Science is Fun Fridays!

Vampire Virus!

For the first time ever, a virus has been observed attaching to another virus.

The satellite virus (purple) literally bites the neck of the helper virus, on which it relies to complete its life cycle.

A team of undergraduates were analyzing the sequences of bacteriophages when they saw what they thought was a contamination.  They repeated the experiment and found the same, and upon further inspection found the presence of these helper viruses, 80% of which had a satellite.

They also found some without a satellite had bite marks, suggesting previous attachment.

Additional bioformatics done on a particular pair suggests their interaction is ancient, co-evolving for at least 100 million years.