title: Alteration of repression in purine biosynthesis.
mesh_terms: D000225:Adenine / Q000378:metabolism; D003470:Culture Media; D004794:Enzyme Repression; D006147:Guanine / Q000378:metabolism; D007042:Hypoxanthines / Q000378:metabolism; D008967:Molecular Biology; D009154:Mutation; D010088:Oxidoreductases / Q000096:biosynthesis*; D011687:Purines / Q000096:biosynthesis*; D012486:Salmonella typhimurium / Q000201:enzymology* / Q000378:metabolism*; D014970:Xanthines / Q000378:metabolism
chemical_list: D003470:Culture Media; D007042:Hypoxanthines; D011687:Purines; D014970:Xanthines; D006147:Guanine; D010088:Oxidoreductases; D000225:Adenine