Mutation Analysis of the GDD Sequence Motif of a Calicivirus RNA-Dependent RNA Polymerase

AUTOR(ES)

Vázquez, Ana López

FONTE

American Society for Microbiology

RESUMO

The RNA-dependent RNA polymerase from rabbit hemorrhagic disease virus, a calicivirus, is known to have a conserved GDD amino acid motif and several additional regions of sequence homology with all types of polymerases. To test whether both aspartic acid residues are in fact involved in the catalytic activity and metal ion coordination of the enzyme, several defined mutations have been made in order to replace them by glutamate, asparagine, or glycine. All six mutant enzymes were produced in Escherichia coli, and their in vitro poly(U) polymerase activity was characterized. The results demonstrated that the first aspartate residue was absolutely required for enzyme function and that some flexibility existed with respect to the second, which could be replaced by glutamate.

Documentos Relacionados

• Mutation of the aspartic acid residues of the GDD sequence motif of poliovirus RNA-dependent RNA polymerase results in enzymes with altered metal ion requirements for activity.
• Proteinase-Polymerase Precursor as the Active Form of Feline Calicivirus RNA-Dependent RNA Polymerase
• Reticulocyte RNA-Dependent RNA Polymerase
• RNA-dependent RNA polymerase of tobacco plants
• Identification of a C-Terminal Regulatory Motif in Hepatitis C Virus RNA-Dependent RNA Polymerase: Structural and Biochemical Analysis