Op-Ed: Viruses as a huge resource? Virus-eating plankton show the way

Posted Dec 2, 2020 by Paul Wallis
Everyone knew viruses were on the rampage long before the pandemic. Are they unstoppable? No; in fact some marine microbes are virus-hunting specialists, and there are some interesting new findings with that.
This colorized transmission electron micrograph shows H1N1 influenza virus particles like hemaggluti...
This colorized transmission electron micrograph shows H1N1 influenza virus particles like hemagglutinin and neuraminidase. Surface proteins on the virus particles are shown in black. National Institutes of Health (NIH)
U.S. National Institutes of Health
The microbes in question are called Picozoa, which means “tiny animals”. They’re effectively plankton. Research indicates that they’re highly efficient predators of viruses. A short but spectacular paper on the joint study on the Picozoa was done by a virtual shopping list of top-tier research organizations:
• Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
• Department of Marine Biology, Texas A&M University at Galveston, Galveston, TX, United States
• Department of Human Genetics, University of Utah, Salt Lake City, UT, United States
• Division of Ocean Sciences, National Science Foundation, Alexandria, VA, United States
• Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
Please do watch the video for a friendly introduction to the issues in this research. Anton always does an excellent job of explaining the situations and walking people through complex science.
The resulting paper has basically turned the standard picture of marine viral presences on its head. It seems these plankton are major virus destroyers. They eat viruses. Two studies, in the Mediterranean and the Gulf of Maine, showed a lot of remnant viral DNA in the water.
These were the remains of “free particle” viruses, i.e., likely those viruses released after cellular destruction. (Viruses can release a lot of newly replicated viruses in this phase, which also helps build the huge marine viral populations.)
These are the shrapnel of the organisms, and the basis of what’s called “viral shunt”. Viral shunt is a very big deal environmentally; it’s a broad-spectrum ecological process which includes recycling nutrients for marine life. This supports the all-important lower food chain, thus supporting the rest of the food chain.
This is a simple equation, but it’s pretty spectacular:
• Typically, when viruses “explode” a cell, fragments of DNA of the victim organism are left around in large quantities.
• If viruses are eaten, there’s more viral DNA.
• The two studies indicated different rates of both processes, but the ratios (51% for the Gulf of Maine and 35% for the Mediterranean) indicate a huge turnover of viruses. The research indicated that a large variety of viruses were consumed, too. Seems the Picozoa aren’t fussy about which viruses they eat.
Eating lots of viruses is apparently a very good deal for the Picozoa plankton. The viruses contain a lot of nutrients for plankton, including carbon, phosphorous, nitrogen, and other useful dietary additions. (Humans eat all these things in huge quantities too, which is leading the odd logic below.)
The apparently large hits to the viral population by the Picozoa are well worth study in their own right. How does the ratio of viral DNA reflect the viral population, and in turn reflect the state of the non-viral organisms in any given location? What happens if an area runs out of viruses?
This research may well have found a real breakthrough in fundamental marine microecology. It could help with fisheries, aquaculture, marine ecosystem health, and anything else to do with practical marine biology.
Ah…Are we missing a trick here?
Viruses are traditionally considered very high risk problems, with plenty of reason. Many of them are dangerous. They’re difficult to manage. Their pathology, notably that of the much-cursed coronaviruses, is particularly tricky.
But… The fact that these microbes eat viruses got me thinking. Hunting and eating a virus looks like hard work, but the Picozoa seem to be on a winning deal. Obviously, they can destroy viruses, and therefore must have some way of breaking them down.
That’s not of itself a simple process. Some microbial and fungal enzymes make industrial chemicals look positively feeble. The Picozoa have apparently got their viral-killing processes down to a fine art, effective enough for them to thrive. So what’s the process? Too soon to tell.
The viral shunt mechanism, however, is better known and much easier to understand in depth. This process turns organic waste into accessible nutrients for microbiota and plankton. Recycling ex-viruses seems pretty straightforward, at least in theory.
A leap of odd logic
Viruses are a truly tough, expensive, global pest in most cases. They contain a lot of useful nutrients, just in a very dangerous package. Viral mass on Earth could well be in the tens of billions of tons.
So why not turn viruses into massive reservoirs of nutrients? Maybe even “virus burgers”, synthetic protein with built-in or added nutrients from viruses? How about animal feed? Viruses can replicate like almost nothing else. They’re “sustainable” in volumes few other organic materials could approach.
These proteins would obviously need to be fully digestible for consumption, like no “cardboard” compounds, but what if we could mass produce tons of viral steak? (No promises about the taste, though.)
As for harvesting materials from viral biomasses, that’s a lot simpler. Artificial viral shunt, backed up by some basic separation technologies, should do the trick. There’d be vast amounts of raw materials to be obtained.
Some of those materials, notably nitrogen, have immediate uses, too, as in fertilizer and basic chemical and biochemical processes. As carbon sinks and sources of carbon and phosphorous recovery, viruses could be pretty handy, too. The sheer scale of viral populations could turn these nuisances into major global commodity assets.
Environmental benefits?
The main benefit at the moment would be reducing viral pressure on enfeebled environments. This would be very useful for environments which are already under enough stress.
Any way you look at it, harnessing viruses as macroeconomic assets makes sense. They’re costing a fortune to manage. The global viral population is almost incalculable in scale and degrees of risk. If we can get a handle on the viruses, a huge range of issues could become a lot less risky and a lot more profitable.
Slight digression
Just a thought - The viral shunt process could also be a clue to taking the sting out of marauding viruses like coronaviruses, Ebola and other very much- unwanted viral representatives. There must be some non-marine version of Picozoa. What if a land-based Picozoan or several could be brought into service as a public health asset? Reduce the population of these nuisances, and reduce the risk? Should work.