Başbülbül, G., Ozteber, M., Halil Bıyık, H., Oryaşın, E., Bozdoğan, B

Antibacterial activities of thermophilic bacteria were reported in previous studies. Whole genome sequences of thermophilic bacteria indicated presence of bacteriocin genes. In this study, 43 thermophilic bacteria isolated from hot spring, thermal mud and soil samples with antibacterial activity were screened for presence of 15 bacteriocin genes. Identification of thermophilic isolates was done by 16S rRNA gene sequencing. PCR reactions for bacteriocin gene screening were carried out by using primers specific for Pediocin, Plantaricin, Enterocin A, Enterocin B, Enterocin P, Enterocin Q, Enterocin L50 A/B, Enterocin AS-48, bact31, Cytolysin, Nisin, Lacticin 481, Lactococcin A, Enterolysin A and Lysostaphin genes. Sequence analysis indicated that thermophilic isolates were from the Anoxybacillus (n=18), Geobacillus (n=17), Aeribacillus (n=8) genera. The entA and entB structural genes were detected in 38 and 12 of 43 isolates, respectively. All isolates with entB gene also carried entA gene. Only 5 isolates were negative for both entA and entB genes. The results of sequencing and BLAST analyses of amplified genes showed homology with entA (91-100%) and entB (93-100%) genes. Our results showed that entA and entB bacteriocin genes are widely disseminated among these newly isolated thermophilic bacteria.