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Masayoshi Maeshima - One of the best experts on this subject based on the ideXlab platform.
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vacuolar h Pyrophosphatase and cytosolic soluble Pyrophosphatases cooperatively regulate pyrophosphate levels in arabidopsis thaliana
The Plant Cell, 2018Co-Authors: Shoji Segami, Ali Ferjani, Takaaki Tomoyama, Shingo Sakamoto, Shizuka Gunji, Mayu Fukuda, Satoru Kinoshita, Nobutaka Mitsuda, Masayoshi MaeshimaAbstract:Inorganic pyrophosphate (PPi) is a phosphate donor and energy source. Many metabolic reactions that generate PPi are suppressed by high levels of PPi. Here, we investigated how proper levels of cytosolic PPi are maintained, focusing on soluble Pyrophosphatases (AtPPa1 to AtPPa5; hereafter PPa1 to PPa5) and vacuolar H+-Pyrophosphatase (H+-PPase, AtVHP1/FUGU5) in Arabidopsis thaliana In planta, five PPa isozymes tagged with GFP were detected in the cytosol and nuclei. Immunochemical analyses revealed a high abundance of PPa1 and the absence of PPa3 in vegetative tissue. In addition, the heterologous expression of each PPa restored growth in a soluble PPase-defective yeast strain. Although the quadruple knockout mutant plant ppa1 ppa2 ppa4 ppa5 showed no obvious phenotypes, H+-PPase and PPa1 double mutants (fugu5 ppa1) exhibited significant phenotypes, including dwarfism, high PPi concentrations, ectopic starch accumulation, decreased cellulose and callose levels, and structural cell wall defects. Altered cell arrangements and weakened cell walls in the root tip were particularly evident in fugu5 ppa1 and were more severe than in fugu5 Our results indicate that H+-PPase is essential for maintaining adequate PPi levels and that the cytosolic PPa isozymes, particularly PPa1, prevent increases in PPi concentrations to toxic levels. We discuss fugu5 ppa1 phenotypes in relation to metabolic reactions and PPi homeostasis.
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keep an eye on ppi the vacuolar type h Pyrophosphatase regulates postgerminative development in arabidopsis
The Plant Cell, 2011Co-Authors: Ali Ferjani, Masayoshi Maeshima, Shoji Segami, Gorou Horiguchi, Yukari Muto, Hirokazu TsukayaAbstract:Postgerminative growth of seed plants requires specialized metabolism, such as gluconeogenesis, to support heterotrophic growth of seedlings until the functional photosynthetic apparatus is established. Here, we show that the Arabidopsis thaliana fugu5 mutant, which we show to be defective in AVP1 (vacuolar H+-Pyrophosphatase), failed to support heterotrophic growth after germination. We found that exogenous supplementation of Suc or the specific removal of the cytosolic pyrophosphate (PPi) by the heterologous expression of the cytosolic inorganic Pyrophosphatase1 (IPP1) gene from budding yeast (Saccharomyces cerevisiae) rescued fugu5 phenotypes. Furthermore, compared with the wild-type and AVP1Pro:IPP1 transgenic lines, hypocotyl elongation in the fugu5 mutant was severely compromised in the dark but recovered upon exogenous supply of Suc to the growth media. Measurements revealed that the peroxisomal β-oxidation activity, dry seed contents of storage lipids, and their mobilization were unaffected in fugu5. By contrast, fugu5 mutants contained ~2.5-fold higher PPi and ~50% less Suc than the wild type. Together, these results provide clear evidence that gluconeogenesis is inhibited due to the elevated levels of cytosolic PPi. This study demonstrates that the hydrolysis of cytosolic PPi, rather than vacuolar acidification, is the major function of AVP1/FUGU5 in planta. Plant cells optimize their metabolic function by eliminating PPi in the cytosol for efficient postembryonic heterotrophic growth.
