title: Reactions of beta-propiolactone with nucleobase analogues, nucleosides, and peptides: implications for the inactivation of viruses.
abstract: β-Propiolactone is often applied for inactivation of viruses and preparation of viral vaccines. However, the exact nature of the reactions of β-propiolactone with viral components is largely unknown. The purpose of the current study was to elucidate the chemical modifications occurring on nucleotides and amino acid residues caused by β-propiolactone. Therefore, a set of nucleobase analogues was treated with β-propiolactone, and reaction products were identified and quantified. NMR revealed at least one modification in either deoxyguanosine, deoxyadenosine, or cytidine after treatment with β-propiolactone. However, no reaction products were found from thymidine and uracil. The most reactive sides of the nucleobase analogues and nucleosides were identified by NMR. Furthermore, a series of synthetic peptides was used to determine the conversion of reactive amino acid residues by liquid chromatography-mass spectrometry. β-Propiolactone was shown to react with nine different amino acid residues. The most reactive residues are cysteine, methionine, and histidine and, to a lesser degree, aspartic acid, glutamic acid, tyrosine, lysine, serine, and threonine. Remarkably, cystine residues (disulfide groups) do not react with β-propiolactone. In addition, no reaction was observed for β-propiolactone with asparagine, glutamine, and tryptophan residues. β-Propiolactone modifies proteins to a larger extent than expected from current literature. In conclusion, the study determined the reactivity of β-propiolactone with nucleobase analogues, nucleosides, and amino acid residues and elucidated the chemical structures of the reaction products. The study provides detailed knowledge on the chemistry of β-propiolactone inactivation of viruses.
authors.affiliation: Unit Vaccinology, National Institute for Public Health and the Environment, 3720 BA Bilthoven, The Netherlands.
authors.forename: Joost P
authors.initials: JP
authors.lastname: Uittenbogaard
authors.forename: Bert
authors.initials: B
authors.lastname: Zomer
authors.forename: Peter
authors.initials: P
authors.lastname: Hoogerhout
authors.forename: Bernard
authors.initials: B
authors.lastname: Metz
mesh_terms: D004202:Disinfectants / Q000737:chemistry*; D009705:Nucleosides / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D011420:Propiolactone / Q000737:chemistry*; D014764:Viral Proteins / Q000737:chemistry*; D038301:Virus Inactivation; D014780:Viruses / Q000737:chemistry*
chemical_list: D004202:Disinfectants; D009705:Nucleosides; D010455:Peptides; D014764:Viral Proteins; D011420:Propiolactone