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PubMed1991

Synthesis of dinucleoside polyphosphates catalyzed by firefly luciferase.

In the presence of ATP, luciferin (LH2), Mg2+ and pyrophosphatase, the firefly (Photinus pyralis) luciferase synthesizes diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A) through formation of the E-LH2-AMP complex and transfer of AMP to ATP. The maximum rate of the synthesis is observed at pH 5.7. The Km values for luciferin and ATP are 2-3 microM and 4 mM, respectively. The synthesis is strictly dependent upon luciferin and a divalent metal cation. Mg2+ can be substituted with Zn2+, Co2+ or Mn2+, which are about half as active as Mg2+, as well as with Ni2+, Cd2+ or Ca2+, which, at 5 mM concentration, are 12-20-fold less effective than Mg2+. ATP is the best substrate of the above reaction, but it can be substituted with adenosine 5'-tetraphosphate (p4A), dATP, and GTP, and thus the luciferase synthesizes the corresponding homo-dinucleoside polyphosphates:diadenosine 5',5"'-P1,P5-pentaphosphate (Ap5A), dideoxyadenosine 5',5"'-P1,P4-tetraphosphate (dAp4dA) and diguanosine 5',5"'-P1,P4-tetraphosphate (Gp4G). In standard reaction mixtures containing ATP and a different nucleotide (p4A, dATP, adenosine 5'-[alpha,beta-methylene]-triphosphate, (Ap[CH2]pp), (S')-adenosine-5'-[alpha-thio]triphosphate [Sp)ATP[alpha S]) and GTP], luciferase synthesizes, in addition to Ap4A, the corresponding hetero-dinucleoside polyphosphates, Ap5A, adenosine 5',5"'-P1,P4-tetraphosphodeoxyadenosine (Ap4dA), diadenosine 5',5"'-P1,P4-[alpha,beta-methylene] tetraphosphate (Ap[CH2]pppA), (Sp-diadenosine 5',5"'-P1,P4-[alpha-thio]tetraphosphate [Sp)Ap4A[alpha S]) and adenosine-5',5"'-P1,P4-tetraphosphoguanosine (Ap4G), respectively. Adenine nucleotides, with at least a 3-phosphate chain and with an intact alpha-phosphate, are the preferred substrates for the formation of the enzyme-nucleotidyl complex. Nucleotides best accepting AMP from the E-LH2-AMP complex are those which contain at least a 3-phosphate chain and an intact terminal pyrophosphate moiety. ADP or other NDP are poor adenylate acceptors as very little diadenosine 5',5"'-P1,P3-triphosphate (Ap3A) or adenosine-5',5"'-P1,P3-triphosphonucleosides (Ap3N) are formed. In the presence of NTP (excepting ATP), luciferase is able to split Ap4A, transferring the resulting adenylate to NTP, to form hetero-dinucleoside polyphosphates. In the presence of PPi, luciferase is also able to split Ap4A, yielding ATP. The cleavage of Ap4A in the presence of Pi or ADP takes place at a very low rate. The synthesis of dinucleoside polyphosphates, catalyzed by firefly luciferase, is compared with that catalyzed by aminoacyl-tRNA synthetases and Ap4A phosphorylase.

Animals↗
PubMed1991

Stimulatory and inhibitory effects of N-methyl-D-aspartate on 3H-inositol polyphosphate accumulation in rat cortical slices.

The actions of the excitatory amino acid N-methyl-D-aspartate (NMDA) on the accumulation of 3H-inositol polyphosphate isomers in rat cerebral cortex slices have been examined over short (less than 5 min) incubation periods. NMDA caused the dose-dependent accumulation of only [3H]inositol monophosphate and [3H]inositol bisphosphate (maximal effect between 0.3 and 1 mM), with no increase in [3H]inositol trisphosphate ([3H]InsP3) and [3H]inositol tetrakisphosphate ([3H]InsP4). HPLC analysis confirmed this, showing no increases in the breakdown products of [3H]Ins(1,3,4,5)P4. When present with the muscarinic agonist carbachol (1 mM), high concentrations of NMDA (1 mM) could almost totally inhibit carbachol-induced accumulation of 3H-inositol polyphosphates. In contrast, at lower concentrations of NMDA (10 microM), the inhibitory effect was replaced with a synergistic accumulation of inositol polyphosphates, especially [3H]InsP4 and [3H]InsP3. The inhibitory effects of NMDA were only apparent when extracellular Ca2+ was present, although incubation in media with no added Ca2+ resulted in somewhat reduced stimulatory responses to NMDA alone, but suppressed totally the inhibitory effects of 1 mM NMDA and reduced the synergistic effects of 10 microM NMDA on carbachol responses. These studies, therefore, reveal Ca(2+)-dependent effects of NMDA indicative of indirect mechanisms of action and show that care must be made in interpreting the effects of NMDA on phosphoinositide metabolism unless the inositol polyphosphate composition has been fully characterised.