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Molecular Cloning of Vacuolar H+-Pyrophosphatase and Its Developmental Expression in Growing Hypocotyl of Mung Bean
Plant physiology, 1998Co-Authors: Yoichi Nakanishi, Masayoshi MaeshimaAbstract:Vacuolar proton-translocating inorganic Pyrophosphatase and H(+)-ATPase acidify the vacuoles and power the vacuolar secondary active transport systems in plants. Developmental changes in the transcription of the Pyrophosphatase in growing hypocotyls of mung bean (Vigna radiata) were investigated. The cDNA clone for the mung bean enzyme contains an uninterrupted open reading frame of 2298 bp, coding for a polypeptide of 766 amino acids. Hypocotyls were divided into elongating and mature regions. RNA analysis revealed that the transcript level of the Pyrophosphatase was high in the elongating region of the 3-d-old hypocotyl but was extremely low in the mature region of the 5-d-old hypocotyl. The level of transcript of the 68-kD subunit of H(+)-ATPase also decreased after cell maturation. In the elongating region, the proton-pumping activity of Pyrophosphatase on the basis of membrane protein was 3 times higher than that of H(+)-ATPase. After cell maturation, the Pyrophosphatase activity decreased to 30% of that in the elongating region. The decline in the Pyrophosphatase activity was in parallel with a decrease in the enzyme protein content. These findings indicate that the level of the Pyrophosphatase, a main vacuolar proton pump in growing cells, is negatively regulated after cell maturation at the transcriptional level.
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H(+)-translocating inorganic Pyrophosphatase of plant vacuoles. Inhibition by Ca2+, stabilization by Mg2+ and immunological comparison with other inorganic Pyrophosphatases.
European journal of biochemistry, 1991Co-Authors: Masayoshi MaeshimaAbstract:The effects of divalent cations, especially Ca2+ and Mg2+, on the proton-translocating inorganic Pyrophosphatase purified from mung bean vacuoles were investigated to compare the enzyme with other Pyrophosphatases. The Pyrophosphatase was irreversibly inactivated by incubation in the absence of Mg2+. The removal of Mg2+ from the enzyme increased susceptibility to proteolysis by trypsin. Vacuolar Pyrophosphatase required free Mg2+ as an essential cofactor (K0.5 = 42 microM). Binding of Mg2+ stabilizes and activates the enzyme. The formation of MgPPi is also an important role of magnesium ion. Apparent Km of the enzyme for MgPPi was about 130 microM. CaCl2 decreased the enzyme activity to less than 60% at 40 microM, and the inhibition was reversed by EGTA. Pyrophosphatase activity was measured under different conditions of Mg2+ and Ca2+ concentrations at pH 7.2. The rate of inhibition depended on the concentration of CaPPi, and the approximate Ki for CaPPi was 17 microM. A high concentration of free Ca2+ did not inhibit the enzyme at a low concentration of CaPPi. It appears that for Ca2+, at least, the inhibitory form is the Ca2(+)-PPi complex. Cd2+, Co2+ and Cu2+ also inhibited the enzyme. The antibody against the vacuolar Pyrophosphatase did not react with rat liver mitochondrial or yeast cytosolic Pyrophosphatases. Also, the antibody to the yeast enzyme did not react with the vacuolar enzyme. Thus, the catalytic properties of the vacuolar Pyrophosphatase, such as Mg2+ requirement and sensitivity to Ca2+, are common to the other Pyrophosphatases, but the vacuolar enzyme differs from them in subunit mass and immunoreactivity.
Michael E. Salvucci - One of the best experts on this subject based on the ideXlab platform.
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purification and properties of a unique nucleotide Pyrophosphatase phosphodiesterase i that accumulates in soybean leaves in response to fruit removal
Plant Physiology, 1995Co-Authors: Michael E. Salvucci, S J CraftsbrandnerAbstract:Several unique proteins accumulate in soybean (Glycine max) leaves when the developing fruits are removed. In the present study, elevated levels of nucleotide Pyrophosphatase and phosphodiesterase I activities were present in leaves of defruited soybean plants. The soluble enzyme catalyzing these reactions was purified nearly 1000-fold, producing a preparation that contained a single 72-kD polypeptide. The molecular mass of the holoenzyme was approximately 560 kD, indicating that the native enzyme was likely octameric. The purified enzyme hydrolyzed nucleotide-sugars, nucleotide di- and triphosphates, thymidine monophosphate p-nitrophenol, and inorganic pyrophosphate but not nucleotide monophosphates, sugar mono- and bisphosphates, or NADH. The subunit and holoenzyme molecular masses and the preference for substrates distinguish the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I from other plant nucleotide Pyrophosphatase/phosphodiesterase I enzymes. Also, the N-terminal sequence of the soybean leaf enzyme exhibited no similarity to the mammalian nucleotide Pyrophosphatase/phosphodiesterase I, soybean vegetative storage proteins, or other entries in the data bank. Thus, the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I appears to be a heretofore undescribed protein that is physically and enzymatically distinct from nucleotide Pyrophosphatase/phosphodiesterase I from other sources, as well as from other phosphohydrolytic enzymes that accumulate in soybean leaves in response to fruit removal.
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Purification and Properties of a Unique Nucleotide Pyrophosphatase/Phosphodiesterase I That Accumulates in Soybean Leaves in Response to Fruit Removal
Plant Physiology, 1995Co-Authors: Michael E. Salvucci, S. J. Crafts-brandnerAbstract:Several unique proteins accumulate in soybean (Glycine max) leaves when the developing fruits are removed. In the present study, elevated levels of nucleotide Pyrophosphatase and phosphodiesterase I activities were present in leaves of defruited soybean plants. The soluble enzyme catalyzing these reactions was purified nearly 1000-fold, producing a preparation that contained a single 72-kD polypeptide. The molecular mass of the holoenzyme was approximately 560 kD, indicating that the native enzyme was likely octameric. The purified enzyme hydrolyzed nucleotide-sugars, nucleotide di- and triphosphates, thymidine monophosphate p-nitrophenol, and inorganic pyrophosphate but not nucleotide monophosphates, sugar mono- and bisphosphates, or NADH. The subunit and holoenzyme molecular masses and the preference for substrates distinguish the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I from other plant nucleotide Pyrophosphatase/phosphodiesterase I enzymes. Also, the N-terminal sequence of the soybean leaf enzyme exhibited no similarity to the mammalian nucleotide Pyrophosphatase/phosphodiesterase I, soybean vegetative storage proteins, or other entries in the data bank. Thus, the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I appears to be a heretofore undescribed protein that is physically and enzymatically distinct from nucleotide Pyrophosphatase/phosphodiesterase I from other sources, as well as from other phosphohydrolytic enzymes that accumulate in soybean leaves in response to fruit removal.
Jose Carlos Cameselle - One of the best experts on this subject based on the ideXlab platform.
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Mn2+-dependent ADP-ribose/CDP-alcohol Pyrophosphatase: a novel metallophosphoesterase family preferentially expressed in rodent immune cells
Biochemical Journal, 2008Co-Authors: Jose Canales, Ascension Fernandez, Jose Carlos Cameselle, João Meireles Ribeiro, Alicia Cabezas, Joaquim Rui Rodrigues, Maria Jesus CostasAbstract:The Mn2+-dependent ADP-ribose/CDP-alcohol Pyrophosphatase (ADPRibase-Mn) is isolated from rat liver supernatants after separation from Mg2+-activated ADP-ribose Pyrophosphatases devoid of CDP-alcohol Pyrophosphatase activity (ADPRibase-I and ADPRibase-II). The latter are putative Nudix hydrolases, while the molecular identity of ADPRibase-Mn is unknown. MALDI mass spectrometry data from rat ADPRibase-Mn pointed to a hypothetical protein that was cloned and expressed, and showed the expected specificity. It is encoded by the RGD1309906 rat gene, so far annotated just as 'hydrolase'. ADPRibase-Mn is not a Nudix hydrolase, but it shows the sequence and structural features typical of the metallophosphoesterase superfamily. It may constitute a protein family of their own, which appears to be specific to vertebrates, plants and algae. ADP-ribose was successfully docked to a model of rat ADPRibase-Mn revealing its putative active centre. Microarray data from the GEO database indicated the mouse gen 2310004I24Rik, orthologous of RGD1309906, is preferentially expressed in immune cells. This was confirmed by northern and activity assay of ADPRibase-Mn in rat tissues. A possible role of ADPRibase-Mn in immune cell signaling is suggested by the second messenger role of ADP-ribose, that activates TRPM2 ion channels as a mediator of oxidative/nitrosative stress, and by the signaling function assigned to many of the microarray profile neighbours of 2310004I24Rik. Furthermore, an influence of ADPRibase-Mn in the CDP-choline or CDP-ethanolamine pathways of phospholipid biosynthesis cannot be discarded.
