Detecting giant viruses raises the question of what is life?

Although it is well-known in the media about its infectious ability and death, but in modern biological definition, virus is not considered a living organism like bacteria, animals, plants.

In the spirit of modern biology, an object is considered "alive" when it has the ability to grow in size or mass through metabolic processes, reproduce and reproduce, and preserve or accumulate genetic information.

Materials that do not have these properties are considered " non- standard" organisms and viruses are one of them.

Viruses that do not have cytoplasm or organelles needed to synthesize energy. The process of "reproduction" of the virus actually relies on "borrowing" the host cells' organelles. In other words, the virus lies between the "live" and "not live" lines.

Klosneuviruses.

"To be or not to be"?

But where the virus comes from is still a controversial topic in biology. In terms of structure, the virus is extremely minimalist, usually with only one set of genetic information (in the form of DNA or RNA), protected by a protein class called casid.

In some cases, the virus has some other "stolen" material from the host cell. In terms of size, the virus is very small compared to bacteria or unicellular organisms so the virus is easy to invade biological cells and "hack" into the host's genetic apparatus, using exchange mechanisms. of the host to replicate itself.

With the above characteristics, there are two opposing views about the origin of the virus. Virus perspective is a " non-living" object that says they are just "lost" genetic materials but the "unintentional" gene structure allows for duplication so they still exist today.

Virus perspective is a "living" hypothesis that this is a product of evolution towards minimizing organelles, keeping only the genetic information set to "survive". If the latter is correct, the virus will be the fourth domain after three recognized organisms, eukaryotes, bacteria and archaea (archaea). Humans, animals, plants of eukaryotes.

3 areas of biology are being recognized.

However, these two points of view all have shortcomings that have not been overcome. The "not living" view does not explain why the virus has a protective casid. While other genetic materials do not have this characteristic, they are often destroyed when leaving the host cell.

In the opposite direction, the "living" view does not explain why the virus has such a simple structure. If they are truly a product of the organelles process, at least some viruses must have more than the genetic information set.

Giant viruses

By 2004, biologists had a shocking discovery when they found giant viruses (called girus).

Called giant because the amount of genetic information in them is so much that it can overcome even the simplest bacteria. Some have up to 2,500 genes, far more than the 11 genes of influenza virus.

The notable point in girus is that some genes allow the synthesis of proteins , which normal viruses do not have but the basic traits of all organisms. But it is so big, you still need to "hack in" a host cell to duplicate yourself.

Similar to viruses, biologists continue to ask questions - where does girus come from? This time, the "living" view seems to prevail with an explanation that girus is the rest of a living cell after removing organelles. Because if it is just a "lost" genetic material, 2,500 genes are "lost" together, which is an extremely difficult problem. Not to mention the factor that genes are present only on living cells, the "stray" is difficult to accept.

Where to find Klosneuviruses.

Fortunately, after more than a decade of "bluffing" , the "not living" view seems to have an answer to the question why girus has gathered so many genes.

Using the New Generation Genetic Sequence (NGS) method , a team of scientists mapped genes found in wastewater treatment plants located in Klosterneuburg (Austria). Thereby they classified a completely new girus strain and named them Klosneuviruses.

The "stealing" gene

Compared to other giraffes, Klosneuviruses are the group with the most protein synthesis genes. And when comparing the set of genetic information between different genotypes, the team found compelling evidence for protein synthesis genes that are a recent "stealing" product - not yes. Available from the beginning (coming from the organelle minimalism).

The picture illustrates the process of "stealing" the gene of girus.

The study, published last week in the journal Science, points out that in order to combat the "stealing" of viruses, some host cells have developed a mechanism to "hide" proteins when transmitting. Show intruders stranger. Without protein, the virus cannot replicate. But the confrontation between host and parasite is the confrontation between conflict and conflict.

In turn, some species have evolved towards "stealing" even the host gene, including genes that synthesize proteins. The result is that after countless generations, from viruses with only a few dozen genes, they have evolved to thousands of genes obtained from hosts. In other words, girus is not a minimalist version of real creatures.

But this study does not mean the "live" or "not live" virus debate has the answer. It is a fact that the number of species discovered by scientists is still just the tip of the iceberg. New species are still discovered every day. Some support this view. Others support the opposite view.

Perhaps it is only when people discover all species in the world that the definition of life is fully enlightened.