cit is a type of organic material and it is likely that some type of organism evolved to eat it. Plants, meat, algae, insects and bacteria are all eaten by different creatures, but scientists have now discovered a new item on the menu: viruses.
Header image: Under a microscope, chlorovirus attacks a piece of algae. (Cassidy Johnson/University of Nebraska at Lincoln)
Since viruses are found absolutely everywhere, it is inevitable that organisms will accidentally consume them. But researcher John DeLong, of the University of Nebraska-Lincoln, wanted to know whether microbes intentionally feed on viruses and whether such a diet could promote the physiological growth of individuals and the population growth of a community.
Selon DeLong:
They’re made of very good stuff: nucleic acids, lots of nitrogen and phosphorus. Everyone should want to eat them. So many things eat anything they can get their hands on. Surely he would have learned something by eating these delicious raw materials.
To test the hypothesis, DeLong and his team took samples of pond water, isolated several microbes, then added large amounts of chlorovirus, a freshwater inhabitant that infects green algae. Over the next few days, the team monitored the population size of viruses and other microbes to see if the latter ate the former.
As for the header image, under a microscope, chlorovirus attacks a piece of seaweed. (Kit Lee and Angie Fox/ University of Nebraska at Lincoln)
And, of course, one microbe in particular seemed to be feeding on viruses, a ciliate known as Halteria. In water samples with no other food source for the ciliates, Halteria populations increased 15-fold in two days, while chlorovirus levels decreased by 100. In virus-free control samples, Halteria did not develop at all .
In further tests, the team tagged the chlorovirus DNA with a fluorescent dye and found that the Halteria cells glowed rapidly. This confirmed that Halteria was indeed consuming the virus.
These experiments show that the new term “virovore” can now take its place among the terms herbivore, carnivore and others, Halteria being considered the earliest known vivoror. But of course it’s unlikely to be the only one, and researchers plan to continue studying the phenomenon, including its effects on food webs and larger systems like the carbon cycle.
The study published in the Proceedings of the National Academy of Sciences: Consuming viruses restores energy to food chains and offered by the University of Nebraska at Lincoln via Eurekalert: Eating viruses can fuel the growth, reproduction of the microorganism.
