Can viruses be toxic?

Bacteria can produce toxins like endotoxins and exotoxins. In diseases like cholera or tetanus they can harm infected people due to these toxins. Now, although viruses are much smaller and are dependent on the host cell for their production, are there DNA sequences in viruses which can produce similar toxins, or are viruses made of something that is toxic?

If not, can viruses be seen as causing an allergic reaction because like common allergies they don't harm directly, only our immune system generates the problems?

In general, DNA that encodes toxins can be incorporated in a viral genome and thus it can be expressed in the infected host inducing toxicity. Here an example:

Also, viruses can trigger allergic reactions ( or promote them (

Finally, there are some reports about viruses causing "with symptoms that mimic allergies" (

In addition to @alec_djinn's answer, viruses can also indirectly be toxic by causing lysis in cells that themselves have toxic components. The presence of bacterial endotoxins in poorly filtered solutions of early attempts at phage therapy is probably the canonical example of this.

In theory, there's no reason why a virus couldn't encode bacterial toxins. In practice, that doesn't happen much because viruses have no incentive to sabotage their host cells in that manner - there's largely no fitness advantage, all it would do is make the viral genome larger and shut down the host cell preventing further replication.

Even if a virus specifically wanted to shut down its host cells, it's more efficient to spawn large numbers of copies of itself and exhaust the host cell's resources.

in short:

virus produces toxins in host cell -> host cell dies -> no replication opportunity and virus gets trapped in the cell

virus produces large numbers of copies of itself -> host cell runs out of resources and dies -> numerous replications and avoid getting trapped

Yes viruses can import toxin encoding genes, at least in humans and in plants.

With Ebola a protein called Delta-Peptide is released in large amounts by the virus genome, and it attaches to cell walls and makes them more permeable. it does this to the cell wall, and some researches have described it as ebola toxin.

Toxin from a maize virus:

Conversely, plants generally use alkaloids as toxins. Alkaloids are a large family of N containing organic molecules, for example those found in Datura, Angel of Death mushroom, Cyanide, etc. and I found no evidence that viruses make us produce alkaloids. Scientists research on the anti-viral abilities of some alkaloids.

Tonins in venoms are more often protein based… Tangentially to your question, here's a page on the diversity of venom toxins for background.

Viruses Can Be Delicious as Well as Deadly

Now that we&rsquove been held hostage by a virus for seven months that feel like seven years, many of us could use some good old-fashioned retribution. Well, it turns out there is a satisfying place where the viruses are the ones that have to worry about social distancing, and that place is the ocean.

In seawater, viruses massively outnumber cellular life. There are an estimated 10 30 virions there. Their victims are usually bacteria or other microbes. Every second this viral swarm infects 10 23 such creatures, killing 20 percent of the ocean&rsquos microbial biomass each day (ocean microbes reproduce so quickly and often that they maintain an equilibrium nevertheless). It&rsquos hard to imagine such a horde could escape the culinary attentions of everything in the sea.

Viruses also have some features that make them potentially appealing entrees. Compared to cellular life forms, they are rich in phosphorous and nitrogen, making them nutritious as well as abundant little nibbles.

Yet it&rsquos long been thought marine viruses serve only one function: killing. Like the sludgy recycling pit in Waterworld, their role has been seen by ecologists as &ldquoviral shunt,&rdquo a fancy way of saying viruses are good at converting living creatures into drifting bits of the &ldquopool of dissolved organic matter.&rdquo

But a recent report in the journal Frontiers in Microbiology suggests the reverse can also occur: viruses are microbe chow.

Until now, I had never considered viruses as a potential foodstuff, and apparently, few scientists had either. Although at least five studies had suggested that microbes may prey on viruses, until this most recent report, no one had followed up to discover just how widespread or important the process actually is.

A team of American and Spanish scientists finally decided to examine whether grim reaping was truly viruses&rsquo only function, and to what extent any alternative was the case, by screening the cells of marine microbes for associated viral genes.

The microbes in question were not bacteria or archaea, the simplest cells. Rather, they were protists: tiny life forms that&mdashsimilar to their much larger cousins known as plants and animals&mdashhave complicated cellular furniture called organelles that house DNA, produce energy and do all sorts of other jobs.

This team analyzed a variety of protists from water samples from the Gulf of Maine and the Mediterranean Sea. Viral genes were detected alongside 51 percent of protist cells from the gulf and 35 percent from the sea.

Two groups, the Picozoa and the Choanozoa, were always found associated with viruses, and contained many more viral sequences per cell than other groups.

Though obscure to humans, choanozoans and picozoans are important and abundant in the ocean. Picozoa are the size of bacteria, minuscule even for protists. These creatures, in spite of being prolific enough to make up half of the biomass in nutrient-poor coastal waters, were completely new to science as of 2007.

Choanozoa, also called choanoflagellates, are the closest living relatives of animals and sport a jaunty collar and tail with which they both move and capture prey. They too are tiny, yet choanozoa are estimated to filter 10&ndash25 percent of coastal surface water each day, a staggering sum.

In this study, choanozoans averaged an incredible 28 viral sequences per cell picozoans 5.7. However, as only 22 out of 1,698 protist genomes detected belonged to these two groups, these results are certainly suggestive but by no means definitive.

What could explain the presence of these viruses in the many protists studied? One might expect that if they were parasites rather than supper, we would observe a wide variety of sequences for targeting many potential hosts. If they were food, on the other hand, we might expect just a few sequences as grazers and predators indiscriminately gobble the most abundant viruses.

In this study, most of the viruses detected were nearly identical, few were specific to particular protists, and many infect only bacteria: bacteriophages and gokushoviruses. Also detected was a new and somewhat mysterious group called CRESS DNA viruses, whose hosts are diverse. These too had nearly identical sequences.

To assume near-identical viruses were infecting all the cells studied in this report would imply that some viruses are capable of infecting organisms from different phyla, the taxonomic rank just below kingdom, the authors say. No known virus can do this.

What are some other alternatives? It&rsquos possible the viruses inserted themselves into the protists&rsquo genomes, a feat that the chickenpox virus is famous for (it can reemerge years after the initial infection as shingles). Many other viruses can end up as permanent residents of their host&rsquos genome, which from the viral perspective is ideal as it confers immortality without the continual bother of trying to find a new host. But the near-identical sequences detected once again argue against this, because random mutations in viruses isolated within particular genomes should result in a variety of sequences.

Perhaps the viruses ended up in the protists because they were eating bacteria that happened to be infected by viruses. But many of the protists contained viral genes without any bacterial genes. It&rsquos also possible the viruses were randomly assorted into the sample wells along with the protists. But the fact that some protist lineages were found with many more viruses than others seems to argue against that.

Perhaps there&rsquos something about the surfaces of Picozoans and Choanozoans that makes them especially sticky to viruses. But the way these protists eat makes viral ingestion more likely, the authors argue. They are suspension feeders: they eat whatever they can swallow that is unlucky enough to bump into them. Since previous studies have shown choanozoans and picozoans are certainly capable of consuming viruses, their universal presence and abundance suggests that is exactly what the protists are doing.

Choanozoans and Picozoans may not be unique in their eating habits, either. Several other protist groups in this study also contained more viral sequences than would be expected by chance, but because these other protists feed in many ways, the authors refrained from making inferences about the viruses&rsquo presence.

In retrospect, it&rsquos not entirely surprising that massively abundant, defenseless, drifting bonbons of protein and nucleic acid would be scarfed up by something. A paper also published this year in Scientific Reports even showed that marine sponges were extremely efficient at removing viruses from seawater and concluded it was possible they too are eating viruses.

Protists &hellip sponges &hellip how many more creatures out there have food pyramids that include viruses? Why didn&rsquot we know this? And how can we get in on the action?

