CRYSTAL-STRUCTURE OF THE RNA-BINDING DOMAIN FROM TRANSCRIPTION TERMINATION FACTOR-RHO

Transcription termination factor rho is an ATP-dependent hexameric hel icase found in most eubacterial species. The Escherichia coli rho mono mer consists of two domains, an RNA-binding domain (residues 1-130) an d an ATPase domain (residues 131-419). The ATPase domain is homologous to the beta subunit of F1-ATPase. Here, we report that the crystal st ructure of the RNA-binding domain of rho (rho130) at 1.55 Angstrom con firms that rho130 contains the oligosaccharide/oligonucleotide-binding (OB) fold, a five stranded beta-barrel. The beta-barrel of rho130 is also surprisingly similiar to the N-terminal beta-barrel of F1 ATPase, extending the applicability of F1 ATPase as a structural model for he xameric rho.