science

Duplodnaviria

Duplodnaviria 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 Duplodnaviria rather than just read about it. In short: Duplodnaviria is a realm of viruses that includes all double-stranded DNA viruses that encode the HK97 fold major capsid protein. The HK97 fold major capsid protein (HK97 MCP) is the primary component of the viral capsid, which stores the viral deoxyribonucleic acid (DNA).

Key takeaways

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

Reference excerpt

Duplodnaviria is a realm of viruses that includes all double-stranded DNA viruses that encode the HK97 fold major capsid protein. The HK97 fold major capsid protein (HK97 MCP) is the primary component of the viral capsid, which stores the viral deoxyribonucleic acid (DNA). Viruses in the realm also share a number of other characteristics, such as an icosahedral capsid, an opening in the capsid called a portal, a protease enzyme that empties the inside of the capsid prior to DNA packaging, and a terminase enzyme that packages viral DNA into the capsid. There are three groups of viruses in the realm: caudoviruses, herpesviruses, and the putative group mirusviruses. Caudoviruses are one of the most abundant group of viruses on Earth and are ubiquitous worldwide. They infect prokaryotes and are a major cause of death in them, which contributes to the recycling of organic material in a process called viral shunt. Caudoviruses have been used as model organisms to study biological processes and as a form of therapy to treat bacterial infections. Herpesviruses infect animals and are commonly associated with diseases such as herpes and chickenpox. Mirusviruses infect microscopic eukaryotes and are among the most common eukaryotic viruses in sunlit oceans. Many duplodnavirians are able to enter a latent state in which they persist in cells without forming virions, called the lysogenic cycle. Duplodnaviria likely predates the last universal common ancestor (LUCA) of cellular life and was present in the LUCA. Caudoviruses in particular were likely already diverse by the time the LUCA emerged. Mirusviruses are related to viruses in the phylum Nucleocytoviricota in the realm Varidnaviria because they encode the core replication- and transcription-related proteins found in nucleocytoviruses. It is unclear, however, which realm these genes originate from. In any case, herpesviruses appear to have lost most of these genes through reductive evolution. Outside the realm, an HK97-like fold is only found in encapsulins, which form nanocompartments in prokaryotes and are likely derived from duplodnaviruses.

Classification Duplodnaviria contains one kingdom, which is divided into two phyla that contain two lineages of viruses in the realm: caudoviruses and herpesviruses. This can be visualized as follows:

Realm: Duplodnaviria Kingdom: Heunggongvirae Phylum: Peploviricota Class: Herviviricetes Order: Herpesvirales – herpesviruses, which infect animals (eukaryotes) Phylum: Uroviricota Class: Caudoviricetes – caudoviruses, also called head-tail viruses and tailed viruses, which infect archaea and bacteria (prokaryotes) The realm also contains mirusviruses, which have not been assigned to any taxon officially but which constitute the putative phylum Mirusviricota. As all viruses in the realm are double-stranded DNA (dsDNA) viruses, the realm belongs to Group I: dsDNA viruses of Baltimore classification, a classification system based on a virus's manner of messenger RNA (mRNA) production that is often used alongside standard virus taxonomy, which is based on evolutionary history. Realms are the highest level of taxonomy used for viruses and Duplodnaviria is one of ten. The others are Adnaviria, Efunaviria, Floreoviria, Pleomoviria, Riboviria, Ribozyviria, Singelaviria, Varidnaviria, and Volvereviria.

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with Duplodnaviria

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

In research: Duplodnaviria 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 Duplodnaviria 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: Duplodnaviria is common in secondary-school and first-year university syllabi. It links to neighbouring topics Virus realms, Viruses, so understanding it makes those chapters shorter.
In everyday life: Look for Duplodnaviria 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 “Duplodnaviria” →

Affiliate

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

How to study Duplodnaviria in 20 minutes

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

Frequently asked questions

What is Duplodnaviria in simple terms?

Why does Duplodnaviria 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 Duplodnaviria?

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 Duplodnaviria.