The idea of viruses as food for anything is a bit mind-warping, but it&rsquos also a rich source of schadenfreude at a moment where humans could really, really use some. While we are at the undisputed mercy of one virus, it&rsquos satisfying to think about legions of others meeting their ends in the gullet of a living, breathing cell.

Friendly Viruses Protect Us Against Bacteria

Bacteria can be friends and foes—causing infection and disease, but also helping us slim down and even combating acne. Now, a new study reveals that viruses have a dual nature as well. For the first time, researchers have shown that they can help our bodies fight off invading microbes.

"This is a very important story," says Marilyn Roossinck, a viral ecologist at Pennsylvania State University, University Park, who was not involved in the work. "We don't have all that many examples of beneficial viruses."

One of our most important lines of defense against bacterial invaders is mucus. The slimy substance coats the inside of the mouth, nose, eyelids, and digestive tract, to name just a few places, creating a barrier to the outside world.

"Mucus is actually a really cool and complex substance," says Jeremy Barr, a microbiologist at San Diego State University in California and lead author of the new study. Its gel-like consistency is thanks to mucins, large, bottle brush-shaped molecules made of a protein backbone surrounded by strings of sugars. In between the mucins is a soup of nutrients and chemicals adapted to keep germs close, but not too close. Microbes such as bacteria live near the surface of the layer, whereas the mucus at the bottom, near the cells that produced it, is almost sterile.

Mucus is also home to phages, viruses that infect and kill bacteria. They can be found wherever bacteria reside, but Barr and his colleagues noticed that there were even more phages in mucus than in mucus-free areas just millimeters away. The saliva surrounding human gums, for example, had about five phages to every bacterial cell, while the ratio at the mucosal surface of the gum itself was closer to 40 to 1. "That spurred the question," Barr says. "What are these phages doing? Are they protecting the host?"

To find out, Barr and his colleagues grew human lung tissue in the lab. Lungs are one of the body surfaces that is protected by mucus, but the researchers also had a version of the lung cells where the ability to make mucus had been knocked out. When incubated overnight with the bacterium Escherichia coli, about half the cells in each culture died the mucus made no difference to their survival. But when the researchers added a phage that targets E. coli to the cultures, survival rates skyrocketed for the mucus-producing cells. This disparity shows that phages can kill harmful bacteria, Barr says, but it's not clear whether they help or hurt beneficial bacteria that may depend on which types of phages are present.

In a related series of experiments, the team found that the phages are studded with antibodylike molecules that grab onto the sugar chains in mucins. This keeps the phages in the mucus, where they have access to bacteria, and suggests that the viruses and the mucus-producing tissue have adapted to be compatible with each other, the team reports online today in the Proceedings of the National Academy of Sciences.

Mucus-covered surfaces aren't unique to our insides the slime can be found throughout the animal kingdom. It protects the whole bodies of fish, worms, and corals, for example. Protective phages seem to be equally widespread: Barr and his colleagues found dense populations of phages in every species they sampled. "It's a novel immune system that we think is applicable to all mucosal surfaces, and it's one of the first examples of a direct symbiosis between phages and an animal host," Barr says.

In this study, the researchers chose the phage and the bacterium, but it's possible that the animal host selects specific phages to control specific types of bacteria, such as by outfitting mucins with particular sugars that those phages recognize. The next step, Barr says, is to explore how this symbiosis works in real-life mucosal surfaces of all types, where many different types of phages and bacteria are interacting.

"This is a novel take on the whole microbiome-host relationship," adds Michael McGuckin, a mucosal biologist from Mater Research, a medical research institute in South Brisbane, Australia, who was not involved in the work. The finding, he says, could provide insights into conditions such as inflammatory bowel disease (IBD). We all have an ecosystem of hundreds of bacterial species in our gut, but patients with IBD have a disrupted ecosystem with different dominant species. These diseases, which include Crohn's disease and ulcerative colitis, also involve a breakdown in the mucus lining of the gut, he says, and this new study suggests that a failure in phage-based immunity might be the link between those symptoms.

