Bacteria Eating Viruses, Phages. Bacteriophage

Bacteria Eating Virus. Phage

The struggle between living things is endless. Bacteria can "eat" our meat. Of course, there are also the little ones who feed on bacteria. That is phage, a virus that specifically "eats" bacteria.

What is virus?

Many people may not be able to distinguish the relationship between it and bacteria. There are many famous diseases, some are caused by bacteria, such as cholera or tuberculosis, and some are caused by viruses, such as influenza and rabies. 
Their pathogenic mechanism is completely different. Bacteria are like an army that invades the human kingdom. 
They have their own structures and organizations and can survive independently. Viruses, like drugs, can become contaminated. People do everything until exhaustion.

Therefore, the virus can be contaminated by the human kingdom bacteria, or it can be contaminated by the bacteria. 

Once the bacteria are contaminated by the phage, they will use all their resources to synthesize the proteins and DNA required by the phage, and eventually die.

In detail, bacteria are tiny cells that are smaller than most of our somatic cells, but they are indeed small cells that can complete the entire life cycle. 
Viruses are much smaller than bacteria. They are small boxes containing DNA proteins and oligosaccharides. 
If you zoom in, you can directly observe the atoms that make up it. Because they are too small, scientists have not been able to observe them through a microscope for a long time, so they thought it was a certain toxic substance. Now generally we define viruses as being between living and non-living, and they are also called "non-cellular structural living organisms".

Eating bacteria viruses

The first person to see the phage will be surprised with its rather sci-fi style. They look like tiny robots, imitating spider robots. Especially their polyhedral shape also reveals a cyberpunk style. , More and more like an artificial object.

So why is it this shape? What is interesting about phage?

The entire bacterio phage family is very large, ancient and rich, and they have appeared on the earth with bacteria almost three billion years ago. The number of bacteriophages is very, very large, and they are more than all other life on earth (including all bacteria) combined. May be more than 10 ^ 31 (10,000 .. 000, a total of 31 zeros). 

The earth’s environment with the most phage is seawater, and more than 70% of the bacteria in the sea may have infected the phage.

International Council of Taxonomic Classification (ICTV)'s Classification

The International Council of Taxonomic Classification (ICTV) has classified phages based on morphology and nucleic acid. There are 19 families of phages, of which only two families are based on RNA and five families are enveloped viruses.

Of the phage family with DNA genomes, only two are DNA single-stranded structures. Eight of the viral families with double-stranded DNA genomes are circular genomes and nine are linear genomes. Nine families are infected with bacteria only, nine families are infected with archaea, and one family is infected with both bacteria and archaea.

Phage Appears as Robot

The most common type of phage that looks like a small robot is called T2 phage, which is targeted at E. coli and is a powerful phage. The so-called fierce refers to that it will certainly kill the invading bacteria. In contrast, there are some milder phages. Their relationship with bacteria is like humans and roundworms, and they can be parasitic in bacteria for a long time.

Mildness is an inevitable product of natural co-evolution, because too severe lethality sometimes cuts off the source of infection and prevents it from continuing to spread, so the choice to maximize benefits is better "forever", so even the phage infection So high, bacteria can still survive

Two Main Structures-DNA and shell

Regardless of its complex shape, there are actually only two main structures-DNA and shell. DNA contains a wealth of information, mainly used to synthesize shell information, including the head, neck ring, tail sheath, tail tube, substrate, spikes and tail filaments.

Guide to invasive bacteria

So how do they infect bacteria? 

First of all, we have to understand one thing: the virus itself has no power. It only spreads in the solution environment, so if you want to catch the bacteria, you must have a corresponding structure. 

The six lovely calves are used for this purpose. 
Their molecules are structurally attractive to those of the outer capsule of the bacteria, so when the phage randomly contacts the surface of the bacteria under the Brownian motion of the water molecules, the tail will stick to the bacteria instead of the head.

At the tail we can see a structure called a spike, which also peels off the protective layer of the bacteria at the molecular level. 
This is different from the macroscopic puncture, which is separated by the attractive force of the molecule and then closed together. DNA in the head also enters the bacteria due to thermodynamic movement.

We know that the genetic material of bacteria is DNA, and its working principle is to convert its own information into proteins through the ribosome in an environment rich in various molecular materials inside the cell.

In the same way, after the phage DNA enters the bacteria, its DNA will also use existing raw materials and ribosomes to synthesize proteins. These are the various structures that make up the phage shell.

Of course, these DNAs not only "steal" the bacteria's raw materials to synthesize their own shells, but also replicate themselves. After a certain period of time, the bacteria will be filled with phage synthesis.

Then is the last and most interesting step to form the virus-assembly. We may be surprised by its complex structure. In fact, these are also due to the molecular structure. They collide randomly with the thermodynamic Brownian motion in the bacterial body fluid, and the appropriate structures will stick together by themselves, such as on the substrate. 

6 molecular protrusions

There are six molecular protrusions. This position can be combined with one end of the tail wire, and other structures are not possible. In this way, the six lower legs are successfully combined in a collision and become delicate and magical phages.

Delicate relationship

Then the outer shell of the bacteria that has been sucked up by the phage will collapse, and the internal phage will rush out, come to the environment, and continue to infect other bacteria. 

The speed of replication is the key to determining whether the phage is virulent.

If the replication is too fast, the bacteria will explode. If the replication is slow, it is a parasitic relationship.

Therefore, the relationship between bacteria and bacteriophage is also very delicate, just as the slave owner would not have a slave to be exploited if he did not create a clean environment for the slaves and treat them. (Southern Black Slave Plantation in the United States). Phages sometimes even protect bacteria.

For example, the Soviet Union and France tried to use phages to treat bacterial infections, but scientists later found that phages not only became less effective because of their reduced strength, they even helped bacteria build a protective layer that other drugs could not use take effect.

Why is there a punk head structure in Bacterio Phage?

So why does the bacterio phage have a very sci-fi head? In fact, it is also very easy to understand. First of all, molecules can form geometric structures spontaneously, such as hexagons of ice crystals, because the angle between two hydrogens of water molecules is 120 degrees. 

The head of the bacterio phage is a regular icosahedron with 12 vertices, 30 sides, and 20 equilateral triangles, each angle being 60 degrees, which is compatible with the atomic structure of the molecule.

Using this structure is also the most economical and reasonable way to form a closed space at the molecular level. Not only phages, but also a lot of viruses also use this structure, such as the adenovirus in the figure below. 

Similarly, the spiral structure forming the tubular structure is also a natural product of the special angle of the molecular structure. Although these structures are exquisite, they are not incomprehensible, and they have nothing to do with aliens and magic creations.

Conclusion

This is the boundary of life we ​​now know, one of the viruses that have been lingering on the boundary between life and non-life: a brief knowledge of phages, the applications of phages will be very extensive, and biologists are working hard to study them. 

As stated in the title, phages may be the reference for nanorobots, and our research on phages may have important guiding significance for the future manufacturing of organic nanorobots.

Author's Bio

Dr. Shawna Reason

Name: Shawna Reason

Education: MBBS, MD

Occupation: Medical Doctor / Virologist 

Specialization: Medical Science, Micro Biology / Virology, Natural Treatment

Experience: 15 Years as a Medical Practitioner

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