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Human placenta hydrolases active on free ADP-ribose: an ADP-sugar Pyrophosphatase and a specific ADP-ribose Pyrophosphatase.
Biochimica et biophysica acta, 2001Co-Authors: João Meireles Ribeiro, Maria Jesus Costas, António Carloto, Jose Carlos CameselleAbstract:Free ADP-ribose has a reducing ribose moiety and it is hazardous due to its nonenzymic reactivity toward protein side chains. ADP-ribose hydrolases are putative protective agents to avoid the intracellular accumulation of ADP-ribose. In mammalian sources, two types of enzymes with ADP-ribose hydrolase activity are known: (i) highly specific ADP-ribose Pyrophosphatases, which in a Mg2+-dependent fashion hydrolyse only ADP-ribose and the nonphysiological analogue IDP-ribose, and (ii) less specific nucleoside diphosphosugar or diphosphoalcohol (NDP-X) Pyrophosphatases, which besides A(I)DP-ribose hydrolyse also some nonreducing NDP-X substrates. So far, of these two enzyme types only the less specific one has been reported in human sources: an ADP-sugar Pyrophosphatase purified from erythrocytes or expressed from cDNA clones. Here we report that human placenta extracts contain two ADP-ribose hydrolases, which were characterised after a near 1000-fold purification. One is an ADP-sugar Pyrophosphatase: it hydrolysed ADP-ribose, ADP-glucose and ADP-mannose, but not e.g. UDP-glucose, at similar rates. It resembles the erythrocyte and recombinant enzyme(s), but showed a 5–20-fold lower Km for ADP-ribose (7 μM). The other enzyme is a highly specific ADP-ribose Pyrophosphatase (the first of this kind to be reported in humans): it hydrolysed only ADP-ribose and IDP-ribose at similar rates, with a very low, 0.4 μM Km for the former. This is a major candidate to control the accumulation of free ADP-ribose in humans. It remains to be seen whether it belongs to the ‘nudix’ protein family, which includes several ADP-ribose hydrolases and other ‘housecleaning’ enzymes (M.J. Bessman, D.N. Frick, S.F. O’Handley, J. Biol. Chem. 271 (1996) 25059-25062).
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rat liver nucleoside diphosphosugar or diphosphoalcohol Pyrophosphatases different from nucleotide Pyrophosphatase or phosphodiesterase i substrate specificities of mg2 and or mn2 dependent hydrolases acting on adp ribose
Biochimica et Biophysica Acta, 1995Co-Authors: Jose Canales, Rosa Maria Pinto, Maria Jesus Costas, Maria Teresa Hernandez, Asuncion Miro, Diego Bernet, Ascension Fernandez, Jose Carlos CameselleAbstract:Abstract Three rat liver nucleoside(5′) diphosphosugar (NDP-sugar) or nucleoside(5′) diphosphoalcohol Pyrophosphatases are described: two were previously identified in experiments measuring Mg 2+ -dependent ADP-ribose Pyrophosphatase activity (Miro et al. (1989) FEBS Lett. 244, 123–126), and the other is a new, Mn 2+ -dependent ADP-ribose Pyrophosphatase. They are resolved by ion-exchange chromatography, and differ by their substrate and cation specificities, K M values for ADP-ribose, pH-activity profiles, molecular weights and isoelectric points. The enzymes were tested for activity towards: reducing (ADP-ribose, IDP-ribose) and non-reducing NDP-sugars (ADP-glucose, ADP-mannose, GDP-mannose, UDP-mannose, UDP-glucose, UDP-xylose, CDP-glucose), CDP-alcohols (CDP-glycerol, CDP-ethanolamine, CDP-choline), dinucleotides (diadenosine pyrophosphate, NADH, NAD + , FAD), nucleoside(5′) mono- and diphosphates (AMP, CMP, GMP, ADP, CDP) and dTMP p -nitrophenyl ester. Since the enzymes have not been purified to homogeneity, more than three Pyrophosphatases may be present, but the co-purification of activities, thermal co-inactivation, and inhibition experiments give support to: (i) an ADP-ribose