A team of researchers from Purdue University and The Catholic University of America has identified the atomic structure of a powerful "molecular motor" that packages DNA into the head segment of some viruses during their assembly, an essential step in their ability to multiply and infect new host organisms.
Michael Rossmann, Purdue's Hanley Distinguished Professor of Biological Sciences, has revealed that parts of the motor move in sequence like the pistons in a car's engine, progressively drawing the genetic material into the virus's head, scientifically known as capsid.
He said that the motor was essential to insert DNA into the capsid of the T4 virus, which is called a bacteriophage because it infects bacteria.
He added that the same kind of motor was also likely present in other viruses, such as the human herpes virus.
"Molecular motors in double-stranded DNA viruses have never been shown in such detail before," said Siyang Sun, a postdoctoral research associate working in Rossmann's lab.
"This research is allowing us to examine the inner workings of a virus packaging motor at the atomic level. This particular motor is very fast and powerful," said Venigalla B. Rao, a biology professor at Catholic University of America.
Since herpes and other viruses contain similar DNA packaging motors, such findings could someday help scientists design drugs that would interfere with the function of these motors and mitigate the result of some viral infections.
The findings also could have other future applications, such as developing alternatives to current antibiotics, creating methods to deliver genetic material to patients for gene therapy or creating tiny "nanomotors" in future machines.
"But this is very basic research, and it's far too soon to talk more about possible practical applications of this knowledge," Rossmann said.
An article on this study has been published in the online edition of the journal Cell.