The porcine reproductive and respiratory syndrome virus nsp2 cysteine protease domain possesses both trans- and cis-cleavage activities.

ABSTRACT: The N terminus of the replicase nonstructural protein 2 (nsp2) of porcine reproductive and respiratory syndrome virus (PRRSV) contains a putative cysteine protease domain (PL2). Previously, we demonstrated that deletion of either the PL2 core domain (amino acids [aa] 47 to 180) or the immediate downstream region (aa 181 to 323) is lethal to the virus. In this study, the PL2 domain was found to encode an active enzyme that mediates efficient processing of nsp2-3 in CHO cells. The PL2 protease possessed both trans- and cis-cleavage activities, which were distinguished by individual point mutations in the protease domain. The minimal size required to maintain these two enzymatic activities included nsp2 aa 47 to 240 (Tyr(47) to Cys(240)) and aa 47 to 323 (Tyr(47) to Leu(323)), respectively. I

SUBMITTER: Han J 

PROVIDER: S-EPMC2738230 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature