''Levilactobacillus brevis'' is a

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 bacte ...

, rod shaped species of

lactic acid bacteria Lactobacillales are an order of gram-positive, low-GC, acid-tolerant, generally nonsporulating, nonrespiring, either rod-shaped (bacilli) or spherical (cocci) bacteria that share common metabolic and physiological characteristics. These bacte ...

which is heterofermentative, creating CO₂, lactic acid and acetic acid or ethanol during fermentation. ''L. brevis'' is the type species of the genus ''Levilactobacillus'' (previously ''L. brevis'' group), which comprises 24 species
http://www.lactobacillus.ualberta.ca/
http://www.lactobacillus.uantwerpen.be/).16SrRNA gene sequences. Journal of Applied Microbiology, 92(3), 451-459.">Pavlova, S. I., Kilic, A. O., Kilic, S. S., So, J. S., Nader‐Macias, M. E., Simoes, J. A., & Tao, L. (2002). Genetic diversity of vaginal lactobacilli from women in different countries based on 16S rRNA gene sequences. Journal of Applied Microbiology, 92(3), 451-459. It can be found in many different environments, such as

fermented foods In food processing, fermentation is the conversion of carbohydrates to alcohol or organic acids using microorganisms—yeasts or bacteria—under anaerobic (oxygen-free) conditions. Fermentation usually implies that the action of microorganisms ...

, and as normal microbiota. ''L.brevis'' is found in food such as

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 ferm ...

and

pickles Pickles may refer to: Dogs * Pickles (dog) (died 1967), a dog that found the stolen World Cup trophy in 1966 * Pickles (pickleball), a dog often cited as the name origin for the sport of pickleball * Mr. Pickles, the titular demonic dog in ...

. It is also one of the most common causes of

beer Beer is one of the oldest and the most widely consumed type of alcoholic drink in the world, and the third most popular drink overall after water and tea. It is produced by the brewing and fermentation of starches, mainly derived from ce ...

spoilage. Ingestion has been shown to improve human immune function, and it has been

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...

ed several times. Normal gut microbiota ''L.brevis'' is found in human

intestines The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans ...

vagina In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...

, and feces. ''L. brevis'' is one of the major lactobacilli found in

tibicos Tibicos, or water kefir, is a traditional fermented drink made with water and a symbiotic culture of bacteria and yeasts (SCOBY) held in a polysaccharide biofilm matrix created by the bacteria. It is sometimes consumed as an alternative to milk- ...

grains, used to make

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 ...

, but ''Lentilactobacillus'' species are responsible for the production of the

polysaccharide Polysaccharides (), or polycarbohydrates, are the most abundant carbohydrates found in food. They are long chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with wa ...

(

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 ...

and kefiran) that forms the grains. Major metabolites of ''L. brevis'' include

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 natu ...

and

ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl ...

. Strains of ''L. brevis'' and ''L. hilgardii'' have been found to produce the

biogenic amine A biogenic amine is a biogenic substance with one or more amine groups. They are basic nitrogenous compounds formed mainly by decarboxylation of amino acids or by amination and transamination of aldehydes and ketones. Biogenic amines are organic ...

tyramine Tyramine ( ) (also spelled tyramin), also known under several other names, is a naturally occurring trace amine derived from the amino acid tyrosine. Tyramine acts as a catecholamine releasing agent. Notably, it is unable to cross the blood-b ...

and phenylethylamine.

History

E.B.Fred, W.H. Peterson, and J.A. Anderson initially discovered the species in 1921 and the it was categorized based on the ability to metabolize certain carbon and sugars. This early study showed that this can produce acetic acid, carbon dioxide and large amounts of mannitol. Mannitol which is another carbon source that can be used to produce lactic acid.FRED, E.B., PETERSON,W.H., AND ANDERSON,J. A., J.Biol. Chem., 48, 385 (1921)

Growth

''L. brevis'' has been shown to actively transport

glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using ...

and

galactose Galactose (, '' galacto-'' + '' -ose'', "milk sugar"), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epimer of glucose. A galactose molec ...

. When

fructose Fructose, or fruit sugar, is a Ketose, ketonic monosaccharide, simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galacto ...

was used as a carbon source there was only some growth and ''L. brevis'' was able to partially metabolize the

mannitol Mannitol is a type of sugar alcohol used as a sweetener and medication. It is used as a low calorie sweetener as it is poorly absorbed by the intestines. As a medication, it is used to decrease pressure in the eyes, as in glaucoma, and to lo ...

. There are some strains that poorly metabolize glucose but prefer disaccharides as carbon source. By using the fermentation pathway the end result is lactic acid and acetic acid.Annuk, H., Shchepetova, J., Kullisaar, T., Songisepp, E., Zilmer, M., & Mikelsaar, M. (2003). Characterization of intestinal lactobacilli as putative probiotic candidates. Journal of Applied Microbiology, 94(3), 403-412. It appears that under high temperature conditions, 50 degrees Celsius and in acidic environments the survival of this bacteria is longer than most bacteria under acidic conditions, the bacteria can live about 45 minutes.Saarela, M., Rantala, M., Hallamaa, K., Nohynek, L., Virkajärvi, I., & Mättö, J. (2004). Stationary‐phase acid and heat treatments for improvement of the viability of probiotic lactobacilli and bifidobacteria. Journal of applied Science.

Antibiotic resistance Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistance. ...

is acquired through

conjugation Conjugation or conjugate may refer to: Linguistics * Grammatical conjugation, the modification of a verb from its basic form * Emotive conjugation or Russell's conjugation, the use of loaded language Mathematics * Complex conjugation, the chang ...

, a method of bacterial reproduction. Conjugation permits a sharing of DNA allowing the bacterium to learn about various antibiotics through exposure and this information is passed down through replication between bacteria.

''L. brevis'' produces more organic acids, specifically

acetic acid Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...

and

. This means that this bacterium produces an increased acidic environment and alcohol. Growth conditions all depend on the location of the bacterium within the intestines. It does seem that they are unable to significantly replicate in

anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: * Anaerobic adhesive, a bonding a ...

environments.

Metabolic pathway

Metabolic pathways are defined to mean the chemical process that occurs within an organism. ''L. brevis'' is heterofermentative and uses the phosphoketolase pathway to

metabolize Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...

pentoses and hexoses.

Food preservation

''L. brevis'' is found in food such as

and

. It is also one of the most common causes of

spoilage. The hop, which is an antimicrobial bitter flavoring agent in beer, fails to suppress some strains of L. brevis because they produce a transporter that pumps the active agents of hops out of the bacterial cell.Sami, M., Yamashita, H., Hirono, T., Kadokura, H., Kitamoto, K., Yoda, K., & Yamasaki, M. (1997). Hop-resistant ''Lactobacillus brevis'' contains a novel plasmid harboring a multidrug resistance-like gene. Journal of fermentation and bioengineering, 84(1), 1-6.Schmalreck, A. F., Teuber, M., Reininger, W., & Hartl, A. (1975). Structural features determining the antibiotic potencies of natural and synthetic hop bitter resins, their precursors and derivatives. Canadian Journal of Microbiology, 21(2), 205-212. ''L. brevis'' is one of the major

lactobacilli 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 ...

found in

grains (aka water kefir grains), and has been identified as the species responsible for the production of the

(

) that forms the grains. Major metabolites of ''L. brevis'' include

and

. Strains of ''L. brevis'' and ''L. hilgardii'' have been found to produce the

, which is found by the fermentation metabolic pathway and is commonly found in spoiled or fermented foods and phenylethylamine, which is found in chocolates but can also produce a fishy odor in other foods. Crushed hop

Microbial physiology

As a bacterium there are some physical attributes that are common for all bacteria.

Gram-positive bacteria 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 bact ...

consists of an external plasma membrane, followed by periplasmic space and finally a

peptidoglycan layer Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer outside the plasma membrane, the rigid cell wall (murein sacculus) characteristic of most ba ...

