Crystal structure of Escherichia coli DEAH/RHA helicase HrpB.Xin, B.G., Chen, W.F., Rety, S., Dai, Y.X., Xi, X.G.
(2018) Biochem Biophys Res Commun 504: 334-339
- PubMed: 30190128
- DOI: https://doi.org/10.1016/j.bbrc.2018.08.191
- Primary Citation of Related Structures:
- PubMed Abstract:
RNA helicases are almost ubiquitous important enzymes that take part in multiple aspects of RNA metabolism. Prokaryotes encode fewer RNA helicases than eukaryotes, suggesting that individual prokaryotic RNA helicases may take on multiple roles. The specific functions and molecular mechanisms of bacterial DEAH/RHA helicases are poorly understood, and no structures are available of these bacterial enzymes. Here, we report the first crystal structure of the DEAH/RHA helicase HrpB of Escherichia coli in a complex with ADP•AlF 4 . It showed an atypical globular structure, consisting of two RecA domains, an HA2 domain and an OB domain, similar to eukaryotic DEAH/RHA helicases. Notably, it showed a unique C-terminal extension that has never been reported before. Activity assays indicated that EcHrpB binds RNA but not DNA, and does not exhibit unwinding activity in vitro. Thus, within cells, the EcHrpB may function in helicase activity-independent RNA metabolic processes.
Univ. Lyon, ENS de Lyon, Univ. Claude Bernard, CNRS UMR 5239, INSERM U1210, LBMC, 46 allée d'Italie Site Jacques Monod, F-69007, Lyon, France.