Animals↗
PubMed2002

The g5R (D250) gene of African swine fever virus encodes a Nudix hydrolase that preferentially degrades diphosphoinositol polyphosphates.

The African swine fever virus (ASFV) g5R gene encodes a protein containing a Nudix hydrolase motif which in terms of sequence appears most closely related to the mammalian diadenosine tetraphosphate (Ap4A) hydrolases. However, purified recombinant g5R protein (g5Rp) showed a much wider range of nucleotide substrate specificity compared to eukaryotic Ap4A hydrolases, having highest activity with GTP, followed by adenosine 5'-pentaphosphate (p5A) and dGTP. Diadenosine and diguanosine nucleotides were substrates, but the enzyme showed no activity with cap analogues such as 7mGp3A. In common with eukaryotic diadenosine hexaphosphate (Ap6A) hydrolases, which prefer higher-order polyphosphates as substrates, g5Rp also hydrolyzes the diphosphoinositol polyphosphates PP-InsP5 and [PP]2-InsP4. A comparison of the kinetics of substrate utilization showed that the k(cat)/K(m) ratio for PP-InsP5 is 60-fold higher than that for GTP, which allows classification of g5R as a novel diphosphoinositol polyphosphate phosphohydrolase (DIPP). Unlike mammalian DIPP, g5Rp appeared to preferentially remove the 5-beta-phosphate from both PP-InsP5 and [PP]2-InsP4. ASFV infection led to a reduction in the levels of PP-InsP5, ATP and GTP by ca. 50% at late times postinfection. The measured intracellular concentrations of these compounds were comparable to the respective K(m) values of g5Rp, suggesting that one or all of these may be substrates for g5Rp during ASFV infection. Transfection of ASFV-infected Vero cells with a plasmid encoding epitope-tagged g5Rp suggested localization of this protein in the rough endoplasmic reticulum. These results suggest a possible role for g5Rp in regulating a stage of viral morphogenesis involving diphosphoinositol polyphosphate-mediated membrane trafficking.

Acid Anhydride Hydrolases↗
PubMed2000

Diadenosine polyphosphates activate a Ca(2+)-dependent K(+)-conductance in porcine aortic smooth muscle cells via P2-purinoceptors.

Effects of the diadenosine polyphosphates P(1),P(3)-diadenosine triphosphate (Ap3A), P(1),P(4)-diadenosine tetraphosphate (Ap4A), P(1),P(5)-diadenosine pentaphosphate (Ap5A) and P(1), P(6)-diadenosine hexaphosphate (Ap6A) and of adenosine, ATP, ADP, AMP, UTP on smooth muscle cells from porcine aorta were examined. Membrane voltages and cellular conductances were measured in the slow whole cell configuration of the patch clamp technique. All four diadenosine polyphosphates, adenosine, AMP and ADP predominantly hyperpolarized membrane voltages with only occasional transient initial depolarizations whereas ATP and UTP led to sustained depolarizations. All four diadenosine polyphosphates increased cellular conductances. The effects of Ap5A on membrane voltages were almost completely inhibited by the putative P2-purinoceptor antagonist pyridoxal-phosphate-6-azophenyl-2',4'-disulphonic acid (PPADS, 10 micromol/l) and only partially reduced by the putative A(2)-purinoceptor antagonist 3,7-dimethyl-1-propragyl-xanthine (DMPX, 10 micromol/l) or the Ap4A-receptor antagonist diinosine pentaphosphate (Ip5I, 10 micromol/l). The adenosine-induced hyperpolarization was partially reduced by the putative A(1)-purinoceptor antagonist 8-cyclopentyl-1,3-dipropargylxanthine (DPCPX, 0.1 micromol/l) or by DMPX while PPADS or Ip5I were without effects. Ap5A-induced hyperpolarizations were inhibited by Ba(2+) and clotrimazole but not by glibenclamide. We conclude that diadenosine polyphosphates activate predominantly a Ca(2+)-dependent K(+)-conductance in smooth muscle cells obtained from porcine aorta most likely mediated via P2Y-purinoceptors and possibly partially also by Ap4A receptors.

