title: Inactivation of enveloped virus by laser-driven protein aggregation.
abstract: Ultrafast lasers in the visible and near-infrared range have emerged as a potential new method for pathogen reduction of blood products and pharmaceuticals. However, the mechanism of enveloped virus inactivation by this method is unknown. We report the inactivation as well as the molecular and structural effects caused by visible (425 nm) femtosecond laser irradiation on murine cytomegalovirus (MCMV), an enveloped, double-stranded DNA virus. Our results show that laser irradiation (1) caused a 5-log reduction in MCMV titer, (2) did not cause significant changes to the global structure of MCMV virions including membrane and capsid, as assessed by electron microscopy, (3) produced no evidence of double-strand breaks or crosslinking in MCMV genomic DNA, and (4) caused selective aggregation of viral capsid and tegument proteins. We propose a model in which ultrafast laser irradiation induces partial unfolding of viral proteins by disrupting hydrogen bonds and/or hydrophobic interactions, leading to aggregation of closely associated viral proteins and inactivation of the virus. These results provide new insight into the inactivation of enveloped viruses by visible femtosecond lasers at the molecular level, and help pave the way for the development of a new ultrafast laser technology for pathogen reduction.
authors.affiliation: Washington University School of Medicine, Department of Radiology, St. Louis, Missouri 63110, USA.
authors.forename: Shaw-Wei D
authors.initials: SW
authors.lastname: Tsen
authors.forename: Travis
authors.initials: T
authors.lastname: Chapa
authors.forename: Wandy
authors.initials: W
authors.lastname: Beatty
authors.forename: Kong-Thon
authors.initials: KT
authors.lastname: Tsen
authors.forename: Dong
authors.initials: D
authors.lastname: Yu
authors.forename: Samuel
authors.initials: S
authors.lastname: Achilefu
mesh_terms: D019281:Dimerization; D007834:Lasers; D018146:Muromegalovirus / Q000502:physiology* / Q000528:radiation effects*; D011829:Radiation Dosage; D019562:Viral Load / Q000502:physiology* / Q000528:radiation effects*; D014764:Viral Proteins / Q000378:metabolism*; D038301:Virus Inactivation / Q000528:radiation effects*
chemical_list: D014764:Viral Proteins