A dual role of divalent metal ions in catalysis and folding of RNase H1 from extreme halophilic archaeon Halobacterium sp. NRC-1.

ABSTRACT: RNase H1 from extreme halophilic archaeon Halobacterium sp. NRC-1 (Halo-RNH1) consists of an N-terminal domain with unknown function and a C-terminal RNase H domain. It is characterized by the high content of acidic residues on the protein surface. The far- and near-UV CD spectra of Halo-RNH1 suggested that Halo-RNH1 assumes a partially folded structure in the absence of salt and divalent metal ions. It requires either salt or divalent metal ions for folding. However, thermal denaturation of Halo-RNH1 analyzed in the presence of salt and/or divalent metal ions by CD spectroscopy suggested that salt and divalent metal ions independently stabilize the protein and thereby facilitate folding. Divalent metal ions stabilize the protein probably by binding mainly to the active site and suppressin

SUBMITTER: Tannous E 

PROVIDER: S-EPMC3678122 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature