2GXU

HERA N-terminal domain in complex with orthophosphate, crystal form 1

Summary for 2GXU

• Entry DOI: 10.2210/pdb2gxu/pdb
• Related: 2GXQ 2GXS
• Descriptor: heat resistant RNA dependent ATPase, PHOSPHATE ION (3 entities in total)
• Functional Keywords: rna helicase, atomic resolution, amp complex, ribosome biogenesis, thermophilic, hydrolase
• Biological source: Thermus thermophilus HB27
• Total number of polymer chains: 1
• Total formula weight: 22437.92

Authors

Rudolph, M.G.,Klostermeier, D. (deposition date: 2006-05-09, release date: 2006-08-22, Last modification date: 2024-02-14)

Primary citation

Rudolph, M.G.,Heissmann, R.,Wittmann, J.G.,Klostermeier, D.
Crystal Structure and Nucleotide Binding of the Thermus thermophilus RNA Helicase Hera N-terminal Domain.
J.Mol.Biol., 351:731-743, 2006

PubMed Abstract: DEAD box RNA helicases use the energy of ATP hydrolysis to unwind double-stranded RNA regions or to disrupt RNA/protein complexes. A minimal RNA helicase comprises nine conserved motifs distributed over two RecA-like domains. The N-terminal domain contains all motifs involved in nucleotide binding, namely the Q-motif, the DEAD box, and the P-loop, as well as the SAT motif, which has been implicated in the coordination of ATP hydrolysis and RNA unwinding. We present here the crystal structure of the N-terminal domain of the Thermus thermophilus RNA helicase Hera in complex with adenosine monophosphate (AMP). Upon binding of AMP the P-loop adopts a partially collapsed or half-open conformation that is still connected to the DEAD box motif, and the DEAD box in turn is linked to the SAT motif via hydrogen bonds. This network of interactions communicates changes in the P-loop conformation to distant parts of the helicase. The affinity of AMP is comparable to that of ADP and ATP, substantiating that the binding energy from additional phosphate moieties is directly converted into conformational changes of the entire helicase. Importantly, the N-terminal Hera domain forms a dimer in the crystal similar to that seen in another thermophilic prokaryote. It is possible that this mode of dimerization represents the prototypic architecture in RNA helicases of thermophilic origin.

PubMed: 16890241
DOI: 10.1016/j.jmb.2006.06.065

Experimental method

X-RAY DIFFRACTION (1.67 Å)