McGuckin is intrigued by the idea that phages may help select the types of bacteria that live inside us. "There's tons of questions around just how this whole system might control microbial populations in the gut, which have increasingly been shown to be important in obesity and diabetes, and all sorts of human conditions."

It may also be possible to design a mucus-compatible phage that could fight infection or alter the body's microbial balance, although that possibility is still very distant. This work, Barr says, "forces us to reevaluate the role of phages. Hopefully this will get people thinking about what they do and how we can use them to help us and combat disease."

How viruses destroy bacteria

Viruses are well known for attacking humans and animals, but some viruses instead attack bacteria. Texas A&M University researchers are exploring how hungry viruses, armed with transformer-like weapons, attack bacteria, which may aid in the treatment of bacterial infections.

The Texas A&M researchers' work is published in the journal Nature Structural & Molecular Biology.

The attackers are called phages, or bacteriophages, meaning eaters of bacteria.

The word bacteriophage is derived from the Greek "phagein," meaning eater of bacteria.

"The phages first attach to the bacteria and then inject their DNA," says Sun Qingan, coauthor of the article and a doctoral student at Texas A&M. "Then they reproduce inside the cell cytoplasm."

After more than 100 phage particles have been assembled, the next step is to be released from the bacterial host, so that the progeny virions can find other hosts and repeat the reproduction cycle, Sun adds.

Besides the cell membrane, the phages have another obstacle on their way out -- a hard shell called cell wall that protects the bacteria. Only by destroying the cell wall can the phages release their offspring.

But, don't worry. The phages have a secret weapon -- an enzyme that can destroy the wall from inside, thus called endolysin.

"One of the special examples, R21, remains inactive when it is first synthesized and attached to the membrane as demonstrated in our paper," Sun explains. "But when the enzyme leaves the membrane, it restructures just like a transformer and gains the power to destroy the cell wall."

The trigger controlling the transformation process is a segment of the enzyme call the SAR domain, according to the Texas A&M team.

"The SAR domain is like the commander -- it tells the enzyme when to begin restructuring and destroying the cell wall," he says. "This finding enables us to better understand the release process and provides us with a possible target when we want to control the destruction of bacteria cell walls or prohibit this action in some infectious diseases."

Some research has been conducted to explore the possibility of using phages to kill bacteria and thus treating bacterial infections.

Sun and colleagues' finding unveils one secret of the phages and may be useful in phage therapy and other applications.

Story Source:

Materials provided by Texas A&M University. Note: Content may be edited for style and length.

Harmful viruses and even friendly bacteria may cause premature ageing

Getting old is an inescapable fact of life, like wet British summers. But age may not be entirely due to processes in our body cells. Instead, our bodies may age in part because of the actions of microorganisms like bacteria, which interfere with our biology.

“Are we older than we could be due to interactions with other species?” asks Eric Bapteste at the National Museum of Natural History in Paris, &hellip

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6 Norovirus

Virologists have become especially interested in noroviruses. These particular micro life-forms are well known for their ability to cause epidemics of diarrhea on cruise ships. They are also infamous for their ability to ravage laboratory mice colonies with the disease.

But as it turns out, some strains of the virus have proven useful&mdashespecially for their role in helping to &ldquonormalize&rdquo mice that have grown in sterile environments. These mice don&rsquot make enough T cells, which hurts their gut bacteria and immune response.

To fix the problem, researchers have shown that giving bacteria to the mice can help to rebalance their immune cells, but adding a norovirus to the mix can actually solve the same problem. Researchers also found that some norovirus strains helped lessen the effects of pathogens that usually cause weight loss, diarrhea, and other related symptoms in mice.

