodium metaphosphate) Sodium metaphosphate, insoluble Sodium polyphosphates, glassy Sodium tetrapolyphosphate Empirical O3P Na... 

Phosphoramidic acid is somewhat stronger than phosphorodiamidic acid (Table 5.24). If phosphoramidic acid is heated for several hours at 100°C, it isomerises to a very soluble ammonium polyphosphate, by a process which is probably connected with zwitterion formation (7.59). If carbon dioxide is passed into a solution of Na2P03NH2, the relatively insoluble monosodium salt is obtained, which contains the zwitterion (7.60a). Isoelectronic sulphamic acid (7.60b) also exists as a zwitterion [9]. 

The absorption of polyphosphate anions is believed to take place primarily on the positively charged edges of the plate-like clay particles, although there is evidence that some absorption on the plate faces may also occur (Figure 12.13b). At the edges of the clay particles, the polyphosphate anions have easier access to the AF+ cations in the clay (Figure 5.55), which are then believed to be complexed. Under acid conditions this AP may be extracted and insoluble aluminium phosphates formed. This happens with phosphoric acid soil stabilisation (Chapter 5.1) and in the setting of some refractory cements (Section 12.10). 

An early fire-retardant treatment for paper and cotton was to heat them with phosphoric acid and urea at 145-180°C to form insoluble ammonium polyphosphate, (NH4P03) . Ammonium polyphosphate is also used in intumescent paint formulations, where, like the orthophosphate, it releases ammonia and phosphoric acid on heating. The latter facilitates charring which, together with the release of ammonia, retards local combustion. A similar mechanism is believed to account, at least in part, for the fire-retardant action of many other phosphorus compounds. There is now evidence that impregnation of wood with phosphoric acid suppresses the formation of carcinogenic materials during pyrolysis [39]. 

Heating of ammonium phosphates imder an atmosphere of ammonia or in the presence of urea produces ammonium polyphosphate (21,22). At a high degree of polymerization, the product is a water-insoluble solid. This form of ammonium polyphosphate is used commercially as a flame-retardant additive for plastics and as the latent acid component in intnmescent paints, mastics, and caulks (23,24). The water resistance can be fnrther enhanced by encapsulation with a resin. 

The low MW P(3HB) which is also known as complexed-P(3HB) (c-P(3HB)) is an ubiquitous cell constituent that exists in eubacteria, archaebacteria and eukaryotes [22, 23]. Studies have also revealed the presence of c-P(3HB) in hnmans [24]. This c-P(3HB) consists of about 120-200 3-hydroxybutyrate (3HB) units and has a MW of about 12,000 Da [25]. Depending on the strength of their association with macromolecules, chloroform-soluble and chloroform-insoluble c-P(3HB) have been identified [26]. The former forms a weakly bound (noncovalent) complex with polyphosphate salts while the latter nsnally forms a strongly bound (covalent) complex with proteins. These complexes are thought to function as ion (Csd ) transport channels across cell membranes and may also facilitate the uptake of extracellular deoxyribonucleic acid (DNA) material [26, 27]. 

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