''Lacticaseibacillus rhamnosus'' (previously ''Lactobacillus rhamnosus'') is a

bacterium 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 among ...

that originally was considered to be a subspecies of ''

L. casei ''Lacticaseibacillus casei ''is an organism that belongs to the largest genus in the family ''Lactobacillaceae'', a lactic acid bacteria (LAB), that was previously classified as ''Lactobacillus casei-01''. This bacteria has been identified as facu ...

'', but genetic research found it to be a separate species in the ''L. casei'' clade, which also includes ''

L. paracasei Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

'' and ''L. zeae''. It is a short

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 ...

homofermentative

facultative anaerobic A facultative anaerobic organism is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation if oxygen is absent. Some examples of facultatively anaerobic bacteria are '' Staphylococc ...

non-spore-forming rod that often appears in chains. Some strains of ''L. rhamnosus'' bacteria are being used as

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 ...

s, and are particularly useful in treating infections of the female urogenital tract, most particularly very difficult to treat cases of

bacterial 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 ...

(or "BV"). The species ''Lacticaseibacillus rhamnosus'' and '' Limosilactobacillus reuteri'' are commonly found in the healthy female genito-urinary tract and are helpful to regain control of dysbiotic bacterial overgrowth during an active infection. ''L. rhamnosus'' sometimes is used in

dairy product Dairy products or milk products, also known as lacticinia, are food products made from (or containing) milk. The most common dairy animals are cow, water buffalo, nanny goat, and ewe. Dairy products include common grocery store food items in th ...

s such as fermented milk and as non-starter-lactic acid bacterium (NSLAB) in long-ripened cheese. While frequently considered a beneficial organism, ''L. rhamnosus'' may not be as beneficial to certain subsets of the population; in rare circumstances, especially those primarily involving

weakened immune system Immunodeficiency, also known as immunocompromisation, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that a ...

or infants, it may cause

endocarditis Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves. Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or the ...

. Despite the rare infections caused by ''L. rhamnosus'', the species is included in the list of bacterial species with qualified presumed safety (QPS) status of the

European Food Safety Agency The European Food Safety Authority (EFSA) is the agency of the European Union (EU) that provides independent scientific advice and communicates on existing and emerging risks associated with the food chain. EFSA was established in February 2002, ...

Genome

''Lacticaseibacillus rhamnosus'' is considered a nomadic organism and strains have been isolated from many different environments including the vagina and the gastrointestinal tract. ''L. rhamnosus'' strains have the capacity for strain-specific gene functions that are required to adapt to a large range of environments. Its core

genome In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ge ...

contains 2,164 genes, out of 4,711 genes in total (the

pan-genome In the fields of molecular biology and genetics, a pan-genome (pangenome or supragenome) is the entire set of genes from all strains within a clade. More generally, it is the union of all the genomes of a clade. The pan-genome can be broken d ...

). The accessory genome is overtaken by genes encoding carbohydrate transport and metabolism, extracellular polysaccharides,

biosynthesis Biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. ...

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 ...

production, pili production, the CRISPR-Cas system, the clustered regularly interspaced short palindromic repeat (

CRISPR CRISPR () (an acronym for clustered regularly interspaced short palindromic repeats) is a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea. These sequences are derived from DNA fragments of bacte ...

) loci, and more than 100 transporter functions and mobile genetic elements such as

phages A bacteriophage (), also known informally as a ''phage'' (), is a duplodnaviria virus that infects and replicates within bacteria and archaea. The term was derived from "bacteria" and the Greek φαγεῖν ('), meaning "to devour". Bacterio ...

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 ...

genes, and

transposon A transposable element (TE, transposon, or jumping gene) is a nucleic acid sequence in DNA that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transpo ...

s. The genome of the specific strain ''L. rhamnosus'' LRB, in this case, taken from a human baby tooth, consists of a circular chromosome of 2,934,954 bp with 46.78% GC content. This genome contains 2,749 total genes with 2,672 that are total protein-coding sequences. This sample did not contain any plasmids. The most extensively studied strain, ''L. rhamnosus'' GG, a gut isolate, consists of a genome of 3,010,111 bp. Therefore, the LRB genome is shorter than GG’s genome. LRB lacks the spaCBA gene cluster of GG and is not expected to produce functional pili (6). This difference may help explain why each strain lives in a different habitat.

''Lacticaseibacillus rhamnosus GG'' (ATCC 53103)

''Lacticaseibacillus rhamnosus'' GG (ATCC 53103) is a

strain Strain may refer to: Science and technology * Strain (biology), variants of plants, viruses or bacteria; or an inbred animal used for experimental purposes * Strain (chemistry), a chemical stress of a molecule * Strain (injury), an injury to a mu ...

of ''L. rhamnosus'' that was isolated in 1983 from the intestinal tract of a healthy human being; filed for a patent on 17 April 1985, by

Sherwood Gorbach Sherwood Leslie Gorbach (born 1934) is an Emeritus Professor at Tufts University School of Medicine. He was editor-in-chief of the journal ''Clinical Infectious Diseases'' from 2000 to 2016. Education He graduated from Brandeis University in 1955, ...

and Barry Goldin, the 'GG' derives from the first letters of their surnames. The patent refers to a strain of "''L. acidophilus'' GG" with

American Type Culture Collection ATCC or the American Type Culture Collection is a nonprofit organization which collects, stores, and distributes standard reference microorganisms, cell lines and other materials for research and development. Established in 1925 to serve as a natio ...

(ATCC) accession number 53103; later reclassified as a strain of ''L. rhamnosus''. The patent claims the ''L. rhamnosus'' GG (ATCC 53103) strain is acid- and bile-stable, has a great

avidity In biochemistry, avidity refers to the accumulated strength of ''multiple'' affinities of individual non-covalent binding interactions, such as between a protein receptor and its ligand, and is commonly referred to as functional affinity. Avidity di ...

for human intestinal mucosal cells, and produces

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 ...