Animals↗
PubMed2002

Control of dinucleoside polyphosphates by the FHIT-homologous HNT2 gene, adenine biosynthesis and heat shock in Saccharomyces cerevisiae.

BACKGROUND: The FHIT gene is lost early in the development of many tumors. Fhit possesses intrinsic ApppA hydrolase activity though ApppA cleavage is not required for tumor suppression. Because a mutant form of Fhit that is functional in tumor suppression and defective in catalysis binds ApppA well, it was hypothesized that Fhit-substrate complexes are the active, signaling form of Fhit. Which substrates are most important for Fhit signaling remain unknown. RESULTS: Here we demonstrate that dinucleoside polyphosphate levels increase 500-fold to hundreds of micromolar in strains devoid of the Saccharomyces cerevisiae homolog of Fhit, Hnt2. Accumulation of dinucleoside polyphosphates is reversed by re-expression of Hnt2 and is active site-dependent. Dinucleoside polyphosphate levels depend on an intact adenine biosynthetic pathway and time in liquid culture, and are induced by heat shock to greater than 0.1 millimolar even in Hnt2+ cells. CONCLUSIONS: The data indicate that Hnt2 hydrolyzes both ApppN and AppppN in vivo and that, in heat-shocked, adenine prototrophic yeast strains, dinucleoside polyphosphates accumulate to levels in which they may saturate Hnt2.

Journal Article↗
PubMed1975

Technetium-99m polyphosphate bone image for early detection of skeletal metastasis. Correlation with other diagnostic parameters.

Technetium 99m-polyphosphate bone images are correlated with bone roentgenography, and serum calcium, phosphorus and alkaline phosphatase in 91 patients with suspected bone metastasis. Technetium polyphosphate bone images are the most sensitive and serum level of calcium and phosphorus are the least sensitive indicator of bone lesions. Bone roentgenography is not as sensitive as technetium polyphosphate images. Abnormal bone images with normal or abnormal bone roentenography associated with increased alkaline phosphatase in the absence of liver metastasis are highly suggestive of metastatic bone disease. Abnormal bone images adjoining the joints, associated with normal serum alkaline phosphatase and abnormal joint roentgenography suggest arthritis. It is recommended that technetium 99m-labelled phosphate bone images are considered to be the diagnostic procedure of choice to detect skeletal lesions. Polyphosphate bone images are highly sensitive, with the combination of elevated alkaline phosphatase they become relatively more specific for a metastatic bone disease.

Alkaline Phosphatase↗
PubMed2002

Polyphosphate kinase genes from activated sludge carrying out enhanced biological phosphorus removal.

The community structure and metabolic function of activated sludge carrying out enhanced biological phosphorus removal have been investigated. Laboratory-scale sequencing batch reactors were operated at several influent COD/P ratios to obtain sludges with a range of phosphorus contents. Molecular microbiological techniques based on small subunit ribosomal RNA were used to characterize the structure of these sludges. The dominant polyphosphate accumulating organism was a close relative of Rhodocyclus tenuis, a member of the beta subclass of the Proteobacteria. Fragments of genes coding for polyphosphate kinase (PPK), thought to be responsible for polyphosphate accumulation, were retrieved from one of the sludges. The relative abundance of PPK gene copies in genomic DNA extracted from sludges was determined to confirm that at least one of the PPK gene sequences was derived from the dominant polyphosphate accumulating organism.

DNA Primers↗
PubMed1975

Kinetics of 99mTc-labeled pyrophosphate and polyphosphate in man.

