Tomasiella immunophila

Key takeaways

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

Reference excerpt

Tomasiella immunophila is a gram-negative bacterium that was found in the gut of mice. It is believed to be able to break down SIgA. It is hypothesized to be the root of Inflammatory bowel disease and other immunodeficient issues. The genus Tomasiella is named after the late Dr. Thomas Tomasi, a scientist who discovered Secretory Immunoglobulin A (SIgA), an essential part of the immune system. The name is combined with the latin suffix "-ella", meaning extremely small. The species name immunophila comes from the prefix "immuno-" for the immune system, and the Greek word "-philos", meaning "loving". It was chosen because of the bacteria's ability to interact with the immune system by breaking down SIgA, which causes immunodeficiency, or weakened bodily defenses...

Classification

Taxonomy Tomasiella immunophila is part of the Muribaculaceae family, which is in the order Bacteroidales. It was first grouped as part of the genus CAG-873, until later studies placed it in its own genus, Tomasiella. Although not much is known yet, current research suggests that T. immunophila doesn't seem to cause much harm. The Muribaculaceae family includes symbiotic bacteria that live in the intestines of mice, where they survive without oxygen as anaerobic bacteria

Relatives Within its order (Bacteriodales), T. immunophila is most similar to a species called Tannerella forsythia. Both bacteria require a special compound called MurNAc to help build their cell walls because of their auxotrophy - a mutation that prevents their growth. Within the Muribaculaceae family, T. immunophila is closely related to two species: Duncaniella dubosii and Muribaculum intestinale

Morphology Tomasiella immunophila is a type of gram-negative bacteria, meaning it has a thin cell wall with an outer membrane made up of special molecules called lipopolysaccharides. However, T. immunophila have cell wall auxotrophy, meaning that they are missing an important part to fully be able to build their cell wall. Therefore, they have to get it from an outside source, in the form of the compound MurNAc. Due to this auxotrophy, they are irregularly shaped, with no established cellular morphology (a cell's shape, size, and appearance). However, it takes on a rod-like shape (bacillus) when grown with N-acetylmuramic acid (MurNAc), since its missing the enzymes (MurA, MurB, and GlmS) that other bacteria use to make MurNAc on their own.

Discovery An article was released September 2024 discussing a new discovery made by Thaddeus Stappenbeck and Qiuhe Lu, who led the research project at Cleveland Clinic. The research was based on identifying what is responsible for SIgA breakdown. SIgA, or secretory immunoglobulin A, is an important component of the gut mucosal barrier that is responsible for protection of the gut against infections and pathogens. If SIgA were to decrease in levels, there is a higher risk of infection, inflammation, and illness. The researchers utilized next-generation sequencing which is a form of being able to determine the sequence of DNA by separating into smaller fragments. This procedure was performed on mice with low and high levels of SIgA. The feces of mice are collected and then the sample is cultured anaerobically, in an environment that does not contain oxygen. The cultured samples were tested using various agars, antibiotics, and tests to confirm the break down of SIgA which is when the unknown bacteria strain was confirmed as a separate group. The various microorganisms were determined using 16S ribosomal RNA gene amplicon sequencing which is a process of identifying the bacteria using a genetic marker. The organisms found in the mices' feces were Allobaculum, Sutterella, Clostridiaceae, Muribaculaceae and an unknown strain. By using a genome taxonomy database toolkit, an identification tool, the unknown bacteria was determined to be another relative to the Muribaculaceae. The bacteria was named Tomasiella immunophila. Tomasiella immunophila underwent fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR). The goal of FISH is to detect desired genes and/or gene sequences while the goal of PCRs is to multiply a specific gene sequence so it can be further analyzed and studied. The bacteria is present throughout the gastrointestinal tract but was pinpointed to mainly be concentrated in the cecum and colon In vitro assays showed Tomasiella immunophila was able to degrade other immunoglobulin compounds like IgA, IgM, and IgE, which are different types of antibodies in our immune system. The only immunoglobulin left untouched was IgG. Tomasiella immunophila degradation factors were found due to scanning electron microscopy which is a way to magnify the organism's surface to be able to see it and analyze it. This procedure revealed multiple outer membrane vesicles which are small sacs that carry various bacterial components. In the presence of Tomasiella immunophila, the mice immune system began secreting antibodies specific to the bacterium. With a generally weakened mucosal barrier, the mice were immunodeficient and were unable to repair their defense barriers when faced with dextran sulfate sodium-induced injury (a way to simulate inflammatory bowel disease)

Genomics Tomasiella immunophila was discovered to have special metabolic genes that let it use the compound MurNAc and add it to its peptidoglycan layer, an important part of the inner cell wall that helps it keep its shape. This helps the bacteria build its cell wall even though it can't make MurNAc on its own. Comparing its DNA to that of related bacteria, T. immunophila was also found to have multiple, unique proteases, which are enzymes that help break down other proteins. 16s rRNA gene sequencing, a method to identify and tell different types of bacteria apart, allowed both the identification of other bacteria related to T. immunophila, and its original classification under the genus CAG-873. Using the strain DCM001, whole-genome sequencing - a method to sequence a species' entire genome - was made possible, allowing them to correctly place it in its own genus, Tomasiella. It revealed that its genomic DNA has a G+C content of 50.93% and includes exactly 190 enzymes that help break down carbohydrates. Its entire linear DNA is made up of 3,637,252 base pairs (bp)

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Worked examples

Example 1 — a first encounter with Tomasiella immunophila

Start with the simplest possible case. Write down what Tomasiella immunophila claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, 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 Tomasiella immunophila 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 Tomasiella immunophila 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 Tomasiella immunophila

In research: Tomasiella immunophila appears in biology 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 Tomasiella immunophila 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: Tomasiella immunophila is common in secondary-school and first-year university syllabi. It links to neighbouring topics Bacteroidia, Gram-negative bacteria, Undescribed species, so understanding it makes those chapters shorter.
In everyday life: Look for Tomasiella immunophila 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.

How to study Tomasiella immunophila in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Tomasiella immunophila 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 Tomasiella immunophila out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Tomasiella immunophila in simple terms?

Tomasiella immunophila is a gram-negative bacterium that was found in the gut of mice. It is believed to be able to break down SIgA.

Why does Tomasiella immunophila matter?

Because it connects several biology 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 Tomasiella immunophila?

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 Tomasiella immunophila.