Pyrophosphatase highly specific for ADP(IDP)-ribose in the presence of Mg 2+ , but active also on non-reducing ADP-hexoses and dinucleotides (not on NAD + ) when Mg 2+ was replaced with Mn 2+ ; (ii) a Mn 2+ -dependent Pyrophosphatase active on ADP(IDP)-ribose, dinucleotides and CDP-alcohols; (iii) a rather unspecific Pyrophosphatase that, with Mg 2+ , was active on AMP(IMP)-containing NDP-sugars and dinucleotides (not on NAD + ), and with Mn 2+ , was also active on non-adenine NDP-sugars and CDP-alcohols. The enzymes differ from nucleotide Pyrophosphatase/phosphodiesterase-I (NPPase/PDEaseI) by their substrate specificities and by their cytosolic location and solubility in the absence of detergents. Although NPPase/PDEaseI is much more active in rat liver, its known location in the non-cytoplasmic sides of plasma and endoplasmic reticulum membranes, together with the known cytoplasmic synthesis of NDP-sugars and CDP-alcohols, permit the speculation that the Pyrophosphatases studied in this work may have a cellular role.
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Rat liver nucleoside diphosphosugar or diphosphoalcohol Pyrophosphatases different from nucleotide Pyrophosphatase or phosphodiesterase I: substrate specificities of Mg2+- and/or Mn2+-dependent hydrolases acting on ADP-ribose☆
Biochimica et biophysica acta, 1995Co-Authors: Jose Canales, Rosa Maria Pinto, Maria Jesus Costas, Asuncion Miro, Diego Bernet, Ascension Fernandez, María Teresa Hernández, Jose Carlos CameselleAbstract:Abstract Three rat liver nucleoside(5′) diphosphosugar (NDP-sugar) or nucleoside(5′) diphosphoalcohol Pyrophosphatases are described: two were previously identified in experiments measuring Mg 2+ -dependent ADP-ribose Pyrophosphatase activity (Miro et al. (1989) FEBS Lett. 244, 123–126), and the other is a new, Mn 2+ -dependent ADP-ribose Pyrophosphatase. They are resolved by ion-exchange chromatography, and differ by their substrate and cation specificities, K M values for ADP-ribose, pH-activity profiles, molecular weights and isoelectric points. The enzymes were tested for activity towards: reducing (ADP-ribose, IDP-ribose) and non-reducing NDP-sugars (ADP-glucose, ADP-mannose, GDP-mannose, UDP-mannose, UDP-glucose, UDP-xylose, CDP-glucose), CDP-alcohols (CDP-glycerol, CDP-ethanolamine, CDP-choline), dinucleotides (diadenosine pyrophosphate, NADH, NAD + , FAD), nucleoside(5′) mono- and diphosphates (AMP, CMP, GMP, ADP, CDP) and dTMP p -nitrophenyl ester. Since the enzymes have not been purified to homogeneity, more than three Pyrophosphatases may be present, but the co-purification of activities, thermal co-inactivation, and inhibition experiments give support to: (i) an ADP-ribose Pyrophosphatase highly specific for ADP(IDP)-ribose in the presence of Mg 2+ , but active also on non-reducing ADP-hexoses and dinucleotides (not on NAD + ) when Mg 2+ was replaced with Mn 2+ ; (ii) a Mn 2+ -dependent Pyrophosphatase active on ADP(IDP)-ribose, dinucleotides and CDP-alcohols; (iii) a rather unspecific Pyrophosphatase that, with Mg 2+ , was active on AMP(IMP)-containing NDP-sugars and dinucleotides (not on NAD + ), and with Mn 2+ , was also active on non-adenine NDP-sugars and CDP-alcohols. The enzymes differ from nucleotide Pyrophosphatase/phosphodiesterase-I (NPPase/PDEaseI) by their substrate specificities and by their cytosolic location and solubility in the absence of detergents. Although NPPase/PDEaseI is much more active in rat liver, its known location in the non-cytoplasmic sides of plasma and endoplasmic reticulum membranes, together with the known cytoplasmic synthesis of NDP-sugars and CDP-alcohols, permit the speculation that the Pyrophosphatases studied in this work may have a cellular role.
