Journal article

Publication year: 2018

Pages: 1253-1260

Journal: Journal of General Virology

Volume number: 99

Issue number: 9

ISSN: 0022-1317

eISSN: 1465-2099

Open access status: Bronze

DOI Link: https://doi.org/10.1099/jgv.0.001120

Publisher: Microbiology Society

Abstract: 
White bream virus (WBV), a poorly characterized plus-strand RNA virus infecting freshwater fish of the Cyprinidae family, is the prototype species of the genus Bafinivirus in the subfamily Torovirinae (family Coronaviridae, order Nidovirales). In common with other nidoviruses featuring >20 kilobase genomes, bafiniviruses have been predicted to encode an exoribonuclease (ExoN) in their replicase gene. Here, we used information on the substrate specificity of bafinivirus 3C-like proteases to express WBV ExoN in an active form in Escherichia coli. The 374-residue protein displayed robust 3'-to-5' exoribonuclease activity in the presence of Mg2+ ions and, unlike its coronavirus homologues, did not require a protein cofactor for activity. Characterization of mutant forms of ExoN provided support for predictions on putative active-site and conserved zinc-binding residues. WBV ExoN was revealed to be most active on double-stranded RNA substrates containing one or two non-paired 3'-terminal nucleotides, supporting its presumed role in increasing the fidelity of the bafinivirus RNA-dependent RNA polymerase.

Harvard Citation style: Durzynska, I., Sauerwald, M., Karl, N., Madhugiri, R. and Ziebuhr, J. (2018) Characterization of a bafinivirus exoribonuclease activity, Journal of General Virology, 99(9), pp. 1253-1260. https://doi.org/10.1099/jgv.0.001120

APA Citation style: Durzynska, I., Sauerwald, M., Karl, N., Madhugiri, R., & Ziebuhr, J. (2018). Characterization of a bafinivirus exoribonuclease activity. Journal of General Virology. 99(9), 1253-1260. https://doi.org/10.1099/jgv.0.001120