. Since the discovery of the ''L. rhamnosus'' GG (ATCC 53103) strain, it has been studied extensively on its various health benefits and currently ''L. rhamnosus'' GG (ATCC 53103) strain is the world's most studied probiotic bacterium with more than 800 scientific studies. The genome sequence of ''Lactobacillus rhamnosus'' GG (ATCC 53103) has been decoded in 2009.

History

In 1983, ''L. rhamnosus'' GG was isolated from the intestinal tract of a healthy human by Sherwood Gorbach and Barry Goldin.

Medical research and use

While ''L. rhamnosus'' GG (ATCC 53103) is able to survive the acid and bile of the stomach and intestine, is claimed to colonize the digestive tract, and to balance intestinal microbiota, evidence suggests that ''L. rhamnosus'', comparable to virtually all probiotic lactobacilli, is only a transient inhabitant and not

autochthonous Autochthon, autochthons or autochthonous may refer to: Fiction * Autochthon (Atlantis), a character in Plato's myth of Atlantis * Autochthons, characters in the novel ''The Divine Invasion'' by Philip K. Dick * Autochthon, a Primordial in the ' ...

. ''Lactobacillus rhamnosus'' GG binds to the gut mucosa. These features make it a favorable organism for the investigation of probiotic supplementation as a potential treatment for a variety of disease states. No studies to date have identified illnesses for which a probiotic organism is an appropriate first- or second-line treatment.

Diarrhea

''Lacticaseibacillus rhamnosus'' GG is beneficial in the prevention of

rotavirus ''Rotavirus'' is a genus of double-stranded RNA viruses in the family ''Reoviridae''. Rotaviruses are the most common cause of diarrhoeal disease among infants and young children. Nearly every child in the world is infected with a rotavirus a ...

diarrhea Diarrhea, also spelled diarrhoea, is the condition of having at least three loose, liquid, or watery bowel movements each day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin wi ...

in children. Prevention and treatment of various types of

have been shown in children and in adults. ''L. rhamnosus'' GG can be beneficial in the prevention of antibiotic-associated diarrhea and nosocomial diarrhea and this has been recently supported by European guidelines. ''Lactobacillus rhamnosus'' GG may reduce the risk of traveler's diarrhea.

Acute gastroenteritis

A position paper published by ESPGHAN Working Group for Probiotics and Prebiotics based on a systematic review and

randomized controlled trials A randomized controlled trial (or randomized control trial; RCT) is a form of scientific experiment used to control factors not under direct experimental control. Examples of RCTs are clinical trials that compare the effects of drugs, surgical te ...

(RCTs) suggested that ''L. rhamnosus'' GG (low quality of evidence, strong recommendation) may be considered in the management of children with acute

gastroenteritis Gastroenteritis, also known as infectious diarrhea and gastro, is an inflammation of the gastrointestinal tract including the stomach and intestine. Symptoms may include diarrhea, vomiting, and abdominal pain. Fever, lack of energy, and dehydra ...

in addition to

rehydration therapy The management of dehydration typically involves the use of Oral rehydration therapy, oral rehydration solution (ORS). Standard home solutions such as salted rice water, salted yogurt drinks, vegetable and chicken soups with salt can be given. Hom ...

Atopic dermatitis, eczema

''Lacticaseibacillus rhamnosus'' GG has been found to be ineffective for treating eczema. However in one non-randomized clinical observation dealing with resistant childhood atopic eczema, a substantial improvement in quality of life was reported in pediatric patients given Lactobacillus rhamnosus as a supplement.

Risks

The use of ''L. rhamnosus'' GG for

therapy has been linked with rare cases of

sepsis Sepsis, formerly known as septicemia (septicaemia in British English) or blood poisoning, is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage is follo ...

in certain risk groups, primarily those with a

and infants. Ingestion of GG is considered to be safe and data show a significant growth in the consumption of ''L. rhamnosus'' GG at the population level did not lead to an increase in ''Lactobacillus''

bacteraemia Bloodstream infections (BSIs), which include bacteremias when the infections are bacterial and fungemias when the infections are fungal, are infections present in the blood. Blood is normally a sterile environment, so the detection of micro ...

cases.

''Lacticaseibacillus rhamnosus'' GR-1

''Lacticaseibacillus rhamnosus'' GR-1 was originally found in the urethra of a healthy female and is nowadays a model strain for vaginal probiotics. A genome comparison between ''L. rhamnosus'' GG and ''L. rhamnosus'' GR-1 shows that GR-1 lacks ''spaCBA''-encoded pili, an important adhesin in ''L. rhamnosus'' GG adhesion to the intestinal epithelial cells. In contrast, ''L. rhamnosus'' GR-1 utilises

lectin Lectins are carbohydrate-binding proteins that are highly specific for sugar groups that are part of other molecules, so cause agglutination of particular cells or precipitation of glycoconjugates and polysaccharides. Lectins have a role in rec ...

-like proteins to attach to carbohydrates on the surface of the target cell. Lectin-like proteins preferentially bind to nonkeratinized stratified squamous cells which are found in the urethra and vagina. The lectin-like protein 1 purified from ''L. rhamnosus'' GR-1 is found to prevent infection by the uropathogenic ''E. coli'' UTI89 by inhibiting its adhesion to epithelial cells and by disrupting its

biofilm A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular ...

formation. Additionally, it can increase biofilm formation in other beneficial lactobacilli that inhabit the vagina.

References

External links

Type strain of ''Lactobacillus rhamnosus'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
{{Taxonbar, from=Q1607640 Digestive system Probiotics Lactobacillaceae Bacteria described in 1989