S. J. Crafts-brandner - One of the best experts on this subject based on the ideXlab platform.
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Purification and Properties of a Unique Nucleotide Pyrophosphatase/Phosphodiesterase I That Accumulates in Soybean Leaves in Response to Fruit Removal
Plant Physiology, 1995Co-Authors: Michael E. Salvucci, S. J. Crafts-brandnerAbstract:Several unique proteins accumulate in soybean (Glycine max) leaves when the developing fruits are removed. In the present study, elevated levels of nucleotide Pyrophosphatase and phosphodiesterase I activities were present in leaves of defruited soybean plants. The soluble enzyme catalyzing these reactions was purified nearly 1000-fold, producing a preparation that contained a single 72-kD polypeptide. The molecular mass of the holoenzyme was approximately 560 kD, indicating that the native enzyme was likely octameric. The purified enzyme hydrolyzed nucleotide-sugars, nucleotide di- and triphosphates, thymidine monophosphate p-nitrophenol, and inorganic pyrophosphate but not nucleotide monophosphates, sugar mono- and bisphosphates, or NADH. The subunit and holoenzyme molecular masses and the preference for substrates distinguish the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I from other plant nucleotide Pyrophosphatase/phosphodiesterase I enzymes. Also, the N-terminal sequence of the soybean leaf enzyme exhibited no similarity to the mammalian nucleotide Pyrophosphatase/phosphodiesterase I, soybean vegetative storage proteins, or other entries in the data bank. Thus, the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I appears to be a heretofore undescribed protein that is physically and enzymatically distinct from nucleotide Pyrophosphatase/phosphodiesterase I from other sources, as well as from other phosphohydrolytic enzymes that accumulate in soybean leaves in response to fruit removal.
S J Craftsbrandner - One of the best experts on this subject based on the ideXlab platform.
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purification and properties of a unique nucleotide Pyrophosphatase phosphodiesterase i that accumulates in soybean leaves in response to fruit removal
Plant Physiology, 1995Co-Authors: Michael E. Salvucci, S J CraftsbrandnerAbstract:Several unique proteins accumulate in soybean (Glycine max) leaves when the developing fruits are removed. In the present study, elevated levels of nucleotide Pyrophosphatase and phosphodiesterase I activities were present in leaves of defruited soybean plants. The soluble enzyme catalyzing these reactions was purified nearly 1000-fold, producing a preparation that contained a single 72-kD polypeptide. The molecular mass of the holoenzyme was approximately 560 kD, indicating that the native enzyme was likely octameric. The purified enzyme hydrolyzed nucleotide-sugars, nucleotide di- and triphosphates, thymidine monophosphate p-nitrophenol, and inorganic pyrophosphate but not nucleotide monophosphates, sugar mono- and bisphosphates, or NADH. The subunit and holoenzyme molecular masses and the preference for substrates distinguish the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I from other plant nucleotide Pyrophosphatase/phosphodiesterase I enzymes. Also, the N-terminal sequence of the soybean leaf enzyme exhibited no similarity to the mammalian nucleotide Pyrophosphatase/phosphodiesterase I, soybean vegetative storage proteins, or other entries in the data bank. Thus, the soybean leaf nucleotide Pyrophosphatase/phosphodiesterase I appears to be a heretofore undescribed protein that is physically and enzymatically distinct from nucleotide Pyrophosphatase/phosphodiesterase I from other sources, as well as from other phosphohydrolytic enzymes that accumulate in soybean leaves in response to fruit removal.
