Although the first steps of the oxidation of methionine containing peptides by OH radicals have been very well documented, not much is known about the final products. They have been characterized and unraveled by mass spectrometry and IR Multiple Photon Dissociation (IRMPD) spectroscopy carried ...

It is known that reactive oxygen species can oxidize methionine residues in proteins in a non-stereospecific manner, and cells have mechanisms to reverse this damage. MsrA and MsrB are members of the methionine sulfoxide family of enzymes that specifically reduce the S and R forms, respectively,...

From chicken egg-white a broad specificity aminopeptidase is isolated. The presence of high molecular mass, hydrophobic aminopeptidase is also revealed. Isolated enzyme hydrolysed aliphatic, aromatic and basic aminoacyl-2-naphthylamides, and di- to hexapeptides, with a preference for methionine ...

The enkephalin analog, D-Ala2, ΔzPhe4 amide, has been prepared and shown to be five times as active as D-Ala2-methionine enkephalin amide invitro and the dehydrophenylalanine moiety conferred complete stability to chymotrypsin on the peptide.

Extract from the abdominal ganglia of Aplysia was fractionationed by high performance liquid chromatography. Several large uv absorbing peaks were found. One of these peaks from the ganglionic extract was analyzed by displacement assay with the use of Mytilus edulis membranes. The results reveal...

Drugs acting on androgen receptors modify opioid transmission in the central nervous system. To investigate a direct interaction, we studied whether the binding of [3H]diprenorphine to mouse brain membranes was modified by cyproterone acetate (progesterone derivative with antiandrogen activity),...

Recent reports have suggested that neurotensin (NT) and some of its analogues resemble neuroleptics, for example α-flupenthixol (FLU), in their ability to suppress locomotor activity. The results obtained support this conclusion, but only if total photocell counts (the “traditional” index) ar...

The peptidase-resistant derivative of neurotensin, [d-Trp11]neurotensin, has been continuously infused intracerebroventricularly (75 ng/h) with an osmotic minipump for 10 days. On several days during this infusion the locomotor activity, the body temperature, the food intake, the body weight, an...

Neurotensin injected intracerebroventricularly at the dose of 30 ng per rat was without intrinsic effect on locomotion. When associated with the enkephalinase inhibitor thiorphan (50 μg, intracerebroventricular) it decreased locomotor activity. On the contrary, the 3 μg dose of NT, which had a...

Rats received one daily i.p. injection of the dopamine uptake inhibitor GBR12783 (1-[2-(diphenylmethoxy)ethyl]4-(3-phenyl-2-(propenyl)-piperazine) (10 mg/kg) or vehicle for 9 days. Fourteen days after discontinuing treatment, their locomotor activity was assessed after injection of GBR12783 (5 m...

Intracerebroventricular (i.c.v.) administration of [D-Trp11]neurotensin to rats decreased locomotor activity at a low dose (30 ng) and increased it at a high dose (750 ng). Only this high dose increased the dopamine turnover in the nucleus accumbens. The locomotor stimulant effect elicited by th...

The stability of neurotensin (NT) and a potent, long lasting analogue, [d-Trp11]-NT, to rat brain peptidases was compared by incubating the peptides with subcellular fractions (synaptosomes, synaptic membranes) and a purified endopeptidase from rat brain. Degradation of the peptides with time wa...

The stereoselectivity of a recently isolated ω-transaminase from Chromobacterium violaceum in the amination of 1,3-dihydroxy-1-phenylpropan-2-one has been determined. The enzyme is not enantioselective towards a racemic mixture of 1,3-dihydroxy-1-phenylpropan-2-one but is highly stereoselective...

The acidity constants of the protonated buffers given in the title, i.e. of H(Tea)+, H(tris)+ and H(Bistris)+, have been measured at 25 °C in water, 50% aqueous dioxane or methanol, and in 75 or 90% dimethylsulfoxide (Dmso) with tetramethylammonium nitrate as background electrolyte. The interac...

The present work was aimed to separate, identify and characterize the major degradation products of tramadol hydrochloride and ketorolac tromethamine. A rapid, specific and accurate stability indicating reversed phase liquid chromatographic method has been developed for simultaneous determinatio...

2-Substituted 2-aminoethanol was shown to be the minimum essential structure for the immunosuppressive activity of ISP-i (myriocin, thermozymocidin) by simplification of 2-substituted 2-amino-1,3-propanediol, which was generated by modification of ISP-I. Among the series, 2-amino-4-(4-octylpheny...

Copper(II) and nickel(II) complexes of 2-amino-2-(hydroxymethyl)-1,3-propanediol have been studied in aqueous solution at 25° and at an ionic strength of 0·10 M. The equilibrium constants for the various species present in solution have been determined from potentiometric measurements of hydro...

A new strategy for racemization of the 2-amino-1,3-propanediol 2b, based on a chemoselective oxazoline ring formation and a highly diastereoselective reduction of the ketone 4 is reported.

This study reports novel CO2-selective crosslinked thin film composite poly(vinyl alcohol) (PVA)/amine blend membranes, its structural characterizations and permeation studies. The characteristic properties of the active layer were examined with Thermogravimetric analysis (TGA), Differential sca...

FTY720 (2-amino-2-[2-(4-octylphenyl)ethyl]-1,3-propanediol hydrochloride), a novel synthetic immunosuppressant led by modification of ISP-I (myriocin, thermozymocidin) displayed potent immunosuppressive activity both in vitro and in vivo.