FIG. 2.

Schematic representation of PCR-derived inserts in pAMT1. Plasmid designations are indicated on the left. Maximum bacteriocin production conferred by the plasmids introduced into P. freudenreichii IFO12426 is indicated on the right. (A) Propionicin T1 inserts cloned as XbaI-SpeI fragments in the XbaI site of pAMT1. Propionicin T1 activity was measured using P. acidipropionicii 4965 as an indicator. (B) PAMP and pro-PAMP expression constructs cloned as XbaI-BamHI fragments in pAMT1. PAMP activity was measured using L. sakeii NCDO 2714 as an indicator. a, the pamA gene in the pTD110 plasmid contains a frameshift mutation that results in the expression of a 174-amino-acid pro-PAMP protein without the C-terminal PAMP domain; b, PAMP activity was only obtained after proteinase K treatment.