This makes for an exciting discovery as researchers unveil new ways to use viruses for good. Giving strains of the norovirus to humans to treat other diseases would be seen as highly controversial, but much evidence says that it could actually help. [5]

Harmful Microbes

Students explore how microbes can be harmful to specific body systems as they engage in a jigsaw reading activity that builds on what they learned in the Helpful Microbes activity. Students also analyze the design of three public service announcements.

This lists the logos of programs or partners of NG Education which have provided or contributed the content on this page. In collaboration with

1. Students learn about harmful microbes from a PSA about foodborne disease that presents a case study about Escherichia coli, known as E. coli.

  • Prepare students to watch the PSA by building background knowledge about E. coli. Show a picture of E. coli (See "Scanning Electron Microscope (SEM)" image in the slideshow at the top of this page) and ask what students know or can predict about this particular microbe.
  • Build on students’ prior knowledge as you provide the following information about E. coli: Scientific name: Escherichia coli
      • Scientific classification: Bacteria one species that is further broken down into specific strains.
      • Where it is found: Normally lives in the intestines of humans and animals and are harmless.
      • Impacts on humans: Certain strains of it can make people sick.
      • How transmitted: By consuming water and food contaminated by infected feces.
        • What is the purpose of this PSA?
        • Who is the intended audience?
        • What is its call to action?
          • What is the PSA’s purpose, audience, and call to action? (Possible responses: The purpose is awareness and responsibility for prevention intended audience is consumers and the call to action is that understanding various factors that can lead to foodborne illness (farm, processing, transportation, vendors, consumers) helps us protect ourselves and communities.)  
          • Based on what you know about bacteria and other microbes, which parts of our food system could help transmit E. coli? (Possible responses: Warm temperatures during transportation and unhygienic conditions at farms and vendors provide optimal environments for bacteria to survive and reproduce.)
          • During the outbreak discussed in the PSA, lettuce, tomatoes, and sprouts were all considered possible sources. Why do you think fresh vegetables could be carriers for E. coli? (Possible responses: Vegetables that have been exposed to contaminated water or another source of E. coli need to be washed thoroughly or cooked to eradicate the bacteria this sometimes does not happen with vegetables that are consumed raw.)

          2. Students learn about specific types of microbes that have harmful impacts on the human body through a jigsaw.

          Expert groups collaborate to learn about specific types of microbes that can be harmful.

          • Prompt students to return to their Microbes: Our Best Frenemies handout, which students will continue to use throughout this lesson.
          • Use the same jigsaw structure and groupings that you used in the Helpful Microbes activity, follow the steps below to have students engage with and share about different parts of the Infectious Agents infographic.
          • Assign each expert group to one type of the following infectious agents. Depending on the number of groups, it is likely multiple groups will be assigned to the same agent.
              • Bacteria
              • Viruses

              Jigsaw groups share what they have learned about harmful microbes.

              • Reorganize students into their jigsaw groups. Each group member is now an expert on a different type of microbe and should share out to the rest of the group. Group members should take notes on the remaining microbes listed in Part B of the handout.

              3. Introduce the immune system and how it helps protect the body from infection or disease caused by microbes.

              • Elicit students’ initial ideas about the immune system and how it works.
              • Then show the Innate Immune System video to introduce the body’s first line of defense against microbes that cause infection or disease.
              • Ask: How does the immune system help the body to protect against the type of microbe that you became an expert in?
              • Then show the Adaptive Immune System video to introduce the body’s second line of defense. This is relevant for all pathogens, but will especially help students whose focal microbe was a virus.

