We have systematically screened the protein expression library from
hyperthermophilic archaeon Pyrococcus furiosus (
P. furiosus) using a
multi-structure oligo to search for novel RNA-binding proteins and found 21
RNA-binding protein candidates. The protein pool No.658, one of the 21
candidates, exhibits the RNA-binding activity. The PF1684 gene, which is
contained in the insert of the No.658 plasmid, is responsible for this
RNA-binding activity. PF1684-encoded protein is composed of a 249 amino acid
residues, which was purified to near homogeneity as a 28kDa polypeptide.
Homology search indicates it is acetylglutamate kinase. Our experiments suggest
that 55
C is the optimal temperature for its RNA-binding activity; this activity
is ATP independent; and the binding strength is related with temperature.
