Leuconostoc is a genus of gram-positive bacteria, placed within the family of Lactobacillaceae. They are generally ovoid cocci often forming chains. Leuconostoc spp. are intrinsically resistant to vancomycin and are catalase-negative (which distinguishes them from staphylococci). All species within this genus are heterofermentative and are able to produce dextran from sucrose. They are generally slime-forming. Blamed for causing the 'stink' when creating a sourdough starter, some species are also capable of causing human infection. Because they are an uncommon cause of disease in humans, standard commercial identification kits are often unable to identify the organism. Leuconostoc spp., along with other lactic acid bacteria such as Pediococcus and Lactobacillus, are responsible for the fermentation of cabbage, making it sauerkraut. In this process, fresh cabbage is fermented in a light brine, where the sugars in the cabbage are transformed by lactofermentation to lactic acid which gives the cabbage a sour flavour and good keeping qualities. Leuconostoc spp. are similarly part of the symbiotic colonies of bacteria and yeast (SCOBY) involved in the fermentation of kefir, a fermented milk beverage and kombucha, a fermented tea. The genus Leuconostoc comprises the following species: Leuconostoc carnosum Shaw and Harding 1989 Leuconostoc citreum Farrow et al. 1989 Leuconostoc falkenbergense Wu and Gu 2021 Leuconostoc fallax Martinez-Murcia and Collins 1992 "Leuconostoc garlicum" Kim et al. 2002 Leuconostoc gelidum Shaw and Harding 1989 Leuconostoc holzapfelii De Bruyne et al. 2007 Leuconostoc inhae Kim et al. 2003 Leuconostoc kimchii Kim et al. 2000 Leuconostoc lactis Garvie 1960 (Approved Lists 1980) Leuconostoc litchii Chen et al. 2020 Leuconostoc mesenteroides (Tsenkovskii 1878) van Tieghem 1878 (Approved Lists 1980) Leuconostoc miyukkimchii Lee et al. 2012 Leuconostoc palmae Ehrmann et al. 2009 Leuconostoc pseudomesenteroides Farrow et al. 1989 Leuconostoc rapi Lyhs et al. 2015 Leuconostoc suionicum (Gu et al.