Description of durancin TW-49M, a novel enterocin B-homologous bacteriocin in carrot-isolatedEnterococcus duransQU 49

Abstract

Aims: To characterize the novel bacteriocin produced by Enterococcus durans. Methods and Results: Enterococcus durans QU 49 was isolated from carrot and expressed bactericidal activity over 20–43°C. Bacteriocins were purified to homogeneity using the three‐step purification method, one of which, termed durancin TW‐49M, was an enterocin B‐homologous peptide with most identical residues occurring in the N‐terminus. Durancin TW‐49M was more tolerant in acidic than in alkali. DNA sequencing analysis revealed durancin TW‐49M was translated as a prepeptide of the double‐glycine type. Durancin TW‐49M and enterocin B expressed similar antimicrobial spectra, in which no significant variation due to the diversity in their C‐termini was observed. Conclusions: Durancin TW‐49M, a novel nonpediocin‐like class II bacteriocin, was characterized to the amino acid and genetic levels. The diverse C‐terminal parts of durancin TW‐49M and enterocin B were hardly to be suggested as the place determining the target cell specificity. Significance and Impact of the Study: This is the first and comprehensive study of a novel bacteriocin produced by Ent. durans. The high homology at the N‐terminal halves between durancin TW‐49M and enterocin B makes them suitable to study the structure‐function relationship of bacteriocins and their immunity proteins.

Enterocin F4-9, a Novel O -Linked Glycosylated Bacteriocin

“…The mode of action of enterocin F4-9 was analyzed by the method described previously according to the killing manner toward the indicator strain (14,23). Briefly, a culture of E. faecalis JCM 5803…”

Anti-listeria activity of Pediococcus pentosaceus BCC 3772 and application as starter culture for Nham, a traditional fermented pork sausage

“…Effects of pH and heat treatments on anti-listeria activity of the polypeptide from P. pentosaceus BCC 3772 were conducted as previously described (Worobo et al, 1994 andHu et al, 2008). Antilisteria activity was monitored following exposure to different pH values at 4 C for 24 in 0.4 mM universal buffers, pH 2e12 (Britton & Robinson, 1931).…”

“…Amplicon was purified and sequenced as described above (except that the DNA sequencing was performed by (Marcrogen, Korea). GENETYX-WIN (GENETYX-v.8.0, Japan) software was used as a tool to analyze the nucleotide sequences (Hu, Zendo, Nakayama, & Sonomoto, 2008) and homologue analysis was performed using BLAST.…”

Antilisterial activity of carrots: Effect of temperature and properties of different carrot fractions

“…Most authors have attributed the antilisterial activity to intrinsic factors of carrot tissue (Babic, Nguyen-the, Amiot & Aubert, 1994;Beuchat & Brackett, 1990;Nguyen-the & Lund, 1991;Nguyen-the & Lund, 1992), although the indigenous microflora of carrots has also been reported to exhibit an antagonistic activity against L. monocytogenes (Hu, Zendo, Nakayama & Sonomoto, 2008;Liao, 2007). Additionally, the antilisterial activity has been reported heat-labile, active over the pH range 5.8 to 7.0, oxygen-dependent, membrane-bound to carrot cells, with a proteinaceous character, and susceptible to mechanical stress during blending (Beuchat & Brackett, 1990;Nguyen-the & Lund, 1991;Nguyen-the & Lund, 1992;Magel, Wolf & Hammes, 2004).…”