Thekinetic of 99mTc-labeled pyrophosphate were compared with those of polyphosphate in ten patients in a combined study. Both agents cleared from the blood in a biexpoential fashion. The clearance half-time of Exponent I was the same for both and was shorter than the clearance half-time of Exponent ii. Urinary excretion of both agents was the same during the first hour but during the next 3 hr Tc-pyrophosphate cleared at a slightly more rapid rate, resulting in lower blood background radioactivity. Both agents were bound loosely to plasma proteins, mainly to globulin fractions. The sensitivity of lesion detection was similar for both. Excellent bone images were obtained with both agents. The images with Tc-pyrophosphatewere consistently superior owing to the low blood background and they took less time to accumulate an identical number of counts from identical regions. With the amount of 99mTc-complex used, no hyocalcemia or tetany was noted, nor was there any significant effect on 1-hr serum levels of inorganic phosphours and alkaline phosphatase. Four hours after injection, 9.5% of the dose of Tc-pyrophosphate was circulating in blood, 31.7% was excreted in urine, and the remaining 58.8% was taken up by bone and other tissues. The corresponding values with Tc-polyphosphate were 12.5% in blood, 29.0% in urine, and 58.5% in bone and other tissues. Among the soft tissues, the genitourinary system is most consistently visualized. It is concluded that both Tc-pyroposphate and Tc-polyphosphate are excellent skeletal-imaging agents and that Tc-pyrophosphate appears slightly superior to Tc-polyphosphate.

Blood Proteins↗
PubMed1976

Comparison of 18F and 99mTc-polyphosphate in orthopedic bone scintigraphy.

To compare 99mTc-polyphosphate and 18F for use in orthopedics, 79 patients were examined with both. Fifty cases were suitable for analysis. While the extraskeletal uptake of 18F was found to be negligible, 99mTc-polyphosphate may accumulate considerably in pathologic soft tissue, e.g., in soft-tissue tumors and in inflamed synovial tissue. This soft-tissue Tc accumulation may obscure the osseus uptake, notably in the examination of joint regions, commonly the regions of interest in orthopedics. After simultaneous administration of both agents, quantitative measurements were performed on specimens of bone and synovial tissue from diseased joints in human patients and in rabbits. The uptake of 99mTc-polyphosphate in synovial tissue was shown to be about seven times that of 18F, while their uptakes in bone were equal. In short, 99mTc-polyphosphate, a valuable tracer in general, is hardly the agent of choice in orthopedics.

Adult↗
PubMed1977

[Some pathways of biosynthesis and degradation of polyphosphates from green algae Acetabularia mediterranea].

The activity of ATP: polyphosphate phosphotransferase was detected in free-cellular extracts of Acetabularia mediterranea. The enzyme activity in cells originally deficient in phosphorus and subsequently transferred into the phosphate-containing medium increases 5-10-fold as compared to normal. Polyphosphate degradation in A. mediterranea is probably produced by polyphosphatase, which was also detected in the free-cellular extract. It was shown that the polyphosphatase activity has two pH optima, i.e. 4.5 and 7.5, and is considerably increased when the cells are transferred into the phosphate-free medium. It is assumed that high-molecular polyphosphates involved in A. Mediterranea metabolism are responsible for regulation of orthophosphate and ATP level in the cells by ATP: polyphosphate phosphotransferase and polyphosphatase.

Acetabularia↗
PubMed1981

Guanosine polyphosphate production of Escherichia coli stringent and relaxed strains in the stationary phase of growth.

Stringent and relaxed Escherichia coli strains grown on minimal and on differently enriched media produced guanosine polyphosphates in the stationary phase of growth. On transition from the logarithmic to the stationary phase, stringent strains started to produce guanosine 5' triphosphate 3' diphosphate (pppGpp). and guanosine 5' diphosphate 3' diphosphate (ppGpp), while relaxes strains accumulated only ppGpp. When the stringent strain was cultivated on media enriched with Casamino Acids the leve of pppGpp decreased, while with yeast extract an almost twofold increase could be observed. The concentration of ppGpp increased with both nutrients as compared to that measured in minimal medium. Readdition of glucose to the stationary phase culture did not result in the slightest decrease of the nucleoside polyphosphate levels. In contrast, addition of a mixture of 20 L-amino acids or Casamino Acids or yeast extract to the medium caused an abrupt decrease in the guanosine polyphosphate levels. Qualitatively similar results were obtained with the relaxed strains except that the amounts of ppGpp were smaller than in the case of the stringent counterpart and the responses to the resupplementation were slower. Some possible mechanisms regarding the occurrence of guanosine polyphosphates in the stationary phase are discussed.

