Bibliografías temáticas / Phosphoesterase

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Literatura académica sobre el tema "Phosphoesterase"

Autor: Grafiati
Publicado: 4 de junio de 2021
Última modificación: 19 de febrero de 2023

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Artículos de revistas sobre el tema "Phosphoesterase"

1

Ogden, Kristen M., Liya Hu, Babal K. Jha, Banumathi Sankaran, Susan R. Weiss, Robert H. Silverman, John T. Patton y B. V. Venkataram Prasad. "Structural Basis for 2′-5′-Oligoadenylate Binding and Enzyme Activity of a Viral RNase L Antagonist". Journal of Virology 89, n.º 13 (15 de abril de 2015): 6633–45. http://dx.doi.org/10.1128/jvi.00701-15.

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ABSTRACTSynthesis of 2′-5′-oligoadenylates (2-5A) by oligoadenylate synthetase (OAS) is an important innate cellular response that limits viral replication by activating the latent cellular RNase, RNase L, to degrade single-stranded RNA. Some rotaviruses and coronaviruses antagonize the OAS/RNase L pathway through the activity of an encoded 2H phosphoesterase domain that cleaves 2-5A. These viral 2H phosphoesterases are phylogenetically related to the cellular A kinase anchoring protein 7 (AKAP7) and share a core structure and an active site that contains two well-defined HΦ(S/T)Φ (where Φ is a hydrophobic residue) motifs, but their mechanism of substrate binding is unknown. Here, we report the structures of a viral 2H phosphoesterase, the C-terminal domain (CTD) of the group A rotavirus (RVA) VP3 protein, both alone and in complex with 2-5A. The domain forms a compact fold, with a concave β-sheet that contains the catalytic cleft, but it lacks two α-helical regions and two β-strands observed in AKAP7 and other 2H phosphoesterases. The cocrystal structure shows significant conformational changes in the R loop upon ligand binding. Bioinformatics and biochemical analyses reveal that conserved residues and residues required for catalytic activity and substrate binding comprise the catalytic motifs and a region on one side of the binding cleft. We demonstrate that the VP3 CTD of group B rotavirus, but not that of group G, cleaves 2-5A. These findings suggest that the VP3 CTD is a streamlined version of a 2H phosphoesterase with a ligand-binding mechanism that is shared among 2H phosphodiesterases that cleave 2-5A.IMPORTANCEThe C-terminal domain (CTD) of rotavirus VP3 is a 2H phosphoesterase that cleaves 2′-5′-oligoadenylates (2-5A), potent activators of an important innate cellular antiviral pathway. 2H phosphoesterase superfamily proteins contain two conserved catalytic motifs and a proposed core structure. Here, we present structures of a viral 2H phosphoesterase, the rotavirus VP3 CTD, alone and in complex with its substrate, 2-5A. The domain lacks two α-helical regions and β-strands present in other 2H phosphoesterases. A loop of the protein undergoes significant structural changes upon substrate binding. Together with our bioinformatics and biochemical findings, the crystal structures suggest that the RVA VP3 CTD domain is a streamlined version of a cellular enzyme that shares a ligand-binding mechanism with other 2H phosphodiesterases that cleave 2-5A but differs from those of 2H phosphodiesterases that cleave other substrates. These findings may aid in the future design of antivirals targeting viral phosphodiesterases with cleavage specificity for 2-5A.
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Yin, Yue, David Frank, Weijie Zhou, Neena Kaur, Jarrod B. French y Nick Carpino. "An unexpected 2-histidine phosphoesterase activity of suppressor of T-cell receptor signaling protein 1 contributes to the suppression of cell signaling". Journal of Biological Chemistry 295, n.º 25 (5 de mayo de 2020): 8514–23. http://dx.doi.org/10.1074/jbc.ra120.013482.

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The suppressor of T-cell receptor (TCR) signaling (Sts) proteins Sts-1 and Sts-2 suppress receptor-mediated signaling pathways in various immune cells, including the TCR pathway in T cells and the Dectin-1 signaling pathway in phagocytes. As multidomain enzymes, they contain an N-terminal ubiquitin-association domain, a central Src homology 3 domain, and a C-terminal histidine phosphatase domain. Recently, a 2-histidine (2H) phosphoesterase motif was identified within the N-terminal portion of Sts. The 2H phosphoesterase motif defines an evolutionarily ancient protein domain present in several enzymes that hydrolyze cyclic phosphate bonds on different substrates, including cyclic nucleotides. It is characterized by two invariant histidine residues that play a critical role in catalytic activity. Consistent with its assignment as a phosphoesterase, we demonstrate here that the Sts-1 2H phosphoesterase domain displays catalytic, saturable phosphodiesterase activity toward the dinucleotide 2′,3′-cyclic NADP. The enzyme exhibited a high degree of substrate specificity and selectively generated the 3′-nucleotide as the sole product. Sts-1 also had phosphodiesterase catalytic activity toward a 5-mer RNA oligonucleotide containing a 2′,3′-cyclic phosphate group at its 3′ terminus. To investigate the functional significance of Sts-1 2H phosphoesterase activity, we generated His-to-Ala variants and examined their ability to negatively regulate cellular signaling pathways. Substitution of either conserved histidine compromised the ability of Sts-1 to suppress signaling pathways downstream of both the TCR and the Dectin-1 receptor. Our results identify a heretofore unknown cellular enzyme activity associated with Sts-1 and indicate that this catalytic activity is linked to specific cell-signaling outcomes.
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Katz, Michael J., Su-Young Moon, Joseph E. Mondloch, M. Hassan Beyzavi, Casey J. Stephenson, Joseph T. Hupp y Omar K. Farha. "Exploiting parameter space in MOFs: a 20-fold enhancement of phosphate-ester hydrolysis with UiO-66-NH2". Chemical Science 6, n.º 4 (2015): 2286–91. http://dx.doi.org/10.1039/c4sc03613a.

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Using the enzymatic mechanism of phosphoesterase as a template, we were able to modify a metal–organic framework such that the hydrolysis rates were 50 times faster than previously demonstrated with UiO-66.
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Han, Gye Won, Jaeju Ko, Carol L. Farr, Marc C. Deller, Qingping Xu, Hsiu-Ju Chiu, Mitchell D. Miller et al. "Crystal structure of a metal-dependent phosphoesterase (YP_910028.1) from Bifidobacterium adolescentis: Computational prediction and experimental validation of phosphoesterase activity". Proteins: Structure, Function, and Bioinformatics 79, n.º 7 (2 de mayo de 2011): 2146–60. http://dx.doi.org/10.1002/prot.23035.

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Li, Xiao-Yu. "Clinical application of phosphoesterase complex in liver diseases". World Chinese Journal of Digestology 22, n.º 29 (2014): 4424. http://dx.doi.org/10.11569/wcjd.v22.i29.4424.

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Gold, Matthew G., F. Donelson Smith, John D. Scott y David Barford. "AKAP18 Contains a Phosphoesterase Domain that Binds AMP". Journal of Molecular Biology 375, n.º 5 (febrero de 2008): 1329–43. http://dx.doi.org/10.1016/j.jmb.2007.11.037.

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Bressan, Debra A., Heidi A. Olivares, Benjamin E. Nelms y John H. J. Petrini. "Alteration of N-Terminal Phosphoesterase Signature Motifs Inactivates Saccharomyces cerevisiae Mre11". Genetics 150, n.º 2 (1 de octubre de 1998): 591–600. http://dx.doi.org/10.1093/genetics/150.2.591.

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Abstract Saccharomyces cerevisiae Mre11, Rad50, and Xrs2 function in a protein complex that is important for nonhomologous recombination. Null mutants of MRE11, RAD50, and XRS2 are characterized by ionizing radiation sensitivity and mitotic interhomologue hyperrecombination. We mutagenized the four highly conserved phosphoesterase signature motifs of Mre11 to create mre11-11, mre11-2, mre11-3, and mre11-4 and assessed the functional consequences of these mutant alleles with respect to mitotic interhomologue recombination, chromosome loss, ionizing radiation sensitivity, double-strand break repair, and protein interaction. We found that mre11 mutants that behaved as the null were sensitive to ionizing radiation and deficient in double-strand break repair. We also observed that these null mutants exhibited a hyperrecombination phenotype in mitotic cells, consistent with previous reports, but did not exhibit an increased frequency of chromosome loss. Differential ionizing radiation sensitivities among the hypomorphic mre11 alleles correlated with the trends observed in the other phenotypes examined. Two-hybrid interaction testing showed that all but one of the mre11 mutations disrupted the Mre11-Rad50 interaction. Mutagenesis of the phosphoesterase signatures in Mre11 thus demonstrated the importance of these conserved motifs for recombinational DNA repair.
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Aravind, L. y E. V. Koonin. "Phosphoesterase domains associated with DNA polymerases of diverse origins". Nucleic Acids Research 26, n.º 16 (1 de agosto de 1998): 3746–52. http://dx.doi.org/10.1093/nar/26.16.3746.

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9

Quist, Eugene. "Ca2+-stimulated phospholipid phosphoesterase activities in rabbit erythrocyte membranes". Archives of Biochemistry and Biophysics 236, n.º 1 (enero de 1985): 140–49. http://dx.doi.org/10.1016/0003-9861(85)90613-7.

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10

Breaker, Ronald R. y Gerald F. Joyce. "A DNA enzyme with Mg2+-dependent RNA phosphoesterase activity". Chemistry & Biology 2, n.º 10 (octubre de 1995): 655–60. http://dx.doi.org/10.1016/1074-5521(95)90028-4.

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Tesis sobre el tema "Phosphoesterase"

1

Daver, Henrik. "Quantum Chemical Modeling of Phosphoesterase Mimics and Chemistry in Confined Spaces". Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-148259.

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In this thesis, density functional theory is employed in the study of two kinds of systems that can be considered to be biomimetic in their own ways. First, three binuclear metal complexes, synthesized by the group of Prof. Ebbe Nordlander, have been investigated. The complexes are designed to resemble the active sites of phosphatase enzymes and have been examined in complexes where either two Zn(II) ions or one Fe(III) and one Mn(II) ion are bound. These dinuclear compounds were studied as catalysts for the hydrolysis of bis(2,4-dinitrophenyl) phosphate and the transesterification of 2-hydroxypropyl p-nitrophenyl phosphate, which are model systems for the same reactions occurring in DNA or RNA. It was found that the two reactions take place in similar ways: a hydroxide ion that is terminally bound to one of the metal centers acts either as a nucleophile in the hydrolysis reaction or as a base in the transesterification. The leaving groups depart in an effectively concerted manner, and the formed catalyst-product complexes are predicted to be the resting states of the catalytic cycles. The rate-determining free energy barriers are identified from the catalyst-product complex in one catalytic cycle to the transition state of nucleophilic attack in the next. Another type of biomimetic modeling is made with an aim of imitating the conceptual features of selective binding of guests and screening them from solute-solvent interactions. Such features are found in so-called nanocontainers, and this thesis is concerned with studies of two capsules synthesized by the group of Prof. Julius Rebek, Jr. First, the cycloaddition of phenyl acetylene and phenyl azide has experimentally been observed to be accelerated in the presence of a capsule. Computational studies were herein performed on this system, and a previously unrecognized structure of the capsule is discovered. Two main factors are then identified as sources of the rate acceleration compared to the uncatalyzed reaction, namely the reduction of the entropic component and the selective destabilization of the reactant supercomplex over the transition state. In the second capsule study, the alkane binding trends of a water-soluble cavitand was studied. It is found that implicit solvation models fail severely in reproducing the experimental equilibrium observed between binding of n-decane by the cavitand monomer and encapsulation in the capsule dimer. A mixed explicit/implicit solvation protocol is developed to better quantify the effect of hydrating the cavitand, and a simple correction to the hydration free energy of a single water molecule is proposed to remedy this. The resulting scheme is used to predict new hydration free energies of the cavitand complexes, resulting in significant improvement vis-à-vis experiments. The computational results presented in this thesis show the usefulness of the quantum chemical calculations to develop understanding of experimental trends observed for substrate binding and catalysis. In particular, the methodology is shown to be versatile enough such that experimental observations can be reproduced for such diverse systems as studied herein.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 5: Manuscript.

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McMillen, Lyle y l. mcmillen@sct gu edu au. "Isolation and Characterisation of the 5'-Nucleotidase from Escherichia coli". Griffith University. School of Biomolecular and Biomedical Science, 2001. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030226.153545.

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Escherichia coli 5'-nucleotidase is a periplasmically localised enzyme capable of hydrolysing a broad range of substrates, including all 5'-ribo- and 5'-deoxyribonucleotides, uridine diphosphate sugars, and a number of synthetic substrates such as bis (r-nitrophenyl) phosphate. The enzyme has been shown to contain at least one zinc ion following purification, and to have two metal binding sites in the catalytic cleft. 5'-Nucleotidase activity is significantly stimulated by the addition of particular divalent metal ions, most notably cobalt which results in a 30-50 fold increase in activity. Significant sequence homology between the E. coli 5'-nucleotidase and members of the Ser/Thr protein phosphatase family in the catalytic site has lead to 5'-nucleotidase being included in this protein family. This thesis describes the development of a rapid purification methodology for milligram quantities of 5'-nucleotidase, and the investigation of a number of physical and biochemical properties of the enzyme with the aim of comparing these properties to those of certain catalytic site mutants. The molecular weight of the mature protein was estimated as 58219 daltons, with a specific activity for 5'-AMP, in the presence of 4 mM Co2+ and 13 mM Ca2+ at pH 6.0, of 730 mmol/min/mg. The presence of up to two zinc ions associated with the purified enzyme was observed using ICP-ES analysis, suggesting both metal ion binding sites are occupied by zinc in vivo, and some degree of displacement of zinc by cobalt could be observed. Mass spectrometry data, gathered at 60 and 70 mS orifice potential, suggested the presence of a small proportion of material with a mass 118 to 130 daltons greater than the main 5'-nucleotidase mass estimation. This study suggests that this mass difference, only evident at the lower orificepotential, is due to the presence of two zinc ions closely associated with 5'-nucleotidase. To account for the observed high level of activation of 5'-nucleotidase activity by particular divalent metal ions, this thesis describes a proposed model in which these divalent ions may displace the zinc ion at one of the metal ion binding sites. This displacement only occurs at one of the two metal ion binding sites, with the other metal binding site retaining the zinc ion already present. Studies with purified enzyme, each with a single amino acid substitution, lend support to this hypothesis and suggest the identity of the metal ion binding site at which displacement occurs. Seven key catalytic site residues (Asp-41, His-43, Asp-84, His-117, Glu-118, His-217 and His-252) were selected on the basis of sequence conservation within the Ser/Thr protein phosphatases and 5'-nucleotidases. X-ray crystallographic data published by others during this study implicated five of the selected residues (Asp-41, His-43, Asp-84, His-217 and His-252) directly in metal ion binding, including two residues from each metal ion binding site and one directly involved in both sites (Asp-84). The remaining two residues (His-117 and Glu-118) are highly conserved but were not thought to play direct roles in metal ion binding. The seven selected residues were modified by site-directed mutagenesis, and the effect of the amino acid substitutions upon the kinetic properties of 5'-nucleotidase activity was determined. Residues hypothesised to be involved in metal ion displacement, and subsequent activation of 5'-nucleotidase activity, were identified by reductions in metal ion affinity and increased levels of activation by cobalt compared to the wild type 5'-nucleotidase. This study suggests that the metal binding site, M2, that includes residues Asp-84, His-217 and His-252, is involved in metal ion displacement, while the other metal binding site, M1, is not. This, in turn, suggests the metal binding sites are functionally non-equivalent and kinetically distinct. No residues were identified in this study as playing significant roles in substrate binding, as there was no significant reduction observed in affinity for 5'-AMP observed in any of the catalytic site mutants.
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3

McMillen, Lyle. "Isolation and Characterisation of the 5'-Nucleotidase from Escherichia coli". Thesis, Griffith University, 2001. http://hdl.handle.net/10072/366487.

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Escherichia coli 5'-nucleotidase is a periplasmically localised enzyme capable of hydrolysing a broad range of substrates, including all 5'-ribo- and 5'-deoxyribonucleotides, uridine diphosphate sugars, and a number of synthetic substrates such as bis (r-nitrophenyl) phosphate. The enzyme has been shown to contain at least one zinc ion following purification, and to have two metal binding sites in the catalytic cleft. 5'-Nucleotidase activity is significantly stimulated by the addition of particular divalent metal ions, most notably cobalt which results in a 30-50 fold increase in activity. Significant sequence homology between the E. coli 5'-nucleotidase and members of the Ser/Thr protein phosphatase family in the catalytic site has lead to 5'-nucleotidase being included in this protein family. This thesis describes the development of a rapid purification methodology for milligram quantities of 5'-nucleotidase, and the investigation of a number of physical and biochemical properties of the enzyme with the aim of comparing these properties to those of certain catalytic site mutants. The molecular weight of the mature protein was estimated as 58219 daltons, with a specific activity for 5'-AMP, in the presence of 4 mM Co2+ and 13 mM Ca2+ at pH 6.0, of 730 mmol/min/mg. The presence of up to two zinc ions associated with the purified enzyme was observed using ICP-ES analysis, suggesting both metal ion binding sites are occupied by zinc in vivo, and some degree of displacement of zinc by cobalt could be observed. Mass spectrometry data, gathered at 60 and 70 mS orifice potential, suggested the presence of a small proportion of material with a mass 118 to 130 daltons greater than the main 5'-nucleotidase mass estimation. This study suggests that this mass difference, only evident at the lower orificepotential, is due to the presence of two zinc ions closely associated with 5'-nucleotidase. To account for the observed high level of activation of 5'-nucleotidase activity by particular divalent metal ions, this thesis describes a proposed model in which these divalent ions may displace the zinc ion at one of the metal ion binding sites. This displacement only occurs at one of the two metal ion binding sites, with the other metal binding site retaining the zinc ion already present. Studies with purified enzyme, each with a single amino acid substitution, lend support to this hypothesis and suggest the identity of the metal ion binding site at which displacement occurs. Seven key catalytic site residues (Asp-41, His-43, Asp-84, His-117, Glu-118, His-217 and His-252) were selected on the basis of sequence conservation within the Ser/Thr protein phosphatases and 5'-nucleotidases. X-ray crystallographic data published by others during this study implicated five of the selected residues (Asp-41, His-43, Asp-84, His-217 and His-252) directly in metal ion binding, including two residues from each metal ion binding site and one directly involved in both sites (Asp-84). The remaining two residues (His-117 and Glu-118) are highly conserved but were not thought to play direct roles in metal ion binding. The seven selected residues were modified by site-directed mutagenesis, and the effect of the amino acid substitutions upon the kinetic properties of 5'-nucleotidase activity was determined. Residues hypothesised to be involved in metal ion displacement, and subsequent activation of 5'-nucleotidase activity, were identified by reductions in metal ion affinity and increased levels of activation by cobalt compared to the wild type 5'-nucleotidase. This study suggests that the metal binding site, M2, that includes residues Asp-84, His-217 and His-252, is involved in metal ion displacement, while the other metal binding site, M1, is not. This, in turn, suggests the metal binding sites are functionally non-equivalent and kinetically distinct. No residues were identified in this study as playing significant roles in substrate binding, as there was no significant reduction observed in affinity for 5'-AMP observed in any of the catalytic site mutants.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Biomedical Sciences
Science, Environment, Engineering and Technology
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4

Gusho, Elona. "AKAP7 Degrades 2-5A Mediators of the Interferon Antiviral Response". Cleveland State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=csu1449496406.

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5

Awal, Sushil. "Targeting ubiquitin receptor protein UBASH3B for future cancer therapies". Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAJ094.

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Des anomalies dans la ségrégation des chromosomes pendant la mitose entraînent une aneuploïdie ou une polyploïdie. La protéine UBASH3B, une protéine de liaison à l’ubiquitine, joue un rôle crucial dans la transmission de l’Aurora B aux microtubules avant l’apparition de l’anaphase pour une ségrégation chromosomique appropriée. Nous avons effectué un dépistage à haut débit pour cribler un nouvel inhibiteur de l’UBASH3B à petite molécule, le FD-E09, à l’aide de la protéine recombinante UBASH3. Le traitement par l’inhibiteur de l’UBASH3B a entraîné la propagation d’Aurora B sur les chromosomes pendant la prométaphase, affectant ainsi le moment et la fidélité de la mitose. Il affecte également le complexe UBASH3B-Aurora B-Mklp2. Mes données décrit également que le domaine 2 Histidine phosphoesterase dans UBASH3B entre le domaine UBA et SH3 joue un rôle dans la localisation correcte d’Aurora B, la progression mitotique, ainsi que l’interaction avec Aurora B et Mklp2. Nous avons également criblé les lignées cellulaires cancéreuses qui réagissent à l’inhibition de l’UBASH3B. Par conséquent, nos résultats découvrent l’inhibiteur de la petite molécule UBASH3B qui pourrait cibler l’UBASH3B pour traiter des cellules cancéreuses spécifiques et également découvrir le domaine de la phosphoésterase 2H nouvellement identifié dans UBASH3B qui régule la localisation d’Aurora B en mitose
Defects in proper segregation of chromosomes during mitosis result in aneuploidy or polyploidy. UBASH3B protein, a ubiquitin-binding protein, plays a crucial role in driving Aurora B to microtubules before anaphase onset for proper chromosome segregation. We here performed a high-throughput screening to screen out a novel small-molecule UBASH3B inhibitor, FD-E09 using recombinant UBASH3 protein. Treatment with UBASH3B inhibitor led to the spreading of Aurora B to chromosomal arms during prometaphase, thus affecting the timing and fidelity of mitosis. It also affects the UBASH3B-Aurora B-MKlp2 complex. My data also unfold the 2 Histidine phosphoesterase domain in UBASH3B between UBA and SH3 domain that plays a role in proper localization of Aurora B, mitotic progression, as well as interaction with Aurora B and MKlp2. We also screened out the cancer cell lines that are responsive to the UBASH3B inhibition. Hence, our findings uncover the small-molecule UBASH3B inhibitor that could target UBASH3B to treat specific cancer cells and also uncover newly identified 2H phosphoesterase domain in UBASH3B that regulates Aurora B localization in mitosis
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Duboc-Toia, Carole. "Réactivité chimique des complexes dinucléaires de fer (III) à pont oxo : applications en catalyse d'oxydation énantiosélective et en hydrolyse de phosphoesters". Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10092.

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Modeliser le site actif d'une metalloenzyme est une approche indispensable a la caracterisation precise de son site metallique et a la comprehension de son mecanisme d'action. Au laboratoire, nous nous sommes plus particulierement interesses a deux enzymes la methane monooxygenase (mmo) et la phosphatase acide pourpre (pap) issues de la classe des proteines a fer oxo, enzymes contenant toutes au sein de leur site actif un systeme dinucleaire de fer (iii) ponte par un oxygene. Leurs activites catalytiques, oxydation d'alcanes pour la mmo et hydrolyse de phosphoesters pour la pap, ont ete reproduites a l'aide de nouveaux complexes dinucleaires de fer (iii) a pont oxo. Dans le cas de la catalyse d'oxydation d'alcanes, notre premier objectif a ete d'optimiser les premiers complexes synthetises au laboratoire. Pour se faire, la stabilite des complexes a ete amelioree et des conditions d'oxydation efficaces ont ete mises au point en utilisant le peroxyde d'hydrogene comme oxydant. Quant a leur mecanisme d'action, l'introduction d'elements de chiralite au sein des complexes a permis d'effectuer des hydroxylations enantioselectives, demontrant ainsi que la reaction est centree sur le metal. L'ensemble des resultats ainsi que la caracterisation d'un intermediaire, un complexe dinucleaire de fer (iii) -oxo -peroxo a permis de proposer un mecanisme d'action qui est proche de celui propose pour la mmo. Ces complexes optiquement actifs se sont aussi reveles etre de bons catalyseurs d'oxydation de sulfures. Ils sont chimiospecifiques puisque seul le sulfoxyde est forme et les reactions sont enantioselectives. Le mecanisme d'action a ete entierement elucide grace a des etudes cinetiques alliees a des etudes spectroscopiques. Pour la premiere fois, la reactivite d'un systeme peroxo ferrique a ete mise en evidence. Enfin, nous avons etudie les proprietes acido-basiques d'un de ces complexes dans l'eau. Ceci a conduit a la synthese du premier complexe dinucleaire de fer (iii) a pont -oxo possedant deux ligands hydroxo stables aussi bien a l'etat solide qu'en solution. Son acide conjugue s'est revele efficace en hydrolyse de phosphodiesters. L'etude du mecanisme a mis en evidence le role essentiel d'un ligand hydroxo et l'importance de la structure dinucleaire du systeme qui permet une synergie entre les deux sites metalliques. Ce systeme chimique represente le premier modele a la fois structural et fonctionnel de l'enzyme et sa reactivite valide le mecanisme d'action propose pour la pap.
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Capítulos de libros sobre el tema "Phosphoesterase"

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Daumann, Lena Josefine. "Structural and Mechanistic Studies of Zn(II) Complexes as Phosphoesterase Models". En Spectroscopic and Mechanistic Studies of Dinuclear Metallohydrolases and Their Biomimetic Complexes, 89–117. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-06629-5_4.

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Daumann, Lena Josefine. "Mechanistic Studies of Cd(II) Complexes as Phosphoesterase and Metallo-β-lactamase Models". En Spectroscopic and Mechanistic Studies of Dinuclear Metallohydrolases and Their Biomimetic Complexes, 119–43. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-06629-5_5.

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Daumann, Lena Josefine. "Spectroscopic and Mechanistic Studies of Co(II) Phosphoesterase and Metallo-β-lactamase Biomimetics". En Spectroscopic and Mechanistic Studies of Dinuclear Metallohydrolases and Their Biomimetic Complexes, 145–88. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-06629-5_6.

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Tole, Philip y Carmay Lim. "Do Stereoelectronic Effects Control the Structure and Reactivity of Trigonal-Bipyramidal Phosphoesters?" En ACS Symposium Series, 240–55. Washington, DC: American Chemical Society, 1993. http://dx.doi.org/10.1021/bk-1993-0539.ch013.

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Krämer, Roland y Tamás Gajda. "Functional model complexes for dinuclear phosphoesterase enzymes". En Perspectives on Bioinorganic Chemistry, 209–40. Elsevier, 1999. http://dx.doi.org/10.1016/s1062-239x(99)80032-7.

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Informes sobre el tema "Phosphoesterase"

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Chin, Jik. Artificial Metallo-Phosphoesterase. Fort Belvoir, VA: Defense Technical Information Center, mayo de 2001. http://dx.doi.org/10.21236/ada394524.

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Chin, Jik. Artificial Phosphoesterase: Metal Activation by Strain. Fort Belvoir, VA: Defense Technical Information Center, junio de 1993. http://dx.doi.org/10.21236/ada271367.

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