Expression of five class II bacteriocins with activity against in CNCM I-5369, and in a heterologous host.

Five open reading frames viz , and coding class II bacteriocins in CNCM I-5369 strain previously isolated from an Algerian dairy product, were found to be expressed after 24 h of growth. The strain has also shown anti- activity in a narrow pH range between 4.5 and 5. Then, expression and purification of these bacteriocins was conducted in the heterologous host . This strategy enabled us to purify the peptide encoded by in large quantities, in contrast to other peptides that were produced but required to be released from the insoluble fraction following 4 M urea and desalting treatments. All peptides heterologously produced were characterized by MALDI TOF Mass spectrometry and successfully tested for their anti- activity. Furthermore, transcriptional analysis was determined by Findterm tool and with Bagel4 software permitted to locate potential promoters and co-transcription events.