Beschreibung:
<jats:p>The aim of this study was to investigate the antimicrobial potential of 52
natural isolates of Lactobacillus casei/paracasei. The incidence of relevant
genes encoding BacSJ (bacSJ2-8/bacSJ2-8i gene cluster), acidocin 8912 (acdT),
ABC-transporter (abcT) and accessory protein (acc) was also studied. These
genes were found to be widespread amongst the analyzed L. casei/paracasei
strains. The bacSJ2-8/bacSJ2-8i gene cluster was present in 49 (94.23%) and
acdT in 41 (78.85%) of the 52 tested strains. Forty of these strains (76.92%)
harbored both analyzed genes. Interestingly, only 17 strains (32.69%) with
the bacSJ2-8/bacSJ2-8i gene cluster and/or the acdT gene showed bacteriocin
production. Strain L. paracasei BGNK1-62 contained the bacSJ2-8/bacSJ2-8i
gene cluster, but did not produce bacteriocin BacSJ possibly due to absence
of the abcT and acc genes. Hence, these genes were introduced into BGNK1-62
by transformation with constructed plasmid pA2A, after which BacSJ was
produced. In addition, it was found that L. paracasei BGGR2-66 produced new
bacteriocin designated as BacGR that was biochemically characterized and its
N- terminal sequence was determined.</jats:p>