Aim To identify and characterize novel bacteriocins from Weissella hellenica 4-7. Methods and Results Weissella hellenica 4-7, isolated from the traditional Taiwanese fermented food sian-sianzih (fermented clams), was previously found to produce a bacteriocin active against Listeria monocytogenes and some other Gram-positive bacteria. Bacteriocin activity decreased slightly after autoclaving (121 degrees C for 15min), but was inactivated by protease K and trypsin. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 3205 center dot 6Da. N-terminal amino acid sequencing yielded a partial sequence, NH2-KGFLSWASKATSWLVGP, by Edman degradation. The obtained partial sequence showed high homology with leucocin B-TA33a; however, at least two different residues were observed. No identical peptide or protein was found, and this peptide was therefore considered to be a novel bacteriocin produced by W.hellenica 4-7 and termed weissellicin L. Conclusions The findings obtained in the current study suggest a novel bacteriocin produced by W.hellenica 4-7. Significance and Impact of the Study Bacteriocins from Weissella remain rare, and this study is the second report of a bacteriocin produced by W.hellenica.