The removal of intervening sequences (introns) from a primary RNA transcript is catalyzed by the spliceosome, a large ribonucleoprotein complex. At the start of each splicing cycle, the spliceosome assembles anew in a sequentially ordered manner on the pre-mRNA intron to be removed. We describe here the identification of a series of naphthalen-2-yl hydroxamate compounds that inhibit pre-mRNA sp...

[adenine-U-14C]ADP-ribose-agmatine and [adenineU-’4C]ADP-ribose-histone were synthesized by an NAD:arginine ADP-ribosyltransferase from [’*C]NAD and agmatine and histone, respectively. The pseudofirst order rate constants for breakdown of the two components either in 0.4 N NaOH or in 0.4 M neutral hydroxylamine were identical. Hydroxylamine treatment of [‘4C]ADP-ribose-agmatine or [32P]ADP-ribo...

New tripodal gem-(bis-phosphonates) uranophiles were discovered by a screening method that allowed for the selection of ligands with strong uranyl-binding properties in a convenient microtiter-plate format. The method is based on competitive uranium binding by using Sulfochlorophenol S as chromogenic chelate. This dye compound was found to present high uranyl complexation properties and allowed...

Acid dissociation constant (pKa) of some para-substituted benzohydroxamic, 4-XC6H4CONHOH, and N-methyl parasubstituted benzohydroxamic acids, 4XC6H4CON(OH)CH3, where X = H, CH3, CH3O, NO2, Cl, have been determined spectrophotometrically by nucleophilic substitution reactions of pnitrophenyl acetate with hydroxamate ions at 27± 0.1C. All reactions in this study follow pseudo-first order kinetics...

Previous studies have shown that there is a major difference between the iron release mechanism of enterobactin, a catechol-based siderophore, and that of the hydroxamate-based siderophores such as ferrichrome. For ferric enterobactin there is an esterase that hydrolyzes the ligand during iron release. In contrast, iron is released by the hydroxamate-based siderophores and the ligands are reuse...

A novel dry synthesis for the uranium(VI) dioxodiacetohydroxamate (UAHA) complex has been developed. The complex was generated in > 80% yield by mechanically grinding solid uranyl acetate dihydrate (UAc) with solid acetohydroxamic acid in stoichiometric amounts. The resulting UO2(AHA)2 ·4H2O solid is purified by washing with acetone. The stoichiometry was confirmed via colorimetric assays for U...

The cellular models generally used in the in vitro evaluation of anti-human immunodeficiency virus compounds are dividing cells. A model constituted by resting lymphocytes may more accurately reflect a drug's future efficacy in humans, since viral DNA synthesis is known to take place in quiescent cells, creating a reservoir of infected cells awaiting activation to complete their viral replicati...

Abstract A pilot study investigating the possible role of desferrioxamine B (DFOB) to prevent U VI precipitation in alkaline NaCl solutions was carried out. Desferrioxamine is a hydroxamate siderophore occurring naturally environment. The can possibly mobilize from wide range sources such as mine tailings, contaminated land and radioactive waste storage disposal facilities. results series batch...