title: Induction of penicillinase with inorganic phosphate.
abstract: Phosphate stimulates penicillinase formation in Bacillus cereus 569. The rate of penicillinase synthesis in the presence of 0.3 m phosphate, pH 7.0, is approximately 10-fold greater than that for uninduced cells, while the rate of synthesis in the presence of 0.3 m phosphate and 1 unit/ml of penicillin is approximately fourfold greater than in the presence of penicillin alone. When phosphate-induced cells are transferred to low phosphate medium, the rate of penicillinase synthesis rapidly reverts to that of uninduced cells. Furthermore, the phosphate-induced synthesis of the enzyme is inhibited by either chloramphenicol or actinomycin D. These antibiotics are known to inhibit protein synthesis and deoxyribonucleic acid-dependent ribonucleic acid (RNA) synthesis, respectively. Thus, phosphate appears to induce the synthesis of a species of RNA that is required for the synthesis of penicillinase in B. cereus 569. The penicillin-dependent induction lag for penicillinase was compared in high and low phosphate media. It was found that, at 37 C, the penicillin-dependent lag is approximately 3 min in the presence of 0.3 m phosphate and approximately 6 min in low phosphate medium.
mesh_terms: D001409:Bacillus cereus / Q000201:enzymology* / Q000254:growth & development; D001414:Bacitracin / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D003523:Cycloserine / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D004790:Enzyme Induction / Q000187:drug effects*; D010405:Penicillinase / Q000096:biosynthesis*; D010406:Penicillins / Q000378:metabolism / Q000494:pharmacology; D010710:Phosphates / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis; D013696:Temperature
chemical_list: D010406:Penicillins; D010710:Phosphates; D012333:RNA, Messenger; D001414:Bacitracin; D003609:Dactinomycin; D002701:Chloramphenicol; D003523:Cycloserine; D010405:Penicillinase