Highly conserved configuration of catalytic amino acid residues among calicivirus-encoded proteases.

ABSTRACT: A common feature of caliciviruses is the proteolytic processing of the viral polyprotein catalyzed by the viral 3C-like protease encoded in open reading frame 1 (ORF1). Here we report the identification and structural characterization of the protease domains and amino acid residues in sapovirus (SaV) and feline calicivirus (FCV). The in vitro expression and processing of a panel of truncated ORF1 polyproteins and corresponding mutant forms showed that the functional protease domain is 146 amino acids (aa) in SaV and 154 aa in FCV. Site-directed mutagenesis of the protease domains identified four amino acid residues essential to protease activities: H(31), E(52), C(116), and H(131) in SaV and H(39), E(60), C(122), and H(137) in FCV. A computer-assisted structural analysis showed that despit

SUBMITTER: Oka T 

PROVIDER: S-EPMC1933329 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature