Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Target Concepts:
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Query: EC:3.1.4.1 (
phosphodiesterase
)
18,767
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Fluoride acts as a noncompetitive, strong inhibitor of (asymmetrical) Ap4A hydrolases (EC 3.6.1.17). The Ki values estimated for the enzymes isolated from seeds of some higher plants (yellow lupin, sunflower and marrow) are in the range of 2-3 microM and I50 for the hydrolase from a mammalian tissue (beef liver) is 20 microM. The anion, up to 25 mM, does not affect the following other enzymes which are able to degrade the bis(5'-nucleosidyl)-oligophosphates: Escherichia coli (symmetrical)
Ap4A hydrolase
(
EC 3.6.1.41
), yeast Ap4A phosphorylase (EC 2.7.7.53), yellow lupin Ap3A hydrolase (EC 3.6.1.29) and
phosphodiesterase
(
EC 3.1.4.1
). None of halogenic anions but fluoride affects the activity of (asymmetrical) Ap4A hydrolases. Usefulness of the fluoride effect for the in vivo studies on the Ap4A metabolism is shortly discussed.
...
PMID:Fluoride is a strong and specific inhibitor of (asymmetrical) Ap4A hydrolases. 215 11
The substrate specificity of procaryotic and eucaryotic AppppA-degrading enzymes was investigated with phosphonate analogues of diadenosine 5',5'''-P1,P4-tetraphosphate (AppppA). App(CH2)ppA (I), App(CHBr)ppA (II), and Appp(CH2)pA (III), but not Ap(CH2)pp(CH2)pA (IV), are substrates for lupin AppppA hydrolase (EC 3.6.1.17) and
phosphodiesterase I
(
EC 3.1.4.1
). None of the four analogues is hydrolyzed by bacterial AppppA hydrolase (
EC 3.6.1.41
), and only analogue III is degraded by yeast AppppA phosphorylase (EC 2.7.7.53). The analogues are competitive inhibitors of all four enzymes. The affinity of analogue IV is 3-40-fold lower than that of analogues I-III for all four enzymes. Introduction of one methylene (as in I and III) [or bromomethylene (as in II)] group into AppppA results in a 3-15-fold increase of its affinity for lupin and Escherichia coli AppppA hydrolases. The same modifications only negligibly (10-30%) affect its affinity for yeast AppppA phosphorylase and decrease its affinity for lupin
phosphodiesterase I
about 2.5-fold. The data provide further evidence for the heterogeneity among catalytic sites of all four AppppA-degrading enzymes.
...
PMID:Phosphonate analogues of diadenosine 5',5'''-P1,P4-tetraphosphate as substrates or inhibitors of procaryotic and eucaryotic enzymes degrading dinucleoside tetraphosphates. 282 Apr 68
A hydrolase activity directed against diadenosine 5',5"'-P1, P4-tetraphosphate (Ap4A) has been solubilised and partially purified from the plasma membrane fraction of bovine adrenal medullary chromaffin tissue in order to determine its relationship to
alkaline phosphodiesterase
-I/nucleotide pyrophosphatase (PDase-I,
EC 3.1.4.1
). Activity with the specific dinucleoside tetraphosphatase (EC 3.6.1. 17) substrate Ap4A and with the non-specific PDase-I substrate thymidine 5'-monophosphate p-nitrophenyl ester had Km and Vmax values of 2.0 microM and 600 pmol/min/mg protein and 0.2 mM and 26 nmol/min/mg protein respectively and co-chromatographed upon gel filtration and ion-exchange chromatography. Activity with the fluorescent substrates etheno-Ap4A and 4-methylumbelliferyl phenylphosphonate co-electrophoresed on native polyacrylamide gels. No activity was detected which exclusively hydrolysed Ap4A. Immunoblotting of the most purified fraction with an antibody against mouse PC-1, one of the major PDase-I family members, detected bands of 240, 120 and 62 kDa corresponding to PC-1 dimer, monomer and proteolytic fragment. Therefore, the activity previously described as bovine adrenal chromaffin cell ecto(
diadenosine polyphosphate hydrolase
) (ecto-ApnAase) is a PDase-I, probably bovine PC-1.
...
PMID:The hydrolytic activity of bovine adrenal medullary plasma membranes towards diadenosine polyphosphates is due to alkaline phosphodiesterase-I. 978 21
