Abstract
Proteolytic processing of the IBV 441-kDa 1a and 741-kDa la/1b fusion polyproteins to smaller mature products is mediated by two viral proteinases, namely, the papain-like Proteinase and the 3C-like proteinase (Fig. 1). The SC-like proteinase was identified as a 33-kDa protein in IBV-infected Vero cells (Lim et al., 2000). Characterization of the proteinase activities has shown that it cleaves the bulk of the polyproteins at conserved Q-S (G and N) dipeptide bonds, resulting in the release of more than ten mature products (Liu et al., 1994, 1997, 1998; Ng and Liu, 1998, 2000). It was shown to be associated with the membrane fraction in virus-infected cells by both cellular and biochemical studies (Ng and Liu, 2000).
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Ng, L.F.P., Xu, H.Y., Liu, D.X. (2001). Further Identification and Characterization of Products Processed from the Coronavirus Avian Infectious Bronchitis Virus (IBV) 1a Polyprotein by the 3C-like Proteinase. In: Lavi, E., Weiss, S.R., Hingley, S.T. (eds) The Nidoviruses. Advances in Experimental Medicine and Biology, vol 494. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-1325-4_45
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DOI: https://doi.org/10.1007/978-1-4615-1325-4_45
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