Culture Media↗
PubMed1994

Generation of a proton motive force by the excretion of metal-phosphate in the polyphosphate-accumulating Acinetobacter johnsonii strain 210A.

The strictly aerobic, polyphosphate-accumulating Acinetobacter johnsonii strain 210A degrades its polyphosphate when oxidative phosphorylation is impaired. The endproducts of this degradation, divalent metal ions and inorganic phosphate, are excreted as a neutral metal-phosphate (MeHPO4) chelate via the electrogenic MeHPO4/H+ symport system of the organism. The coupled excretion of MeHPO4 and H+ in A. johnsonii 210A can generate a proton motive force. In membrane vesicles and deenergized cells, a membrane potential of about -70 mV and transmembrane pH gradient of about -8 mV were formed in response to an imposed outwardly directed MeHPO4 concentration gradient of 120 mV (initial value). The MeHPO4 efflux-induced proton motive force could drive energy-requiring processes, such as the accumulation of L-proline and L-lysine and the synthesis of ATP via the membrane-bound F0F1 H(+)-ATPase. In vivo 31P NMR studies of polyphosphate degradation in anaerobic cell suspensions revealed the presence of a considerable outwardly directed phosphate gradient across the cytoplasmic membrane corresponding to a MgHPO4 concentration gradient of at least 100 mV. This MgHPO4 concentration gradient was maintained for several hours. Thus, energy recycling by MeHPO4/H+ efflux will contribute significantly to the overall production of metabolic energy from the degradation of polyphosphate in A. johnsonii 210A.

Acinetobacter↗
PubMed1994

Inositol polyphosphate 1-phosphatase is present in the nucleus and inhibits DNA synthesis.

Inositol polyphosphate 1-phosphatase, an enzyme of the phosphatidylinositol signaling pathway, hydrolyzes the 1-phosphate from inositol 1,4-bisphosphate and inositol 1,3,4-trisphosphate. We have used indirect immunofluorescence microscopy, Western blot analysis, and enzyme assays to determine the cellular localization of the enzyme. We find that the enzyme is present, but not exclusively, in the nucleus of Madin-Darby bovine kidney cells, and also in COS-7 and HeLa cells that were transiently transfected with a cDNA encoding bovine inositol polyphosphate 1-phosphatase. DNA synthesis, as measured in COS-7 and HeLa cells transiently over-expressing enzyme, was reduced 50% in cells transfected with wild-type enzyme compared with nontransfected cells or cells transfected with an inactive mutant form of the enzyme. These data demonstrate that this response is mediated by one of the substrates or products of inositol polyphosphate 1-phosphatase. We propose that overexpressed inositol polyphosphate 1-phosphatase degrades a stimulatory inositol phosphate(s) and thereby inhibits DNA synthesis.

Amino Acid Sequence↗
PubMed1996

Expression of polyphosphate kinase inhibits the glucose uptake in Escherichia coli.

This paper examines the effects of phosphate pool and expression of polyphosphate kinase on glucose uptake by expressing the polyphosphate kinase under the control of lac promoter. The E. coli transformant of pL1, containing an IPTG controllable element for polyphosphate kinase expression, showed that the total intracellular phosphate significantly increased. However, the rate of glucose uptake by the resting plasmid-bearing cells with IPTG induction significantly decreased. These findings suggest that the polyphosphate can not directly function as an energy source in E. coli or at least not as a good energy supplier.

Biological Transport↗
PubMed1993

The polyphosphate- and ATP-dependent glucokinase from Propionibacterium shermanii: both activities are catalyzed by the same protein.

