Identification of a Ca2+-binding domain in the rubella virus nonstructural protease.

ABSTRACT: The rubella virus (RUB) nonstructural protein (NS) open reading frame (ORF) encodes a polypeptide precursor that is proteolytically self cleaved into two replicase components involved in viral RNA replication. A putative EF-hand Ca(2+)-binding motif that was conserved across different genotypes of RUB was predicted within the nonstructural protease that cleaves the precursor by using bioinformatics tools. To probe the metal-binding properties of this motif, we used an established grafting approach and engineered the 12-residue Ca(2+)-coordinating loop into a non-Ca(2+)-binding scaffold protein, CD2. The grafted EF-loop bound to Ca(2+) and its trivalent analogs Tb(3+) and La(3+) with K(d)s of 214, 47, and 14 microM, respectively. Mutations (D1210A and D1217A) of two of the potential Ca(2+)-

SUBMITTER: Zhou Y 

PROVIDER: S-EPMC1933374 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature