Nanobdellati

Key takeaways

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

Reference excerpt

Nanobdellati (syn. "DPANN") is a kingdom of archaea first proposed in 2013. Many members show novel signs of horizontal gene transfer from other domains of life. They are known as nanoarchaea or ultra-small archaea due to their smaller size (nanometric) compared to other archaea. "DPANN" is an acronym formed by the initials of the first five groups discovered: Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota and Nanohaloarchaeota. Later Woesearchaeota and Pacearchaeota were discovered and proposed within the "DPANN" superphylum. In 2017, another phylum Altiarchaeota was placed into the "DPANN" superphylum. The monophyly of Nanobdellati is not yet considered established, due to the high mutation rate of the included phyla, which can lead to the artifact of the long branch attraction (LBA) where the lineages are grouped basally or artificially at the base of the phylogenetic tree without being related. These analyses instead suggest that Nanobdellati belongs to Euryarchaeota or is polyphyletic occupying various positions within Euryarchaeota. The Nanobdellati groups together different phyla with a variety of environmental distribution and metabolism, ranging from symbiotic and thermophilic forms such as Nanoarchaeota, acidophiles like Parvarchaeota and non-extremophiles like Aenigmarchaeota and Diapherotrites. Nanobdellati was also detected in nitrate-rich groundwater, on the water surface but not below, indicating that these taxa are still quite difficult to locate. Since the recognition of the kingdom rank by the ICNP, the only validly published name for this group is kingdom Nanobdellati.

Characteristics They are characterized by being small in size compared to other archaea (nanometric size) and in keeping with their small genome, they have limited but sufficient catabolic capacities to lead a free life, although many are thought to be episymbionts that depend on a symbiotic or parasitic association with other organisms. Many of their characteristics are similar or analogous to those of ultra-small bacteria (CPR group). Limited metabolic capacities are a product of the small genome and are reflected in the fact that many lack central biosynthetic pathways for nucleotides, aminoacids, and lipids; hence most Nanobdellati archaea, such as ARMAN archaea, which rely on other microbes to meet their biological requirements. But those that have the potential to live freely are fermentative and aerobic heterotrophs. They are mostly anaerobic and have not been cultivated. They live in extreme environments such as thermophilic, hyperacidophilic, hyperhalophilic or metal-resistant; or also in the temperate environment of marine and lake sediments. They are rarely found on the ground or in the open ocean.

Classification Diapherotrites. Found by phylogenetic analysis of the genomes recovered from the groundwater filtration of a gold mine abandoned in the USA. Parvarchaeota and Micrarchaeota. Discovered in 2006 in acidic mine drainage from a US mine. They are of very small size and provisionally called ARMAN (Archaeal Richmond Mine acidophilic nanoorganisms). Woesearchaeota and Pacearchaeota. They have been identified both in sediments and in surface waters of aquifers and lakes, abounding especially in saline conditions. Aenigmarchaeota. Found in wastewater from mines and in sediments from hot springs. Nanohalarchaeota. Distributed in environments with high salinity. Nanoarchaeota. They were the first discovered (in 2002) in a hydrothermal source next to the coast of Iceland. They live as symbionts of other archaea.

Phylogeny

Taxonomy

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI).

Kingdom Nanobdellati Rinke et al. 2013

Phylum Microcaldota Sakai et al. 2023 Class Microcaldia Sakai et al. 2023 Order ?Microcaldales Sakai et al. 2023 Phylum "Undinarchaeota" Dombrowski et al. 2020 Class "Undinarchaeia" Dombrowski et al. 2020 Order "Undinarchaeales" Dombrowski et al. 2020 Phylum Altarchaeota Probst et al. 2018 (SM1) Class "Altarchaeia" corrig. Probst et al. 2014 Order "Altarchaeales" corrig. Probst et al. 2014 Phylum "Iainarchaeota" corrig. Rinke et al. 2013 ["Diapherotrites" Rinke et al. 2013] (DUSEL-3) Class "Iainarchaeia" Rinke et al. 2020 Order "Forterreales" Probst & Banfield 2017 Order "Iainarchaeales" Rinke et al. 2020 Phylum "Micrarchaeota" Baker & Dick 2013 Class "Micrarchaeia" Vazquez-Campos et al. 2021 Order "Anstonellales" Vazquez-Campos et al. 2021 (LFWA-IIIc) Order "Burarchaeales" Vazquez-Campos et al. 2021 ["Fermentimicrarchaeales" Kadnikov et al. 2020; "Gugararchaeales" Vazquez-Campos et al. 2021] (LFWA-IIIa, LFWA-IIIb) Order "Micrarchaeales" Vazquez-Campos et al. 2021 Order "Norongarragalinales" Vazquez-Campos et al. 2021 (LFWA-II) Phylum "Huberarchaeota" Probst et al. 2019 Class "Huberarchaeia" corrig. Probst et al. 2019 Order "Huberarchaeales" Rinke et al. 2020 Phylum "Aenigmatarchaeota" corrig. Rinke et al. 2013 (DSEG, DUSEL2) Class "Aenigmatarchaeia" corrig. Rinke et al. 2020 Order "Aenigmatarchaeales" corrig. Rinke et al. 2020 Order PWEA01 Phylum "Terrarchaeota" Hamm et al. 2026 [EX4484-52] Class "Terrarchaeia" Hamm et al. 2026 Order "Terrarchaeales" Hamm et al. 2026 Phylum "Nanohalarchaeota" corrig. Rinke et al. 2013 Class "Nanohalobiia" corrig.La Cono et al. 2020 Order "Nanohalobiales" La Cono et al. 2020 Class "Nanohalarchaeia" corrig. Narasingarao et al. 2012 Order ?"Nanohalarchaeales" Order ?"Nanohydrothermales" Xie et al. 2022 Order ?"Nucleotidisoterales" Xie et al. 2022 Phylum Nanobdellota Huber et al. 2023 Class Nanobdellia Kato et al. 2022 Order JAPDLS01 Order "Jingweiarchaeales" Rao et al. 2023 [DTBS01] Order Nanobdellales Kato et al. 2022 Order "Pacearchaeales" (DHVE-5, DUSEL-1) Order "Parvarchaeales" Rinke et al. 2020 (ARMAN 4 & 5) Order "Tiddalikarchaeales" Vazquez-Campos et al. 2021 (LFW-252_1) Order "Woesearchaeales" (DHVE-6) Phylum ?"Mamarchaeota" Order ?"Wiannamattarchaeales"

Illustrations

Worked examples

Example 1 — a first encounter with Nanobdellati

Start with the simplest possible case. Write down what Nanobdellati 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 Nanobdellati 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 Nanobdellati 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 Nanobdellati

In research: Nanobdellati 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 Nanobdellati 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: Nanobdellati is common in secondary-school and first-year university syllabi. It links to neighbouring topics Archaea kingdoms, Extremophiles, so understanding it makes those chapters shorter.
In everyday life: Look for Nanobdellati 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 Nanobdellati in 20 minutes

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

Frequently asked questions

What is Nanobdellati in simple terms?

Nanobdellati (syn. "DPANN") is a kingdom of archaea first proposed in 2013. Many members show novel signs of horizontal gene transfer from other domains of life.

Why does Nanobdellati 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 Nanobdellati?

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 Nanobdellati.