The glucokinase (EC 2.7.1.63) from Propionibacterium shermanii phosphorylates glucose using inorganic polyphosphate (poly(P)) or ATP as the phosphate donor. In this investigation, we have purified the glucokinase to homogeneity, using two methods and show that the polyphosphate and ATP-dependent glucokinase activities eluted as a single protein. The protein peak is shown to be homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, reverse phase HPLC, and N-terminal sequence analysis. The purified protein eluted as a single peak from gel filtration and hydrophobic interaction HPLC columns and was found to display both the poly(P) and ATP glucokinase activities. Likewise, the two activities comigrated on a native isoelectric focusing gel. In addition, two analogues of ATP with different reactive groups displayed different inhibition patterns with respect to ATP and poly(P). The 2',3'-dialdehyde of ATP, whose reactive group is the dialdehyde of the ribose ring, showed competitive and noncompetitive patterns with respect to ATP and poly(P), respectively. While, 5'-p-fluorosulfonylbenzoyl adenosine, whose reactive sulfonyl fluoride group is related to the gamma-phosphoryl group of ATP, displayed competitive inhibition patterns with both ATP and poly(P). These observations provide evidence that the polyphosphate and ATP-dependent glucokinase activities of P. shermanii are the catalytic properties of a single enzyme and that the two substrates may have different binding sites on the enzyme with a common phosphorylating center.

Adenosine Triphosphate↗
PubMed1994

Preparation and use of polyphosphate-modified zirconia for purification of nucleic acids and proteins.

Polyphosphates of chain lengths between 3 and 100 were coupled to porous zirconia particles and used for affinity chromatography of nucleic acids and proteins. It is demonstrated that single-stranded RNA and DNA are strongly retained on the polyphosphate-modified zirconia support, while double-stranded DNA is only weakly bound if at all. Protein separation on this packing can be performed by applying both high-performance liquid chromatography and batch procedures. The results show that polyphosphate-modified zirconia is a useful affinity packing for immobilization and purification of biomacromolecules.

Alkaline Phosphatase↗
PubMed1988

Effect of cadmium ions on dioxygen affinity and polyphosphate activity of human red blood cells.

The effect of cadmium ions on the dioxygen affinity, the time-dependent depletion of intracellular polyphosphates, and the elongation of human red blood cells (RBC's) was examined. The incubation of RBC's in the presence of 1 mM Cd2+ at 37 degrees C for more than one hour results in a decrease of the p50 value by 2.5-3.0 mmHg in comparison to controls. The p50 of stripped (phosphate-free) hemoglobin is not affected by the presence of 1 mM Cd2+ (p50 = 4.8 mmHg at pH 7.2 and 37 degrees C). Experiments with RBC cryolysates demonstrate an apparently competitive effect of 2.3-bisphosphoglycerate (DPG) with cadmium ions on the dioxygen affinity. From 31P NMR spectra, 31P T1 relaxation, and 31P T2 relaxation behavior a more direct evidence for DPG-Cd2+ complexation is obtained. 31P NMR spectra of RBC cryolysates also indicate DPG-Cd2+ complexation. The hydrolysis of free polyphosphates in RBC's incubated at 37 degrees C as monitored by 31P NMR spectra can be noticed after a three-hour lag phase (constant polyphosphate level). This lag phase is lengthened from three hours to four hours in the presence of Cd2+ ions. RBC elongation, as a measure of deformability, decreases slightly upon incubation with 1 mM Cd2+.

Cadmium↗
PubMed1985

Control of yeast neutral trehalase by distinct polyphosphates and ribonucleic acid.

The activity of yeast trehalase when assayed at pH 7 in a crude extract was found to increase 2- to 3-fold upon incubation with 0.1% (v/v) polyethyleneimine or other polycations such as polylysine (0.075-mMol) and calf thymus histones (0.08 mMol). Incubation with 3 mM-Mn2+ and 5 mM-Ca2+ also led to 3- and 1.6-fold increases in trehalase activity, respectively. The activities of 11 other enzymes assayed in the crude yeast extract did not increase after addition of polyethylene imine. At concentrations of polyethyleneimine that maximally stimulated trehalase activity, 97% of the total RNA present in the crude extract, 40% of total protein, and 60% of the polyphosphate (assayed as inorganic phosphate liberated during 7 min incubation at 95 degrees C and pH O) were found to be precipitated. A similar finding was made with trehalase-stimulating concentrations of Mn2+. Activation of trehalase by polyethylene imine rendered this enzyme susceptible to inhibition by a preparation of total yeast RNA, inorganic polyphosphates, and related polyanions. We present further evidence that the removal of a distinct RNA and/or polyphosphate is the basic principle of polyethyleneimine-induced activation of trehalase. A more pronounced stimulation of trehalase activity (4-fold) could be obtained by enzymatic phosphorylation with ATP in the presence of cyclic AMP and Mg2+ as described by van Solingen and van der Plaat (1975) [9].(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