title: Effect of cefaperazone/sulbactam and ampicillin/sulbactam on the in vitro activity of human erythrocyte glucose-6-phosphate dehydrogenase.
abstract: We investigated the effects of the antibiotic drugs cefaperazone/sulbactam and ampicillin/sulbactam on the in vitro activity of the enzyme glucose-6-phosphate dehydrogenase (G6PD). The enzyme was purified from human erythocytes using 2',5' ADP-Sepharose 4B affinity gel. The enzymatic activity was measured spectrophotometrically at 340 nm, according to the method of Beutler. The I50 values were determined from Activity % - [Drug] graphs, and the Ki constants and inhibition types for each drug were determined using Lineweaver-Burk graphs. The I50 value was 13.5 mg/ml for cefaperazone/sulbactam and 36 mg/ml for ampicillin/sulbactam. The Ki constants were 10.16 for ampicillin/sulbactam and 38.22 for cefaperazone/sulbactam. Cefaperazone/sulbactam competitively inhibited G6PD activity, whereas ampicillin/sulbactam non-competitively inhibited the activity of the enzyme.
authors.affiliation: Biotechnology and Research Center, Atatürk University, Erzurum, Turkey.
authors.forename: M
authors.initials: M
authors.lastname: Ciftçi
authors.forename: M E
authors.initials: ME
authors.lastname: Büyükokuroğlu
authors.forename: O I
authors.initials: OI
authors.lastname: Küfrevioğlu
mesh_terms: D000645:Ammonium Sulfate; D000667:Ampicillin / Q000494:pharmacology*; D001798:Blood Proteins / Q000737:chemistry; D002438:Cefoperazone / Q000008:administration & dosage*; D002846:Chromatography, Affinity; D004359:Drug Therapy, Combination / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D004912:Erythrocytes / Q000187:drug effects / Q000201:enzymology*; D005954:Glucosephosphate Dehydrogenase / Q000037:antagonists & inhibitors / Q000097:blood* / Q000187:drug effects; D006461:Hemolysis; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D013407:Sulbactam / Q000008:administration & dosage* / Q000494:pharmacology*
chemical_list: D001798:Blood Proteins; C035444:sultamicillin; D000667:Ampicillin; D002438:Cefoperazone; D005954:Glucosephosphate Dehydrogenase; D013407:Sulbactam; D000645:Ammonium Sulfate