Discovered: Purdue University researchers detect new Zika virus structure

Image credit: Kuhn and Rossmann research groups

New Delhi: In a step that would help better understand how the Zika virus infects host cells and spreads, researchers have discovered a new structure of the deadly virus.

Researchers from Purdue University analysed the high-resolution structure of the immature form of the Zika virus.

The research team found that the immature Zika virus had a similar structure to other related viruses, such as the West Nile virus and dengue fever.

The team of study led by Michael Rossmann and Richard Kuhn, both professors in Purdue's Department of Biological Sciences, comprised of postdoctoral research associate Vidya Mangala Prasad.

"It is, therefore, probable that the immature form of Zika also plays a role in virus infection and spread," said Michael Rossmann.

Zika belongs to a family of viruses called flaviviruses, which includes dengue, West Nile, yellow fever, Japanese encephalitis and tick-borne encephalitic viruses.

The study suggests that while only the mature forms of flaviviruses are considered infectious, the virus population secreted from host cells is a mixture of mature, partially mature and immature virus particles.

"I think these findings open the door to begin to explore the assembly process of the virus," said Richard Kuhn, director of the Purdue Institute for Inflammation, Immunology and Infectious Diseases, in the release. "We see clear differences between the structure of the immature virus and the mature virus. Not only are there differences in the outer structure, but the inner core must also undergo some significant changes during maturation. We need to study what these changes are and why they occur."

To determine the molecular structure, the team used a technique called cryo-electron microscopy, which allowed the researchers to observe the virus at a resolution of 9 Ångstroms, a high enough resolution to note tiny structural details.

Zika virus has been linked with microcephaly – a birth defect - which causes babies to be born with abnormally small heads and also with the autoimmune disorder Guillan-Barré syndrome.

The study funded by the National Institutes of Health was published online in the journal Nature Structural & Molecular Biology. It will also be published in a future print issue of the journal.