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A coccal-shaped organism, designated 516T, was isolated from yan-tsai-shin (fermented broccoli stems), a traditional fermented food in Taiwan. 16S rRNA gene sequencing results showed that strain 516T had 98.9 % sequence similarity to that of the type strain Lactococcus garvieae NBRC 100934T. Comparison of three housekeeping genes, rpoA, rpoB and pheS, revealed that strain 516T was well separated from Lactococcus garvieae NBRC 100934T. DNA–DNA hybridization studies indicated that strain 516T had low DNA relatedness with Lactococcus garvieae NBRC 100934T (46.1 %). The DNA G+C content of strain 516T was 38.1 mol% and the major fatty acids were C16 : 0 (22.7 %), C19 : 0 cyclo ω8c (17.9 %) and summed feature 7 (29.0 %). Based on the evidence, strain 516T represents a novel species of the genus Lactococcus , for which the name Lactococcus formosensis sp. nov. is proposed. The type strain is 516T ( = NBRC 109475T = BCRC 80576T).

A coccal strain isolated from fresh broccoli was initially identified asEnterococcus saccharolyticus; however, molecular identification and phenotypic traits did not support this identification. DNA–DNA hybridization with the type strain ofE. saccharolyticus(76.4 % relatedness), DNA G+C content (35.7 mol%), phylogenetic analysis based on 16S rRNA,pheSandrpoAgene sequences, rep-PCR fingerprinting and profiles of cellular fatty acids, whole-cell proteins and enzyme activities, together with carbohydrate metabolism characteristics, indicated that this strain is distinct and represents a novel subspecies, for which the nameEnterococcus saccharolyticussubsp.taiwanensissubsp. nov. is proposed. The type strain is 812T( = NBRC 109476T = BCRC 80575T). Furthermore, we present an emended description ofEnterococcus saccharolyticusand proposal ofEnterococcus saccharolyticussubsp.saccharolyticussubsp. nov. (type strain ATCC 43076T = CCUG 27643T = CCUG 33311T = CIP 103246T = DSM 20726T = JCM 8734T = LMG 11427T = NBRC 100493T = NCIMB 702594T).

Enterococcus sp. 812, isolated from fresh broccoli, was previously found to produce a bacteriocin active against a number of Gram-positive bacteria, including Listeria monocytogenes. Bacteriocin activity decreased slightly after autoclaving (121 °C for 15 min), but was inactivated by protease K. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 4,521.34 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2-ATYYGNGVYXDKKKXWVEWGQA, by Edman degradation, which contained the consensus class IIa bacteriocin motif YGNGV in the N-terminal region. The obtained partial sequence showed high homology with some enterococcal bacteriocins; however, no identical peptide or protein was found. This peptide was therefore considered to be a novel bacteriocin produced by Enterococcus sp. 812 and was termed enterocin T.