Gene/Protein Disease Symptom Drug Enzyme Compound
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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)

Rat liver and brain differ in the distribution pattern of the total hydrolytic activity on diadenosine 5',5"'-P1,P3-triphosphate (Ap3A) between the soluble and particulate fractions. The Ap3A-hydrolase activity in both the soluble and particulate liver fractions and in the brain soluble fraction had been previously studied in detail. We report now on the brain particulate fraction which, unlike liver, showed a low unspecific phosphodiesterase I-like (PDEaseI, EC 3.1.4.1) activity relative to the specific dinucleoside triphosphatase (Ap3Aase, EC 3.6.1.29). Two PDEaseI-like forms (PDEaseI-A and PDEaseI-B), with different apparent Mrs and kinetic properties, and two Ap3Aases (Ap3Aase-alpha and Ap3Aase-beta) were solubilized with 0.5% Triton X-100 from the particulate fraction. Ap3Aase-alpha resembled the cytosolic Ap3Aase (Ap3Aase-c), a known situation in liver. Comparative to Ap3Aase-alpha, Ap3Aase-beta showed a slightly higher Km (35 vs. 15 micron) and lower isoelectric point (5.25 vs. 5.45); Ap3Aase-beta was absent from the soluble fraction, and its recovery was unaffected by proteinase inhibitors, strongly arguing for distinct soluble and particulate turnover pathways for dinucleoside polyphosphates.
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PMID:Particulate diadenosine 5',5"'-P1,P3-triphosphate hydrolases in rat brain: two specific dinucleoside triphosphatases and two phosphodiesterase I-like hydrolases. 184 11

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.
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PMID:Fluoride is a strong and specific inhibitor of (asymmetrical) Ap4A hydrolases. 215 11

Dinucleosidetriphosphatase (EC 3.6.1.29) is present in both the 37,000 g rat liver supernatant and precipitate (50 mU/g each fraction). These two activities show matching molecular weights, isoelectric points, substrate specificities, Km values, bivalent cation requirements and inhibition by zinc (II). The particulate triphosphatase and a residual dinucleosidetetraphosphatase (EC 3.6.1.17) are solubilized by freeze-thawing or by Triton X-100. Detergent treatment also extracts an unspecific phosphodiesterase I activity (EC 3.1.4.1) which also splits dinucleoside polyphosphates. The above findings suggest the occurrence of cytosolic and particulate degradative pathways for dinucleoside polyphosphates.
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PMID:Occurrence of dinucleosidetriphosphatase in the cytosol and particulate fractions from rat liver. 299 62

Rat brain P1,P3-bis(5'-adenosyl)-triphosphate adenylohydrolase (dinucleosidetriphosphatase, EC 3.6.1.29) was purified 1000-fold. The enzyme hydrolyzed diadenosine and diguanosine triphosphates (Km values 14 and 40 microM, and relative V 100 and 40, respectively) to the corresponding nucleoside di and monophosphates. Dixanthosine triphosphate was hydrolyzed at a residual rate. Diadenosine di and tetraphosphates, NAD+, and artificial phosphodiesterase substrates were not hydrolyzed. Bivalent cations [Mg(II), Mn(II) or Ca(II)] were required for activity, but Zn(II) was a competitive inhibitor (Ki = 5 microM). The optimum pH value was about 7.5. A molecular mass of 34 kdalton (gel filtration) and an isoelectric point of 5.5 (chromatofocusing) were found.
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PMID:Dinucleosidetriphosphatase from rat brain. 608 16