title: The number of catalytically essential carboxyl groups in pepsin. Modification of the enzyme by trimethyloxonium fluoroborate.
mesh_terms: D001665:Binding Sites / Q000187:drug effects; D001881:Borates / Q000138:chemical synthesis; D002247:Carbon Isotopes; D002264:Carboxylic Acids; D055598:Chemical Phenomena; D002621:Chemistry; D005461:Fluorine; D008722:Methods; D008745:Methylation; D009861:Onium Compounds / Q000138:chemical synthesis; D010434:Pepsin A / Q000032:analysis* / Q000378:metabolism; D011487:Protein Conformation / Q000187:drug effects
chemical_list: D001881:Borates; D002247:Carbon Isotopes; D002264:Carboxylic Acids; D009861:Onium Compounds; D005461:Fluorine; D010434:Pepsin A