The idea of a deadly artificial bacteria taking over the human body might sound like something from the next season of The Last of Us.
But a Nobel Prize-winning biologist has now warned that it could become a reality, amid rising interest in deadly ‘mirror bacteria’.
Mirror bacteria are a type of fully synthetic life in which all the biological molecules are replaced with ‘mirrored’ alternatives.
Last week, a group of 38 leading scientists from around the globe issued an urgent warning calling for a halt on research which could create these lethal lifeforms.
Professor Gregory Winter, a molecular biologist from the University of Cambridge, who won the Nobel Prize in 2018 for his work on the evolution of antibodies, has now revealed to MailOnline exactly how these bacteria could take over the human body.
‘If they found their way into the blood, colonies of mirror bacteria could, for example, block up blood vessels, leading to failure of circulation and strokes,’ he warned.
‘Or they could colonise the sites of wounds, leading to wounds that don’t heal, helping infection by existing pathogenic bacteria.’
To make matters worse, Professor Winter warns that it would likely be ‘impossible’ to create a vaccine against these lethal infections.
It might sound like something out of The Last of Us (pictured) but scientists now warn that a deadly ‘mirror bacteria’ could take over the human body
A Nobel Prize-winning scientist has revealed how deadly ‘mirror bacteria’, a form of synthetic life made of mirrored biological molecules, could create deadly infections that our bodies would be unable to defend against (stock image)
In all life on Earth, there are a number of molecules which have a property of handedness or ‘chirality’.
Just like your left hand is a mirror of your right, for each of these chiral molecules there exists a left and right-handed version.
These chiral molecules are a key part of basic cell function including DNA’s right-handed spiral and the left-handed amino acids which make up every protein in our bodies.
However, since these molecules’ mirror versions are otherwise identical, there is no reason that life shouldn’t have evolved to have the opposite chirality.
This means that it is possible to build an artificial form of life in which every chiral molecule is replaced with its mirror version, creating a fully functioning mirror cell.
Even though the technology to do this is more than a decade away at the earliest, a group of scientists have recently begun to raise the alarm over the potentially devastating consequences of mirror life.
In a 300-page technical report, these researchers warned that there would be very little preventing mirror bacteria escaping from the lab and becoming established in the wild.
Professor Winter says: ‘Bacteria can grow on nutrients that are non-chiral, converting these into chiral molecules, for example left-handed amino acids.
Professor Gregory Winter (pictured), a Nobel Prize-winning molecular biologist from the University of Cambridge, told MailOnline that infections of mirror bacteria could block blood vessels leading to strokes, circulation failure, or wounds that are unable to heal
‘The same would be true for mirror bacteria except they would convert the non-chiral molecules into right-handed amino acids.
‘Infecting mirror bacteria could therefore grow in living organisms using the non-chiral molecules as a source of nutrients.’
That would allow mirror bacteria to multiply within the body and create physical blockages.
While they can’t interact with our bodies chemically, the bacterial colonies would eventually grow to the point that they clog up our blood vessels – leading to fatal consequences.
The reason this is so dangerous is that life on Earth has evolved defence mechanisms based on chiral molecules like right-handed DNA and left-handed proteins.
This means that the immune systems of every organism on the planet would not be able to destroy or even detect an infection of mirror bacteria.
‘For example, human white cells in the blood have evolved to recognise and digest invading bacteria, but the “left-handed” enzymes involved would struggle to digest “right-handed” proteins of the mirror bacteria,’ says Professor Winter.
‘For similar reasons, it would be difficult or impossible to create effective vaccines against mirror bacteria.’
In a recent paper published in Science, 38 leading scientists called for a pause on research into mirror life. This is because the mirrored proteins would make these bacteria invisible to our bodies’ immune system (stock image)
Professor Winter says that, in time, it might be possible to create suitable antibiotics to deal with mirror bacteria or create bacterial viruses to attack and kill the mirror bacteria.
However, he says that there is ‘no guarantee that we would have the time’ to develop these defences before serious damage is already done.
If a mirror bacteria escaped from a lab into a populated area these unique characteristics mean it could lead to devastating consequences.
Professor Winter says: ‘At the beginning, it might spread slowly as it wouldn’t have specialised mechanisms to infect humans, but it could soon start to evolve and become more infectious.
‘More worrying, it could infect other living organisms, including plants and animals, and be impossible to eradicate from the delicate ecosystem that supports us.
‘Climate change would be least of our problems if mirror bacteria escaped into the environment.’
Yet an outbreak of mirror bacteria could be even more disasterous than the pathogens imagined by apocolyptic films and television like 12 Monkeys and Contagion.
In those pieces of science-fiction the spreading infection only attacks people, leaving the rest of nature to flourish.
An outbreak of a mirror bacteria could be even more disasterous than the diseases imagined by apocolyptic films like Contagion (pictured) since the bacteria would affect all life on Earth, not just humans
However, mirror bacteria wouldn’t need to specialise to infect any particular species and could spread through any organism on Earth.
Since mirror bacteria don’t interact with the immune systems of their hosts, they would be able to infects plants and animals just as easily as humans.
That means mirror bacteria could infect every living plant, potentially devastating food crops around the world.
Dr Jonathan Jones, a co-author on the paper and plant disease expert from the Sainsbury Laboratory, told MailOnline: ‘Plant disease is something that is quite rare actually, most pathogens can’t grow on most plants.
‘But if this played out, you might end up with a bacterium that could grow on all plants; so it’s not just the crop plants we need to worry about, it’s the whole ecosystem.’
The good news is that mirror life is currently no more than a theoretical risk.
Currently, researchers have made some progress in manufacturing mirror proteins and the field of artificial cell construction but both of these fields are in their relative infancy and would need decades of work to get to the point of making mirror life.
Dr Andreas Plückthun, an expert in protein engineering from the University of Zurich who has worked on the creation of mirror proteins, told MailOnline that creating mirror life would take ‘the concerted effort of a thousand people for 20 years’.
Unlike most of the world’s deadliest pathogens (illustrated) there would be no way to defend against mirror bacteria. Mirror bacteria would also be able to infect any organism regardless of species, potentially leading to massive ecological damage and a devastating pandemic
‘This is not something that’s inconceivable but it’s not something a terrorist could do in a basement,’ Dr Plückthun says.
The cost of generating a mirror organism would also be astronomical with costs extending into the tens of millions of dollars to create even small stretches of DNA.
And, while mirror proteins themselves could have potentially life-saving applications in cancer treatment or other therapies, there is almost zero benefit to making a mirror bacterium.
Dr Plückthun says: ‘One has to realise that the effort to do this is so huge and that the time needed would be so long that this is a super remote possibility that surely doesn’t worry me.’
