title: Oxidation of thymidylate synthase by inorganic compounds.
abstract: Thymidylate synthase from methotrexate-resistant Lactobacillus casei was rapidly and completely inactivated by low concentrations of permanganate, periodate, or potassium triiodide at 0 degree C. The enzyme was not inactivated to any appreciable extent by iodate, iodide, ferricyanate, iodosobenzoate, or hydrogen peroxide. The inactivation by permanganate was retarded by the substrate 2'-deoxyuridylate and, to a lesser extent, by phosphate. Titration of enzyme activity with permanganate showed that two moles of permanganate were required to completely inactivate one mole of thymidylate synthase.
mesh_terms: D007202:Indicators and Reagents; D007454:Iodides; D007780:Lacticaseibacillus casei / Q000201:enzymology; D008780:Methyltransferases / Q000378:metabolism*; D010084:Oxidation-Reduction; D010504:Periodic Acid; D011196:Potassium Permanganate; D013940:Thymidylate Synthase / Q000378:metabolism*
chemical_list: D007202:Indicators and Reagents; D007454:Iodides; D011196:Potassium Permanganate; D010504:Periodic Acid; C009288:metaperiodate; D008780:Methyltransferases; D013940:Thymidylate Synthase; C010389:Lugol's solution