Amin oxidase

Four substrate analogs, 4-(2-naphthyloxy)-2-butyn-1-amine (1), 1,4-diamino-2-chloro-2-butene (2), 1,6-diamino-2,4hexadiyne (3), and 2-chloro-5-phthalimidopentylamine (4) have been tested as inhibitors against mammalian, plant, bacterial, and fungal copper-containing amine oxidases: bovine plasma amine oxidase (BPAO), equine plasma amine oxidase (EPAO), pea seedling amine oxidase (PSAO), Arthrobacter globiformis amine oxidase (AGAO), Escherichia coli amine oxidase (ECAO), and Pichia pastoris lysyl oxidase (PPLO).

14p research12 01-06-2013 43 6   Download

The product of agmatine oxidation catalyzed by Pisum sativum L. copper amine oxidase has been identified by means of one- and two-dimensional 1H-NMR spectroscopy to be N-amidino-2-hydroxypyrrolidine. This compound inhibits competitively rat nitric oxide synthase type I and type II (NOS-I and NOS-II, respectively) and bovine trypsin (trypsin) activity, values of Ki being (1.1 ± 0.1) · 10)5 M (at pH 7.5 and 37.0 °C), (2.1 ± 0.1) · 10)5 M (at pH 7.5 and 37.0 °C), and (8.9 ± 0.4) · 10)5 M (at pH 6.8 and 21.0 °C), respectively. ...

9p research12 01-06-2013 31 2   Download

1,5-Diamino-2-pentyne (DAPY) was found to be a weak substrateof grasspea (Lathyrus sativus,GPAO) andsainfoin (Onobrychis viciifolia, OVAO) amine oxidases. Prolonged incubations, however, resulted in irreversible inhibition of both enzymes. For GPAOandOVAO, rates of inactivation of 0.1–0.3 min )1 were determined, the apparentKI values (half-maximal inactivation) were of the order of 10 )5 M. DAPY was found to be amechanism-based inhibitor of the enzymes because the substrate cadaverine significantly pre-vented irreversible inhibition. ...

0p awards 05-04-2013 38 3   Download

For bovine serum amine oxidase, two different mechanisms of substrate-induced inactivation have been proposed. One consists of a slow oxidation by H2O2of a conserved residue in the reduced enzyme after the fast turnover phase [Pietr-angeli, P., Nocera, S., Fattibene, P., Wang, X.T., Mondovı`, B. &Morpurgo, L. (2000)Biochem. Biophys. Res. Commun. 267, 174–178] and the other of the oxidation byH2O2of the dihydrobenzoxazole in equilibrium with the product Schiff base, during the catalytic cycle [Lee, Y., Shepard, E., Smith, J., Dooley, D.M. & Sayre, L.M. (2001)Biochemistry40, 822–829]. ...

7p dell39 03-04-2013 47 3   Download

The interaction of xenon with copper⁄6-hydroxydopa (2,4,5-trihydroxy-phenethylamine) quinone (TPQ) amine oxidases from the plant pulses lentil (Lens esculenta) and pea (Pisum sativum) (seedlings), the perennial Mediter-ranean shrub Euphorbia characias(latex), and the mammals cattle (serum) and pigs (kidney), were investigated by NMR and optical spectroscopy of the aqueous solutions of the enzymes.

11p galaxyss3 21-03-2013 43 5   Download

The two forms of monoamine oxidase, monoamine oxidase A and mono-amine oxidase B, have been associated with imidazoline-binding sites (type 2). Imidazoline ligands saturate the imidazoline-binding sites at nanomolar concentrations, but inhibit monoamine oxidase activity only at micromolar concentrations, suggesting two different binding sites [Ozaita A, Olmos G, Boronat MA, Lizcano JM, Unzeta M & Garcı´a-Sevilla JA (1997) Br J Pharmacol121,901–912].

9p galaxyss3 21-03-2013 28 4   Download

Two ORFs encoding a protein related to bacterial dimethylglycine oxidase were cloned from Pyrococcus furiosus DSM 3638. The protein was expressed in Escherichia coli, purified, and shown to be a flavoprotein amine dehydrogenase. The enzyme oxidizes the secondary aminesl-proline, l-pipecolic acid and sarcosine, with optimal catalytic activity towards l-proline.

18p galaxyss3 19-03-2013 58 4   Download

A common feature of all the proposed mechanisms for monoamine oxidase is the initiation of catalysis with the deprotonated form of the amine sub-strate in the enzyme–substrate complex. However, recent steady-state kinetic studies on the pH dependence of monoamine oxidase led to the sug-gestion that it is the protonated form of the amine substrate that binds to the enzyme.

9p galaxyss3 07-03-2013 46 4   Download

The structures of copper amine oxidases from various sources show good similarity, suggesting similar catalytic mechanisms for all members of this enzyme family. However, the optimal substrates for each member differ, depending on the source of the enzyme and its location.

12p cosis54 05-01-2013 47 5   Download

Các thuốc chống trầm cảm có thể được chia thành 3 loại lớn, gồm có các thuốc chống trầm cảm 3 vòng (tricyclic antidepressants = TCAs ), monoamine oxidase inhibitors (MAOIs) và các thuốc mới hơn được gọi là các thuốc chống trầm cảm không điển hình (atypicals), dị vòng (heterocyclic) hoặc thế hệ thứ hai (second-generation). Các thuốc chống trầm cảm 3 vòng (TCAs) được xếp loại thành amines đệ nhị hoac đệ tam và chứa một chuỗi bên với một số thay đổi nhóm methyl. ...

14p thiuyen111 11-04-2011 142 10   Download

Compared with hydrophilic drugs not undergoing transport, lipophilic drugs are more rapidly taken up from the blood into hepatocytes and more readily gain access to mixed-function oxidases embedded in sER membranes. For instance, a drug having lipophilicity by virtue of an aromatic substituent (phenyl ring) (B) can be hydroxylated and, thus, become more hydrophilic (Phase I reaction, p. 34). Besides oxidases, sER also contains reductases and glucuronyl transferases. The latter conjugate glucuronic acid with hydroxyl, carboxyl, amine, and amide groups (p.

12p bigbaby87 04-09-2010 115 10   Download