Scientists have observed ‘vampire viruses’ in soil samples taken from Missouri and Maryland.
Unlike most bacterial viruses that engage with other infectious agents to replicate, these newly found microorganisms bite onto another virus’s neck to survive.
A team of researchers led by the University of Maryland Baltimore County (UMBC) found this ‘satellite’ virus lacks genes needed to integrate with the host cell’s DNA and latches on to its helper to infect the population – leaving behind ‘bite marks.’
The co-existing is believed to have evolved over at least 100 million years.
The first case of ‘vampire viruses’ (purple) has been observed by scientists, who found some infectious agents attach to the neck of another (blue) to ensure its life cycle
Biologist and lead author Tagide deCarvalho said: ‘When I saw it, I was like, ‘I can’t believe this.
‘No one has ever seen a bacteriophage – or any other virus– attach to another virus.’
The team studied a sample of satellite bacteriophage (a virus that infects bacterial cells), including a species of Streptomyces bacterium found in soil.
However, the bacteriophage typically has a gene for integration and does not directly attach to its helper.
The satellite in UMBC’s sample, named MiniFlayer by the students who isolated it, is the first known case of a satellite with no gene for integration.
An experiment showed that 80 percent (40 out of 50) helpers had a satellite bound at the neck
Because it cannot integrate into the host cell’s DNA, it must be near its helper—named MindFlayer—every time it enters a host cell if it is going to survive.
An experiment showed that 80 percent (40 out of 50) helpers had a satellite bound at the neck.
Given that, although the team did not directly prove this explanation, ‘Attaching now made total sense,’ said Ivan Erill, professor of biological sciences, ‘because otherwise, how are you going to guarantee that you are going to enter into the cell at the same time?’
More observations determined that MindFlayer and MiniFlayer have been co-evolving for a long time.
‘This satellite has been tuning in and optimizing its genome to be associated with the helper for, I would say, at least 100 million years,’ Erill said.