science

Lacticaseibacillus rhamnosus

Lacticaseibacillus rhamnosus is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Lacticaseibacillus rhamnosus rather than just read about it. In short: Lacticaseibacillus rhamnosus (previously Lactobacillus rhamnosus) is a bacterium that originally was considered to be a subspecies of L. casei, but genetic research found it to be a separate species in the L. casei clade, which also includes L. paracasei and L. zeae. It is a short Gram-positive homofermentative facultative anaerobic non-spore-forming rod that often appears in chains.

Key takeaways

Lacticaseibacillus rhamnosus belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Lacticaseibacillus rhamnosus to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Lacticaseibacillus rhamnosus from memory before moving on to harder problems.

Reference excerpt

Lacticaseibacillus rhamnosus (previously Lactobacillus rhamnosus) is a bacterium that originally was considered to be a subspecies of L. casei, but genetic research found it to be a separate species in the L. casei clade, which also includes L. paracasei and L. zeae. It is a short Gram-positive homofermentative facultative anaerobic non-spore-forming rod that often appears in chains. Some strains of L. rhamnosus bacteria are being used as probiotics, and are particularly useful in treating infections of the female urogenital tract, most particularly very difficult to treat cases of bacterial vaginosis (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 products 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 or infants, it may cause endocarditis. 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.

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 contains 2,164 genes, out of 4,711 genes in total (the pan-genome). The accessory genome is overtaken by genes encoding carbohydrate transport and metabolism, extracellular polysaccharides, biosynthesis, bacteriocin production, pili production, the CRISPR-Cas system, the clustered regularly interspaced short palindromic repeat (CRISPR) loci, and more than 100 transporter functions and mobile genetic elements such as phages, plasmid genes, and transposons. 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 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 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) 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 for human intestinal mucosal cells, and produces lactic acid. 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. 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.

Diarrhea Lacticaseibacillus rhamnosus GG is beneficial in the prevention of rotavirus diarrhea in children. Prevention and treatment of various types of diarrhea 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 (RCTs) suggested that L. rhamnosus GG (low quality of evidence, strong recommendation) may be considered in the management of children with acute gastroenteritis in addition to rehydration therapy.

Atopic dermatitis, eczema Lacticaseibacillus rhamnosus GG is 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 Lacticaseibacillus rhamnosus rhamnosus as a supplement.

Risks The use of L. rhamnosus GG for probiotic therapy has been linked with rare cases of sepsis in certain risk groups, primarily those with a weakened immune system 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 cases.

Lacticaseibacillus rhamnosus GR-1

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with Lacticaseibacillus rhamnosus

Start with the simplest possible case. Write down what Lacticaseibacillus rhamnosus claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Lacticaseibacillus rhamnosus before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Lacticaseibacillus rhamnosus ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Lacticaseibacillus rhamnosus

In research: Lacticaseibacillus rhamnosus appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Lacticaseibacillus rhamnosus in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Lacticaseibacillus rhamnosus is common in secondary-school and first-year university syllabi. It links to neighbouring topics Bacteria described in 1989, Digestive system, Lactobacillaceae, so understanding it makes those chapters shorter.
In everyday life: Look for Lacticaseibacillus rhamnosus outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Lacticaseibacillus rhamnosus” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Lacticaseibacillus rhamnosus in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Lacticaseibacillus rhamnosus means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Lacticaseibacillus rhamnosus out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Lacticaseibacillus rhamnosus in simple terms?

Why does Lacticaseibacillus rhamnosus matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Lacticaseibacillus rhamnosus?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Lacticaseibacillus rhamnosus.