''Leuconostoc'' is a genus of

gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bac ...

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...

, placed within the family of

Lactobacillaceae The ''Lactobacillaceae'' are a family of lactic acid bacteria. It is the only family in the lactic acid bacteria which includes homofermentative and heterofermentative organisms; in the ''Lactobacillaceae,'' the pathway used for hexose fermentati ...

. They are generally ovoid

cocci A coccus (plural cocci) is any bacterium or archaeon that has a spherical, ovoid, or generally round shape. Bacteria are categorized based on their shapes into three classes: cocci (spherical-shaped), bacillus (rod-shaped) and spiral ( of wh ...

often forming chains. ''Leuconostoc'' spp. are intrinsically resistant to

vancomycin Vancomycin is a glycopeptide antibiotic medication used to treat a number of bacterial infections. It is recommended intravenously as a treatment for complicated skin infections, bloodstream infections, endocarditis, bone and joint infection ...

and are

catalase Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting t ...

-negative (which distinguishes them from

staphylococci ''Staphylococcus'' is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillales. Under the microscope, they appear spherical ( cocci), and form in grape-like clusters. ''Staphylococcus'' species are facultativ ...

). All species within this genus are

heterofermentative Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen. In fo ...

and are able to produce

dextran Dextran is a complex branched glucan (polysaccharide derived from the condensation of glucose), originally derived from wine. IUPAC defines dextrans as "Branched poly-α-d-glucosides of microbial origin having glycosidic bonds predominantly C-1 � ...

from

sucrose Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refi ...

. They are generally slime-forming. Blamed for causing the 'stink' when creating a

sourdough starter Sourdough or sourdough bread is a bread made by the fermentation of dough using wild lactobacillaceae and yeast. Lactic acid from fermentation imparts a sour taste and improves keeping qualities. History In the ''Encyclopedia of Food Microb ...

, 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 ''Pediococcus'' is a genus of gram-positive lactic acid bacteria, placed within the family of Lactobacillaceae. They usually occur in pairs or tetrads, and divide along two planes of symmetry, as do the other lactic acid cocci genera ''Aerococcu ...

'' and ''

Lactobacillus ''Lactobacillus'' is a genus of Gram-positive, aerotolerant anaerobes or microaerophilic, rod-shaped, non-spore-forming bacteria. Until 2020, the genus ''Lactobacillus'' comprised over 260 phylogenetically, ecologically, and metabolically di ...

'', are responsible for the fermentation of cabbage, making it

sauerkraut Sauerkraut (; , "sour cabbage") is finely cut raw cabbage that has been fermented by various lactic acid bacteria. It has a long shelf life and a distinctive sour flavor, both of which result from the lactic acid formed when the bacteria fe ...

. In this process, fresh cabbage is fermented in a light

brine Brine is a high-concentration Solution (chemistry), solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of ...

, where the sugars in the cabbage are transformed by lactofermentation to

lactic acid Lactic acid is an organic acid. It has a molecular formula . It is white in the solid state and it is miscible with water. When in the dissolved state, it forms a colorless solution. Production includes both artificial synthesis as well as natur ...

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 Symbiotic culture of bacteria and yeast (SCOBY) is a culinary symbiotic fermentation culture ( starter) consisting of lactic acid bacteria (LAB), acetic acid bacteria (AAB), and yeast which arises in the preparation of sour foods and beverag ...

) involved in the fermentation of

kefir Kefir ( ; also spelled as kephir or kefier; ; ; ) is a fermented milk drink similar to a thin yogurt or ayran that is made from kefir grains, a specific type of mesophilic symbiotic culture. The drink originated in the North Caucasus, in pa ...

, a fermented milk beverage and

kombucha Kombucha (also tea mushroom, tea fungus, or Manchurian mushroom when referring to the culture; Latin name ''Medusomyces gisevii'') is a fermented, lightly effervescent, sweetened black tea drink commonly consumed for its purported health b ...

, a fermented tea.

Species

The genus ''Leuconostoc'' comprises the following species: * ''

Leuconostoc carnosum ''Leuconostoc carnosum'' is a lactic acid bacterium; its type strain is NCFB 2776. Its genome has been sequenced. Its name derives from the fact that it was first isolated from chill-stored meats. Its significance is that it thrives in anaerobic ...