              4. Analyze two sample PSAs about microbes’ harmful impacts to help prepare students for their project work.  

              • Remind students about the project they will undertake in this unit: Students collaborate in small groups to create a public service announcement (PSA) with an online animation app (teacher’s choice) to introduce a particular microbe to their community. Their PSA will include an evidence-based argument regarding the value of eradication of the microbe, based on its various impacts on the systems of the human body.
              • Explain that they will watch and analyze two more sample PSAs.
              • Direct students to the PSA Design Analyzer. They should use the third and fourth design
              • squares to analyze the following design elements:
                  • Visuals / animation
                  • Text
                  • Information
                  • Call to action

                  Informal Assessment

                  The Microbes: Our Best Frenemies handout can be used to assess students&rsquo individual understanding about how microbes harm the human body. Additionally, during the multiple discussions throughout the activity, assess the accuracy of connections that students make between systems of the body and harmful microbes.

                  Extending the Learning

                  Consider framing the ecological relationships discussed in this activity through the lens of symbiosis, emphasizing that the majority of the relationships between microbes and humans are neutral.

                  US military wants to know what synthetic-biology weapons could look like

                  A study ordered by the US Department of Defense has concluded that new genetic-engineering tools are expanding the range of malicious uses of biology and decreasing the amount of time needed to carry them out.

                  The new tools aren’t in themselves a danger and are widely employed to create disease-resistant plants and new types of medicine. However, rapid progress by companies and university labs raises the specter of “synthetic-biology-enabled weapons,” according to the 221-page report.

                  The report, issued by the National Academies of Sciences, is among the first to try to rank national security threats made possible by recent advances in gene engineering such as the gene-editing technology CRISPR.

                  “Synthetic biology does expand the risk. That is not a good-news story,” says Gigi Gronvall, a public health researcher at Johns Hopkins and one of the report’s 13 authors. “This report provides a framework to systematically evaluate the threat of misuse.”

                  Experts are divided on the perils posed by synthetic biology, a term used to describe a wide set of techniques for speeding genetic engineering. In 2016, the US intelligence community placed gene editing on its list of potential weapons of mass destruction.

                  “Many different groups have written and spoken about the topic, with a wide spread of opinion,” says D. Christian Hassell, deputy assistant secretary of defense for chemical and biological defense, who commissioned the report in order to obtain a “consensus opinion from among the top leaders and thinkers” in the field.

                  Hassell says the military’s current view is that “synbio is not a major threat issue at the moment” but bears preparing for, in part because defenses like vaccines can take years to develop.

                  The current report attempted to weigh potential threats by considering factors such as the technical barriers to implementation, the scope of casualties, and the chance of detecting an attack. It found that while “some malicious applications of synthetic biology may not seem plausible right now, they could become achievable with future advances.”

                  Among the risks the authors termed of “high concern” is the possibility that terrorists or a nation-state could re-create a virus such as smallpox. That is a present danger because a technology for synthesizing a virus from its DNA instructions has previously been demonstrated.

                  The evaluation process shed light on some risks the authors called unexpected. In one scenario, the report imagined how ordinary human gut bacteria could be engineered to manufacture a toxin, an idea ranked as highly worrisome in part because such an attack, like a computer virus, could be difficult to uncover or attribute to its source.

                  Among the weapons imagined, several involved CRISPR, a versatile gene-editing tool invented only six years ago, which the report said could be introduced into a virus to cut human DNA and cause cancer. If scientists can alter animals to create disease, “it follows that [the] genomes of human beings could be similarly modified,” according to the report.

                  In its analysis, the committee downgraded other threats. Attempts to construct entirely novel man-made viruses, for instance would be hobbled by scientific unknowns, at least for now.

                  The US military, which asked for the study, is already among the largest funders of synthetic biology. Although its research is defensive in nature, technical reports such as this one, which imagine future weaponry, could generate anxiety in other nations, says Filippa Lentzos, a senior research fellow in biosecurity at King’s College London.

                  “You don’t want to start a new bioweapons race. The field needs to ask itself who is driving the agenda, and how does this look from the outside,” she says. “Synthetic biology has a problem, which is that much of its funding comes from the military.”

                  Historically, the US and other countries have worried most about specific germs such as smallpox, including them on a list of “select agents” whose possession is tightly controlled.

                  As the biotech tool box grows, however, the list-based approach to security is no longer seen as sufficient.

