This Virus Shouldn't Exist (But it Does)

hidden in the microverse all around you there's a merciless war being fought by the true rulers

of this planet microorganisms amoeba protists bacteria archaea and fungi compete for resources

and space and then there are the strange horrors that are viruses hunting everyone else not even

alive they are the tiniest most abundant and deadliest beings on earth killing trillions every

day not interested in resources only in living things to take over also we thought turns out

there are giant viruses that blur the line between life and death and other viruses hunting them

considerably smaller than your cells or even bacteria viruses are nothing but a hull a tiny

bit of genetic material and a few proteins no metabolism no way to propel themselves no will

or ambition they float around aimlessly and hope to stumble upon a victim to infect and take over

viruses are so simple that we're not sure if they should count as living things or not

some scientists argue viruses are alive others think that the cells they infect are the actual

living viruses hybrid organisms called viral cells and the viral particles are more like seeds

or spores and many others think viruses are just dead material the origin of viruses is a mystery

because how can something that needs victims to make more of itself emerge in the first

place there are many ideas viruses may have been essential steps in the emergence of life or maybe

they started out as escaped dna from cells that became really good at making copies of themselves

maybe they are the descendants of truly lazy parasites that let others do all the work for

them the current thinking is that viruses probably emerged multiple times from different origins

but we simply don't know for sure yet whatever the truth is viruses are the most successful beings on

this planet there's an estimated 10 000 billion billion billion viruses on earth if we put them

all next to each other they would stretch for 100 million light years 500 milky way galaxies wide

very recently viruses became even weirder when scientists found a completely new type

giant viruses nicknamed gyrus not only did it break all sorts of records but questioned many

assumptions we had about their nature gyruses even come with their own parasites virophages

viruses that hunt other viruses which seemingly makes no sense at all and since we identified the

first one in 2003 it seems like these giants are everywhere we look in the oceans in water

towers in the guts of pigs and the mouths of humans and they're even weirder than we thought

gyruses look funny like hairy geometric forms or mini pickles much larger than

all viruses we knew before which explains how they could hide in plain sight for centuries

scientists saw them under their microscopes and just thought they had to be bacteria

it's like suddenly discovering there are elephant-sized ducks everywhere

most gyruses we've found so far hunt amoebi and other single-celled beings when they find a victim

they connect with it and use its natural processes to enter the cell like all viruses their goal is

to misappropriate the victim's infrastructure and procreate imagine a mouse crawling into your mouth

and using your guts and bones and fat tissue to build a mouse factory

the gyrus unloads its attack proteins and genetic material and rearranges the cell from the inside

its structural elements protein production machinery and large amounts of mitochondria

for energy are changed to become an actual factory called viroplasm some gyruses even

construct a membrane to shield them from the cell's antiviral defenses once finished the

viroplasm begins to assemble new gyruses using the victim up from the inside until it's filled up

finally the invader usually orders the cell to self-destruct and releases new gyruses to look

for new prey but what makes gyruses special is not their modus operandi or their size even

it's that they are much more complex than thought possible for a virus your cells have around 20

000 genes a typical bacterium has a few thousand genes the coronavirus has around 15 hiv or the flu

around 10. the number of genes alone is certainly not everything the tomato for example has 35

000 genes but generally we think of life as a complex system so below a certain complexity level

something may be closer to dead material rather than a living organism but gyruses

can have hundreds or even thousands of genes blurring the line between living and dead things

and it's not just the numbers that are special but also what these genes do we used to think of

viral genes as the simplest of instructions just enough to overcome the defense of their victims

and make new viruses but many gyrus genes are completely unique basically mystery genes

even more confusing a huge selection of their genes that are actually hallmarks of living

things genes that regulate nutrient intake energy production light harvesting replication or are

just necessary to keep cells alive some recent studies have even suggested that some gyruses

with very complex genomes may be able to maintain a basic level of metabolism on their own which if

true will shake up what we thought of viruses even more we still don't know anything for sure

but one idea about gyrus genes is that they might fundamentally alter the physiology and evolution

of their victims by integrating their own genomes and merging with them into chimeric organisms

or the other way around take some host genes with them and be changed themselves for billions of

years gyruses may have been existing alongside and infecting cells exerting an unseen influence

on the development of life not just as a parasite but jerking evolution in different directions by

mixing genes around in all directions which brings us to another unique thing about them virophages

the viruses hunting gyruses the concept itself is a bit mind-boggling how can a thing that might be

dead hunt another thing that might be dead too let's look at one of them the viruphage sputnik

is hunting a gyrus called mama virus that itself is hunting amoebi sputnik is a tiny

minimalistic virus that doesn't even have the genes and tools to replicate itself

what it does have is the ability to hijack the viroplasm factories of mama viruses so virophages

need their victim the gyrus to infect their victim an amoeba first and then they can parasitize it

a memovirus viroplasm infected by sputnik can only produce very few new gyruses and among these many

are deformed and broken unable to infect further cells instead it makes loads of new sputnik

viruphages other virophages are even more subtle when they infect a viroplasm they just integrate

their genetic code into the newly produced gyruses like sleeper agents the next time one of these

infiltrated gyruses successfully infects a cell it produces mostly viruphages instead of gyruses

gyruses are not completely defenseless though a few years ago the world was in

awe when scientists discovered crispr a bacterial defense system against viruses it turns out some

gyruses have a system that might be similar a sort of gyrus immune system against virophages

in turn virophages can also be used as an antigyrus defense mechanism by living cells

some protests have been found that integrated the genetic code of virophages into their genome and

kept it when the protists were infected by gyruses they used the code to create virophages themselves

to take over the gyrus factories in the end the protists would still be killed by the gyrus

infection but instead of releasing gyruses to kill its buddies it released virophages to hunt them

the amazing thing about everything we've told you in this video is that we're still very much at the

beginning it's not even been 20 years since the discovery of gyruses and virophages there is so

much going on in the microverse life is not an isolated event but a ping pong game of trillions

of organisms and viruses so when you feel down and like there's not that much new to discover think

of gyruses and all the other elephant-sized ducks all around us invisible until we look more closely

but how do you learn to look at the world like a scientist

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