'' Shaw and Harding 1989 * ''

Leuconostoc citreum ''Leuconostoc citreum'' is a vancomycin- resistant, Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two bro ...

'' Farrow ''et al''. 1989 * ''

Leuconostoc falkenbergense ''Leuconostoc falkenbergense'' is a bacterium from the genus of ''Leuconostoc ''Leuconostoc'' is a genus of gram-positive bacteria, placed within the family of Lactobacillaceae. They are generally ovoid cocci often forming chains. ''Leuco ...

'' Wu and Gu 2021 * ''

Leuconostoc fallax ''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 ( ...

'' Martinez-Murcia and Collins 1992 * "''Leuconostoc garlicum''" Kim ''et al''. 2002 * ''

Leuconostoc gelidum Leuconostoc gelidum is a Gram-positive lactic acid bacterium; its type strain is NCFB 2775. Its genome has been sequenced.Kim, Dae-Soo, et al. "Genome Sequence of Leuconostoc gelidum KCTC 3527, Isolated from Kimchi." Journal of Bacteriology 193. ...

'' Shaw and Harding 1989 * ''

Leuconostoc holzapfelii ''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 ( ...

'' De Bruyne ''et al''. 2007 * ''

Leuconostoc inhae ''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 (wh ...

'' Kim ''et al''. 2003 * ''

Leuconostoc kimchii ''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 ( ...

'' Kim ''et al''. 2000 * ''

Leuconostoc lactis ''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 (wh ...

'' Garvie 1960 (Approved Lists 1980) * ''

Leuconostoc litchii ''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-negativ ...

'' Chen ''et al''. 2020 * ''

Leuconostoc mesenteroides ''Leuconostoc mesenteroides'' is a species of lactic acid bacteria associated with fermentation, under conditions of salinity and low temperatures (such as lactic acid production in fermented sausages). In some cases of vegetable and food storag ...

'' (Tsenkovskii 1878) van Tieghem 1878 (Approved Lists 1980) * ''

Leuconostoc miyukkimchii ''Leuconostoc miyukkimchii'' is a Gram-positive, non-spore-forming, facultatively anaerobic and non-motile bacterium from the genus of ''Leuconostoc'' which has been isolated from the fermented algae ''Undaria pinnatifida'' from Korea Ko ...

'' Lee ''et al''. 2012 * ''

Leuconostoc palmae ''Leuconostoc palmae'' is a Gram-positive, non-spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Sp ...

'' Ehrmann ''et al''. 2009 * ''

Leuconostoc pseudomesenteroides ''Leuconostoc pseudomesenteroides'' is an intrinsically vancomycin- resistant, Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly cla ...

'' Farrow ''et al''. 1989 * ''

Leuconostoc rapi ''Leuconostoc rapi'' is a Gram-positive bacterium from the genus of '' Leuconostoc'' which has been isolated from a rutabaga in Finland. References Lactobacillaceae Bacteria described in 2015 {{Firmicutes-stub ...

'' Lyhs ''et al''. 2015 * ''

Leuconostoc suionicum ''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-negativ ...

'' (Gu ''et al''. 2012) Jeon ''et al''. 2017

''Leuconostoc citrovorum''

The name ''Leuconostoc citrovorum'' (Hammer) Hucker and Pederson 1931 was rejected in 1971 as a ''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a s ...

'' by the Judicial Commission of

International Committee on Systematics of Prokaryotes The International Committee on Systematics of Prokaryotes (ICSP), formerly the International Committee on Systematic Bacteriology (ICSB), is the body that oversees the nomenclature of prokaryotes, determines the rules by which prokaryotes are named ...

(in Opinion 45).

Phylogeny

The currently accepted taxonomy is based on the

List of Prokaryotic names with Standing in Nomenclature List of Prokaryotic names with Standing in Nomenclature (LPSN) is an online database that maintains information on the naming and taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical ...

and the phylogeny is based on whole-genome sequences.

References

External links

List of species of the genus ''Leuconostoc''

''Leuconostoc''
MicrobeWiki Lactobacillaceae Garde manger Bacteria used in dairy products Bacteria genera {{lactobacilli-stub