Genetically modified herpesviruses offer the promise of customizable therapeutics, including vaccines against a wide range of human pathogens. Although techniques such as bacterial artificial chromosome cloning have made inroads in the development of such therapeutics, they require multiple, time-consuming modifications.

Focusing on herpes simplex type 1 (HSV-1), a large DNA virusresearchers present a proof-of-concept approach to rapidly and efficiently introduce specific mutations into herpesvirus genomes.

Using yeast transformation-associated recombination, the authors demonstrate that the HSV-1 genome can be cloned in yeast as a series of 11 DNA fragments, which can be reassembled in yeast into a complete genome that exhibits the same infectious properties in mammalian cells as the wild-type strain.

In addition, the authors demonstrate how the technique can be applied to genome-wide virus engineering, generating modifications to single and multiple genes simultaneously. Although the findings are preliminary, the study offers a potential approach for viral engineering to rapidly develop vaccines and other therapeutic delivery systems. 

http://www.pnas.org/content/early/2017/09/18/1700534114