''Latilactobacillus sakei'' is the type species of the genus ''Latilactobacillus'' that was previously classified in the genus ''

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 diver ...

''. It is homofermentative; hexoses are metabolized via

glycolysis Glycolysis is the metabolic pathway that converts glucose () into pyruvate (). The free energy released in this process is used to form the high-energy molecules adenosine triphosphate (ATP) and reduced nicotinamide adenine dinucleotide (NADH ...

to lactic acid as main metabolite; pentoses are fermented via the Phosphoketolase pathway to lactic and acetic acids.

Uses

Antilisterial ''Listeria'' is a genus of bacteria that acts as an intracellular parasite in mammals. Until 1992, 17 species were known, each containing two subspecies. By 2020, 21 species had been identified. The genus is named in honour of the British pio ...

strains of ''L. sakei'' are used in Europe for the production of

saucisson Saucisson () or saucisson sec is a family of thick, dry-cured sausages in French cuisine. Typically made of pork, or a mixture of pork and other meats, saucisson are a type of charcuterie similar to salami or summer sausage. Origin Saucisso ...

and can be used for the conservation of fresh meat. ''L. sakei'' strains isolated from traditional

dry sausage Fermented sausage, or dry sausage, is a type of sausage that is created by salting chopped or ground meat to remove moisture, while allowing beneficial bacteria to break down sugars into flavorful molecules. Bacteria, including ''Lactobacillus'' ...

have a potential use as starter cultures. Inhibition of ''

Listeria monocytogenes ''Listeria monocytogenes'' is the species of pathogenic bacteria that causes the infection listeriosis. It is a facultative anaerobic bacterium, capable of surviving in the presence or absence of oxygen. It can grow and reproduce inside the host' ...

'' in chicken cold cuts can be obtained by addition of sakacin P and sakacin P-producing ''Lactobacillus sakei''. Strain ''2a'' of the subspecies ''L. sakei subsp. sakei'' can also be isolated from meat products. Research suggests that ''L. sakei'' may play a role in maintaining healthy sinus cavities and preventing sinusitis.

Biochemistry

Bacteriocins production

Sakacins are

bacteriocin Bacteriocins are proteinaceous or peptidic toxins produced by bacteria to inhibit the growth of similar or closely related bacterial strain(s). They are similar to yeast and paramecium killing factors, and are structurally, functionally, and ec ...

s of class II produced by ''L. sakei''. In strain ''CCUG 42687'', their production is dependent on nutrients, temperature and pH. Using the same strain, sakacin P can be produced in a completely defined medium. In strain ''CTC 494'', the presence of salt and a curing agent (

sodium chloride Sodium chloride , commonly known as salt (although sea salt also contains other chemical salts), is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. With molar masses of 22.99 and 35.45 g ...

and

sodium nitrite Sodium nitrite is an inorganic compound with the chemical formula NaNO2. It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. From an industrial perspective, it is the most important nitrite ...

) reduces the production of the

antilisterial ''Listeria'' is a genus of bacteria that acts as an intracellular parasite in mammals. Until 1992, 17 species were known, each containing two subspecies. By 2020, 21 species had been identified. The genus is named in honour of the British pio ...

bacteriocin

sakacin K Sakacins are bacteriocins produced by ''Lactobacillus sakei''. They are often clustered with the other lactic acid bacteriocins. The best known sakacins are sakacin A, G, K, P, and Q. In particular, sakacin A and P have been well characterized. ...

. Growth of CTC 494 is also dependent on nutrients availability. Lactocin S is a bacteriocin produced by strain ''L45'' of ''Lactobacillus sakei''.

Exopolysaccharide biosynthesis

Strain ''0–1'' of ''L. sakei'' produces

exopolysaccharide Extracellular polymeric substances (EPSs) are natural polymers of high molecular weight secreted by microorganisms into their environment. EPSs establish the functional and structural integrity of biofilms, and are considered the fundamental comp ...

Prevention

Eugenol Eugenol is an allyl chain-substituted guaiacol, a member of the allylbenzene class of chemical compounds. It is a colorless to pale yellow, aromatic oily liquid extracted from certain essential oils especially from clove, nutmeg, cinnamon, basil ...

is a chemical compound that can be used to reduce the presence of ''L. sakei'' as it disrupts its

cellular membrane The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment (t ...

Genetics

Genetic diversity within ''L. sakei'' has been assessed through the use of specifically designed

PCR primer PCR or pcr may refer to: Science * Phosphocreatine, a phosphorylated creatine molecule * Principal component regression, a statistical technique Medicine * Polymerase chain reaction ** COVID-19 testing, often performed using the polymerase chain ...

s for detection using randomly amplified polymorphic DNA, or by multi-locus sequence typing.

Bacteriocin genes

Bacteriocin genes are located either on chromosomes or on plasmids. Strain ''5'' produces a plasmid-encoded bacteriocin that is identical to sakacin P, as well as two chromosomally encoded bacteriocins, which were designated

sakacin T Sakacins are bacteriocins produced by ''Lactobacillus sakei''. They are often clustered with the other lactic acid bacteriocins. The best known sakacins are sakacin A, G, K, P, and Q. In particular, sakacin A and P have been well characterized. ...

and

sakacin X Sakacins are bacteriocins produced by ''Lactobacillus sakei''. They are often clustered with the other lactic acid bacteriocins. The best known sakacins are sakacin A, G, K, P, and Q. In particular, sakacin A and P have been well characterized. ...

. LasX is a transcriptional regulator of the lactocin S biosynthetic genes in strain ''L45'' of ''Lactobacillus sakei''.

Other genes

In strain ''LTH677'', a starter organism used in meat fermentation, there is an oxygen-dependent regulation of the expression of the

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 ...

gene

katA ''Kata'' is a Japanese word ( 型 or 形) meaning "form". It refers to a detailed choreographed pattern of martial arts movements made to be practised alone. It can also be reviewed within groups and in unison when training. It is practised ...

. In strain ''LTH681'', the stress operon

dnaK The 70 kilodalton heat shock proteins (Hsp70s or DnaK) are a family of conserved ubiquitously expressed heat shock proteins. Proteins with similar structure exist in virtually all living organisms. Intracellularly localized Hsp70s are an importa ...

has been characterized in 1999 as a heat shock protein gene. There is only one gene ( IdhL) responsible for the lactic fermentation.

Plasmids

A Theta-type

plasmid A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently. They are most commonly found as small circular, double-stranded DNA molecules in bacteria; how ...

has been characterized in ''Lactobacillus sakei'' in 2003. It is a potential basis for Low-Copy-Number vectors in lactobacilli. Vectors for inducible gene expression in ''L. sakei'' can be constructed. The key elements of these vectors are a regulatable promoter involved in the production of the bacteriocins sakacin A and sakacin P and the genes encoding the cognate histidine protein kinase and

response regulator A response regulator is a protein that mediates a cell's response to changes in its environment as part of a two-component regulatory system. Response regulators are coupled to specific histidine kinases which serve as sensors of environmental cha ...

that are necessary to activate this promoter upon induction by a peptide pheromone.

Genome

The genome of the meat-borne lactic acid bacterium ''Lactobacillus sakei 23K'' has been published in 2005. It is composed of 1884661 nucleotides forming 1879 protein genes and 84 RNA genes.''Lactobacillus sakei'' genome on KEGG at www.genome.jp
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References

External links

''Lactobacillus sakei'' on microbewiki.kenyon.eduType strain of ''Lactobacillus sakei'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
{{Taxonbar, from=Q3825347 Lactobacillaceae Bacteria described in 1934