OBJECTIVES The aim of this study was to investigate the molecular basis of an observed increasing resistance to trimethoprim and sulphonamides despite a simultaneous decline in co-trimoxazole consumption. The distribution of sulphonamide resistance genes sul1, sul2 and the recently discovered sul3 was studied in a collection of clinical isolates of Enterobacteriaceae. METHODS PCR with primers...

The combination of pyrimethamine and suiphonamide is effective prophylaxis against Plasmo&dm falciparum malaria (Lucas et al., 1969) and is specifically recommended for use in areas where chloroquine-resistant malaria is encountered such as Kenya (British National Formulary, 1983). The sulphonamide component of Fansidar is sulfadoxine, and we believe it is this sulphonamide which precipitated t...

The binding of substrates and inhibitors to dihydrofolate reductase was studied by steady-state kinetics and high-field 1H-n.m.r. spectroscopy. A series of 5-substituted 2,4-diaminopyrimidines were examined and were found to be 'tightly binding' inhibitors of the enzyme (Ki less than 10(-9) M). Studies on the binding of 4-substituted benzenesulphonamides and benzenesulphonic acids also establis...

The Fate of the Saccharin Impurities Toluene-2-Sulphonamide and 2,3-Dihydrobenz( d]isothiazole 1,l-Dioxide in the Rat ANDREW G. R E W I C K * and LOUISE M. BALL? *Faculty of Medicine, University of Southampton, Southampton SO9 3 TU, U.K., and ?Pharmacology Branch, N.I.E.H.S., Research Triangle Park, NC 27709, U.S.A. The non-nutritive sweetener, saccharin (2,3-dihydro-3-oxobenz[d]isothiazole 1,l...

Selection by sulphonamides was investigated in Neisseria gonorrhoeae because a sulphonamide-resistant (Sulr), methionine-requiring (Met-) phenotype that was common in the era of sulphonamide therapy became rare in the penicillin era. Cultures of wild-type (SulsMet+) gonococci on a conventional medium containing sulphadiazine (2-10 micrograms ml-1) yielded numerous, nonidentical mutations of two...

Abstract Sulphonamide drugs (sulphamethazine, sulphamerazine, sulphadiazine, sulphathiazole) were studied in a wide potential window (between 2 and − V) acetonitrile, dimethyl sulphoxide 50–50 v/v% binary mixtures of acetonitrile water. The voltammograms the outlined compounds very similar both anodic cathodic part each non-aqueous solvents except for sulphathiazole. These sulphonamide also inv...