                  According to the report, the US must now also track “enabling developments” including methods, widely pursued by industry, to synthesize DNA strands and develop so-called “chassis” organisms designed to accept genetic payloads.

                  “The US government should pay close attention to this rapidly progressing field, just as it did to advances in chemistry and physics during the Cold War era,” says Michael Imperiale, a microbiologist at the University of Michigan and chair of the committee behind the publicly available report, titled Biodefense in the Age of Synthetic Biology.

                  This new cyberattack can dupe DNA scientists into creating dangerous viruses and toxins

                  The research highlights the potential dangers of new 'biohacking' techniques.

                  By Charlie Osborne for Zero Day | November 30, 2020 -- 10:00 GMT (02:00 PST) | Topic: Security

                  A new form of cyberattack has been developed which highlights the potential future ramifications of digital assaults against the biological research sector.


                  On Monday, academics from the Ben-Gurion University of the Negev described how "unwitting" biologists and scientists could become victims of cyberattacks designed to take biological warfare to another level.

                  At a time where scientists worldwide are pushing ahead with the development of potential vaccines to combat the COVID-19 pandemic, Ben-Gurion's team says that it is no longer the case that a threat actor needs physical access to a "dangerous" substance to produce or deliver it -- instead, scientists could be duped into producing toxins or synthetic viruses on their behalf through targeted cyberattacks.

                  The research, "Cyberbiosecurity: Remote DNA Injection Threat in Synthetic Biology," has been recently published in the academic journal Nature Biotechnology.

                  The attack documents how malware, used to infiltrate a biologist's computer, could replace sub-strings in DNA sequencing. Specifically, weaknesses in the Screening Framework Guidance for Providers of Synthetic Double-Stranded DNA and Harmonized Screening Protocol v2.0 systems "enable protocols to be circumvented using a generic obfuscation procedure."

                  When DNA orders are made to synthetic gene providers, US Department of Health and Human Services (HHS) guidance requires screening protocols to be in place to scan for potentially harmful DNA.

                  However, it was possible for the team to circumvent these protocols through obfuscation, in which 16 out of 50 obfuscated DNA samples were not detected against 'best match' DNA screening.

                  Software used to design and manage synthetic DNA projects may also be susceptible to man in-the-browser attacks that can be used to inject arbitrary DNA strings into genetic orders, facilitating what the team calls an "end-to-end cyberbiological attack."

                  The synthetic gene engineering pipeline offered by these systems can be tampered with in browser-based attacks. Remote hackers could use malicious browser plugins, for example, to "inject obfuscated pathogenic DNA into an online order of synthetic genes."

                  In a case demonstrating the possibilities of this attack, the team cited residue Cas9 protein, using malware to transform this sequence into active pathogens. Cas9 protein, when using CRISPR protocols, can be exploited to "deobfuscate malicious DNA within the host cells," according to the team.

                  For an unwitting scientist processing the sequence, this could mean the accidental creation of dangerous substances, including synthetic viruses or toxic material.

                  "To regulate both intentional and unintentional generation of dangerous substances, most synthetic gene providers screen DNA orders which is currently the most effective line of defense against such attacks," commented Rami Puzis, head of the BGU Complex Networks Analysis Lab. "Unfortunately, the screening guidelines have not been adapted to reflect recent developments in synthetic biology and cyberwarfare."

                  A potential attack chain is outlined below:

                  "This attack scenario underscores the need to harden the synthetic DNA supply chain with protections against cyber-biological threats," Puzis added. "To address these threats, we propose an improved screening algorithm that takes into account in vivo gene editing."

                  Previous and related coverage

                  Have a tip? Get in touch securely via WhatsApp | Signal at +447713 025 499, or over at Keybase: charlie0

                  Related Topics:

                  By Charlie Osborne for Zero Day | November 30, 2020 -- 10:00 GMT (02:00 PST) | Topic: Security