2OHC

structural and mutational analysis of tRNA-intron splicing endonuclease from Thermoplasma acidophilum DSM1728

Summary for 2OHC

• Entry DOI: 10.2210/pdb2ohc/pdb
• Related: 2ohe
• Descriptor: tRNA-splicing endonuclease (2 entities in total)
• Functional Keywords: trna, intron, splicing, endonuclease, hydrolase
• Biological source: Thermoplasma acidophilum
• Total number of polymer chains: 2
• Total formula weight: 66513.27

Authors

Kim, Y.K.,Mizutani, K.,Rhee, K.H.,Lee, W.H.,Park, S.Y.,Hwang, K.Y. (deposition date: 2007-01-10, release date: 2007-11-27, Last modification date: 2024-10-30)

Primary citation

Kim, Y.K.,Mizutani, K.,Rhee, K.H.,Nam, K.H.,Lee, W.H.,Lee, E.H.,Kim, E.E.,Park, S.Y.,Hwang, K.Y.
Structural and Mutational Analysis of tRNA Intron-Splicing Endonuclease from Thermoplasma acidophilum DSM 1728: Catalytic Mechanism of tRNA Intron-Splicing Endonucleases
J.Bacteriol., 189:8339-8346, 2007

PubMed Abstract: In archaea, RNA endonucleases that act specifically on RNA with bulge-helix-bulge motifs play the main role in the recognition and excision of introns, while the eukaryal enzymes use a measuring mechanism to determine the positions of the universally positioned splice sites relative to the conserved domain of pre-tRNA. Two crystallographic structures of tRNA intron-splicing endonuclease from Thermoplasma acidophilum DSM 1728 (EndA(Ta)) have been solved to 2.5-A and 2.7-A resolution by molecular replacement, using the 2.7-A resolution data as the initial model and the single-wavelength anomalous-dispersion phasing method using selenomethionine as anomalous signals, respectively. The models show that EndA(Ta) is a homodimer and that it has overall folding similar to that of other archaeal tRNA endonucleases. From structural and mutational analyses of H236A, Y229F, and K265I in vitro, we have demonstrated that they play critical roles in recognizing the splice site and in cleaving the pre-tRNA substrate.

PubMed: 17827289
DOI: 10.1128/JB.00713-07

Experimental method

X-RAY DIFFRACTION (2.5 Å)