, which faces the interior of the bacteria. The external plasma membrane is very important for bacteria because this is how cells recognize the possible pathogenesis of the bacteria. Peptidoglycan is also called murein and is made up of a series of sugars. Within gram-positive bacteria the peptidoglycan layer is much thicker than gram-negative bacteria. The actual lattice that comprises peptidoglycan is referred to as the S-layer; this lattice is linked to the peptidoglycan layer. Unfortunately, the S-layer is normally lost when processing the bacteria under laboratory conditions, which can affect measuring adhesion. When the S-layer is dissolved with high concentration levels of substances that break down hydrogen bonds the S-layers have a survival time of about 20 minutes with each generation. ''L.brevis'' contains approximately two promoters within this area, meaning that there is significant

transcription Transcription refers to the process of converting sounds (voice, music etc.) into letters or musical notes, or producing a copy of something in another medium, including: Genetics * Transcription (biology), the copying of DNA into RNA, the fir ...

of the S-layer by high levels of transcribing of the sIpA gene.Sára, M., & Sleytr, U. B. (2000). S-layer proteins. Journal of Bacteriology, 182(4), 859-868. SipA is a gene that has been found to aid in the coding for the production of murin (peptidoglycan) within the bacteria. The purpose of transcription is to copy DNA into a mRNA, which is used to create proteins. The promoter is used during transcription to identify the appropriate location to begin transcribing. Within probiotics it is actually the S-layer that attaches to the cellular wall of the gastrointestinal tract Hyönen, U., Westerlund-Wikström, B., Palva, A. and Korhonen, T.K. (2002) Identification by flagellum display of an epithelial cell- and fibronectin-binding function in the SipA surface protein of ''Lactobacillus brevis''. Infect. Immun. 184, 3360–3367. Gram-positive cellwall-schematic

Probiotics

Ingestion of probiotics has been shown to improve human immune function, and ''L. brevis'' has been

ed several times. ''L. brevis'' has been shown to survive in the

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organ (biology), organs of the digestive syste ...

in humans and can therefore be used as a

probiotic Probiotics are live microorganisms promoted with claims that they provide health benefits when consumed, generally by improving or restoring the gut microbiota. Probiotics are considered generally safe to consume, but may cause bacteria-host i ...

. Currently the bacterium does not have the ability to convert milk to yogurt however, they are appropriate to be used as an alternative to other probiotics in yogurts. Within the

geriatric Geriatrics, or geriatric medicine, is a medical specialty focused on providing care for the unique health needs of older adults. The term ''geriatrics'' originates from the Greek language, Greek γέρων ''geron'' meaning "old man", and ιατ ...

population use of the bacteria in milk has been shown to increase cellular immunity. Dietary probiotic supplementation enhances natural killer cell activity in the elderly (an investigation of age-related immunological changes). ''L. brevis'' is considered appropriate for probiotic use because there is significant growth at pH's 4–5, pH 5 is normally the appropriate range for milk and yogurts.

Biotherapies

There are significant vaginal bacteria that are found within the vagina and ''L. brevis'' is included in this microbiome, which is a collection of various bacteria. The bacteria collaborate on protecting the vagina and vaginal maintenance. Women of childbearing ages have a significant amount of ''L.brevis'' and this is normally found in a healthy vagina.Vásquez, A., Jakobsson, T., Ahrné, S., Forsum, U., & Molin, G. (2002). Vaginal ''Lactobacillus'' flora of healthy Swedish women. Journal of Clinical Microbiology, 40(8), 2746-2749. For some illnesses or disruptions of the vagina this bacteria can be used in aiding to restore the microbiome. Most

have been found useful in preventing urinary tract infections. The efficiency in which a bacterium can defend the body is:Raz, R., & Stamm, W. E. (1993). A controlled trial of intravaginal estriol in postmenopausal women with recurrent urinary tract infections. New England Journal of Medicine, 329(11), 753-756. # Their symbiosis with potential pathogens. # Their capability of producing antibacterial materials, such as hydrogen peroxide, to limit pathogen growth. # Their production of biosurfactants that inhibit pathogen adherence. # Their ability to prime macrophages, leukocytes, cytokines, and other host defenses. During normal childbirth, it appears that newborns after a period of days receive transmission of ''L. brevis'' from the mother. It appears that the transmission occurs through breast feeding or through natural child birth.Matsumiya, Y., Kato, N., Watanabe, K., & Kato, H. (2002). Molecular epidemiological study of vertical transmission of vaginal ''Lactobacillus'' species from mothers to newborn infants in Japanese, by arbitrarily primed polymerase chain reaction. Journal of Infection and chemotherapy, 8(1), 43-49. In infants, this resistance is also helpful with protecting the gut against various bile and acids. ''

Helicobacter pylori ''Helicobacter pylori'', previously known as ''Campylobacter pylori'', is a gram-negative, microaerophilic, spiral (helical) bacterium usually found in the stomach. Its helical shape (from which the genus name, helicobacter, derives) is though ...

