1W94

Crystal Structure of Mil (Mth680), an archaeal Imp4-like protein

Summary for 1W94

• Entry DOI: 10.2210/pdb1w94/pdb
• Descriptor: PROBABLE BRIX-DOMAIN RIBOSOMAL BIOGENESIS PROTEIN (2 entities in total)
• Functional Keywords: archaeal imp4-brix domain, imp4 domain, brix domain, rna-binding protein
• Biological source: METHANOTHERMOBACTER THERMAUTOTROPHICUS
• Total number of polymer chains: 2
• Total formula weight: 36183.23

Authors

Ng, C.L.,Antson, A.A.,Ortiz-Lombardia, M. (deposition date: 2004-10-06, release date: 2005-01-19, Last modification date: 2024-10-16)

Primary citation

Ng, C.L.,Waterman, D.,Koonin, E.V.,Antson, A.A.,Ortiz-Lombardia, M.
Crystal Structure of Mil (Mth680): Internal Duplication and Similarity between the Imp4/Brix Domain and the Anticodon-Binding Domain of Class Iia Aminoacyl-tRNA Synthetases
Embo Rep., 6:140-, 2005

PubMed Abstract: Proteins of the Imp4/Brix superfamily are involved in ribosomal RNA processing, an essential function in all cells. We report the first structure of an Imp4/Brix superfamily protein, the Mil (for Methanothermobacter thermautotrophicus Imp4-like) protein (gene product Mth680), from the archaeon M. thermautotrophicus. The amino- and carboxy-terminal halves of Mil show significant structural similarity to one another, suggesting an origin by means of an ancestral duplication. Both halves show the same fold as the anticodon-binding domain of class IIa aminoacyl-tRNA synthetases, with greater conservation seen in the N-terminal half. This structural similarity, together with the charge distribution in Mil, suggests that Imp4/Brix superfamily proteins could bind single-stranded segments of RNA along a concave surface formed by the N-terminal half of their beta-sheet and a central alpha-helix. The crystal structure of Mil is incompatible with the presence, in the Imp4/Brix domain, of a helix-turn-helix motif that was proposed to comprise the RNA-binding moiety of the Imp4/Brix proteins.

PubMed: 15654320
DOI: 10.1038/SJ.EMBOR.7400328

Experimental method

X-RAY DIFFRACTION (2 Å)