Figure 3

Genetic replacement study of combinations of the lacticin 3147 structural genes for the staphylococcin C55 structural genes on pMRC01. Genetic organization of S. aureus C55 pETB plasmid (gene cluster of staphylococcin C55) is represented by black arrows and L. lactis DPC3147 pMRC01 (gene cluster of lacticin 3147) is represented by white arrows. A. MG1363 pMRC01 with ltnA1A2 genes exactly replaced with staphylococcin C55 structural genes, sacαAsacβA, this construct is called Mutant A. B. MG1363 pMRC01 with ltnA1 structural gene exactly replaced by sacαA structural gene, this construct is called ltn A1/Sacα Hybrid. It also contains the wild type ltn A2 gene. C. MG1363 pMRC01 with ltnA2 structural gene exactly replaced by sacβA structural gene, this construct is called ltn A2/Sacβ Hybrid. It also contains the wild type ltn A1 gene. The well diffusion assay on the left of the constructs shows activity of a purified preparation (through a Varian C18 column) of the construct alone and the well diffusion assays on the right hand side shows activity after complementation with purified lacticin 3147 or staphylococcin C55 peptides. Mass spectrometry analysis of the constructs indicates the mass of the peptides produced. The scale of the y-axis of the mass spec. is A) 2800–3600 mass/charge, B) 2300–3700 mass/charge and C) 2700–4000 mass/charge.