,'' which is a common gut pathogen in humans, studies have shown that certain strains of ''L. brevis'' are successful at combating this pathogen.

Vaginosis Bacterial vaginosis (BV) is a disease of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urination ...

is the most common form of bacterial infection this is commonly diagnosed as a yeast infection or

trichomoniasis Trichomoniasis (trich) is an infectious disease caused by the parasite ''Trichomonas vaginalis''. About 70% of affected people do not have symptoms when infected. When symptoms occur, they typically begin 5 to 28 days after exposure. Symptoms ca ...

, which is a sexually transmitted parasite commonly acquired during intercourse. ''L. brevis'' along with '' Lactobacillus jensenii'' has been shown to produce high levels of hydrogen peroxide which may be able remediate the bacterial vaginosis pathogenesis.Eschenbach, D. A., Davick, P. R., Williams, B. L., Klebanoff, S. J., Young-Smith, K., Critchlow, C. M., & Holmes, K. K. (1989). Prevalence of hydrogen peroxide-producing ''Lactobacillus'' species in normal women and women with bacterial vaginosis. Journal of Clinical Microbiology, 27(2), 251-256.''L. Brevis'' is a commonly used ingredient in pharmaceutical materials used to treat

vaginosis Bacterial vaginosis (BV) is a disease of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urination ...

. An evaluation of clue cells is one method of assessing vaginosis; this assessment is performed by mounting clue cells and vaginal discharge onto a slide then adding sodium chloride followed by a microscopic assessment which involves bacteria identification. In addition to surviving within the gut of an organism, ''L. brevis'' can also act to inhibit the pathogenic effects of certain gut pathogens and can also proliferate in the presence of additional bacteria. Some strains are resistant to certain

antibiotics An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention o ...

, specifically

erythromycin Erythromycin is an antibiotic used for the treatment of a number of bacterial infections. This includes respiratory tract infections, skin infections, chlamydia infections, pelvic inflammatory disease, and syphilis. It may also be used duri ...

and

clindamycin Clindamycin is an antibiotic medication used for the treatment of a number of bacterial infections, including osteomyelitis (bone) or joint infections, pelvic inflammatory disease, strep throat, pneumonia, acute otitis media (middle ear infec ...

.Delgado, S., Flórez, A. B., & Mayo, B. (2005). Antibiotic susceptibility of ''Lactobacillus'' and ''Bifidobacterium'' species from the human gastrointestinal tract. Current Microbiology, 50(4), 202-207. This antibiotic resistance may be helpful in maintaining a healthy gut microbiome when taking prescribed antibiotics. Clue cells - CDC PHIL 3720

References

* * *Jayaram, S., Castle, G. S. P., & Margaritis, A. (2004). Kinetics of sterilization of ''Lactobacillus brevis'' cells by the application of high voltage pulses. Biotechnology and Bioengineering, 40(11), 1412–1420. *Drago, L., Gismondo, M.R., Lombardi, A., de Haën, C. and Gozzini, L. (1997) Inhibition of ''in vitro'' growth of enteropathogens by new ''Lactobacillus'' isolates of human intestinal origin. FEMS Microbioloy Letters 153, 455–463 *Gill, H. S., Rutherfurd, K. J., & Cross, M. L. (2001). Dietary probiotic supplementation enhances natural killer cell activity in the elderly: an investigation of age-related immunological changes. Journal of clinical immunology, 21(4), 264-271

External links

Type strain of ''Lactobacillus brevis'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
{{Taxonbar, from=Q559395 Lactobacillaceae Food science Dietary supplements