title: Characterization of a putative ancestor of coxsackievirus B5.
abstract: Like other RNA viruses, coxsackievirus B5 (CVB5) exists as circulating heterogeneous populations of genetic variants. In this study, we present the reconstruction and characterization of a probable ancestral virion of CVB5. Phylogenetic analyses based on capsid protein-encoding regions (the VP1 gene of 41 clinical isolates and the entire P1 region of eight clinical isolates) of CVB5 revealed two major cocirculating lineages. Ancestral capsid sequences were inferred from sequences of these contemporary CVB5 isolates by using maximum likelihood methods. By using Bayesian phylodynamic analysis, the inferred VP1 ancestral sequence dated back to 1854 (1807 to 1898). In order to study the properties of the putative ancestral capsid, the entire ancestral P1 sequence was synthesized de novo and inserted into the replicative backbone of an infectious CVB5 cDNA clone. Characterization of the recombinant virus in cell culture showed that fully functional infectious virus particles were assembled and that these viruses displayed properties similar to those of modern isolates in terms of receptor preferences, plaque phenotypes, growth characteristics, and cell tropism. This is the first report describing the resurrection and characterization of a picornavirus with a putative ancestral capsid. Our approach, including a phylogenetics-based reconstruction of viral predecessors, could serve as a starting point for experimental studies of viral evolution and might also provide an alternative strategy for the development of vaccines.
authors.affiliation: School of Natural Sciences, Linnaeus University, SE-391 82 Kalmar, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Gullberg
authors.forename: Conny
authors.initials: C
authors.lastname: Tolf
authors.forename: Nina
authors.initials: N
authors.lastname: Jonsson
authors.forename: Mick N
authors.initials: MN
authors.lastname: Mulders
authors.forename: Carita
authors.initials: C
authors.lastname: Savolainen-Kopra
authors.forename: Tapani
authors.initials: T
authors.lastname: Hovi
authors.forename: Marc
authors.initials: M
authors.lastname: Van Ranst
authors.forename: Philippe
authors.initials: P
authors.lastname: Lemey
authors.forename: Susan
authors.initials: S
authors.lastname: Hafenstein
authors.forename: A Michael
authors.initials: AM
authors.lastname: Lindberg
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D002460:Cell Line; D003384:Coxsackievirus Infections / Q000821:virology; D029822:Enterovirus B, Human / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D019143:Evolution, Molecular; D016679:Genome, Viral; D006801:Humans; D008957:Models, Genetic; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D040681:Structural Homology, Protein; D013997:Time Factors; D015678:Viral Structural Proteins / Q000737:chemistry / Q000235:genetics
chemical_list: D015678:Viral Structural Proteins