1htt
From Proteopedia
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
| - | The crystal structure at 2.6 A of the histidyl-tRNA synthetase from | + | The crystal structure at 2.6 A of the histidyl-tRNA synthetase from Escherichia coli complexed with histidyl-adenylate has been determined. The enzyme is a homodimer with a molecular weight of 94 kDa and belongs to the class II of aminoacyl-tRNA synthetases (aaRS). The asymmetric unit is composed of two homodimers. Each monomer consists of two domains. The N-terminal catalytic core domain contains a six-stranded antiparallel beta-sheet sitting on two alpha-helices, which can be superposed with the catalytic domains of yeast AspRS, and GlyRS and SerRS from Thermus thermophilus with a root-mean-square difference on the C alpha atoms of 1.7-1.9 A. The active sites of all four monomers are occupied by histidyl-adenylate, which apparently forms during crystallization. The 100 residue C-terminal alpha/beta domain resembles half of a beta-barrel, and provides an independent domain oriented to contact the anticodon stem and part of the anticodon loop of tRNA(His). The modular domain organization of histidyl-tRNA synthetase reiterates a repeated theme in aaRS, and its structure should provide insight into the ability of certain aaRS to aminoacylate minihelices and other non-tRNA molecules. |
==About this Structure== | ==About this Structure== | ||
| Line 14: | Line 14: | ||
[[Category: Histidine--tRNA ligase]] | [[Category: Histidine--tRNA ligase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Arnez, J | + | [[Category: Arnez, J G.]] |
| - | [[Category: Francklyn, C | + | [[Category: Francklyn, C S.]] |
| - | [[Category: Harris, D | + | [[Category: Harris, D C.]] |
[[Category: Mitschler, A.]] | [[Category: Mitschler, A.]] | ||
[[Category: Moras, D.]] | [[Category: Moras, D.]] | ||
| Line 26: | Line 26: | ||
[[Category: synthetase]] | [[Category: synthetase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:04:45 2008'' |
Revision as of 11:04, 21 February 2008
|
HISTIDYL-TRNA SYNTHETASE
Overview
The crystal structure at 2.6 A of the histidyl-tRNA synthetase from Escherichia coli complexed with histidyl-adenylate has been determined. The enzyme is a homodimer with a molecular weight of 94 kDa and belongs to the class II of aminoacyl-tRNA synthetases (aaRS). The asymmetric unit is composed of two homodimers. Each monomer consists of two domains. The N-terminal catalytic core domain contains a six-stranded antiparallel beta-sheet sitting on two alpha-helices, which can be superposed with the catalytic domains of yeast AspRS, and GlyRS and SerRS from Thermus thermophilus with a root-mean-square difference on the C alpha atoms of 1.7-1.9 A. The active sites of all four monomers are occupied by histidyl-adenylate, which apparently forms during crystallization. The 100 residue C-terminal alpha/beta domain resembles half of a beta-barrel, and provides an independent domain oriented to contact the anticodon stem and part of the anticodon loop of tRNA(His). The modular domain organization of histidyl-tRNA synthetase reiterates a repeated theme in aaRS, and its structure should provide insight into the ability of certain aaRS to aminoacylate minihelices and other non-tRNA molecules.
About this Structure
1HTT is a Single protein structure of sequence from Escherichia coli with as ligand. Active as Histidine--tRNA ligase, with EC number 6.1.1.21 Known structural/functional Sites: , , and . Full crystallographic information is available from OCA.
Reference
Crystal structure of histidyl-tRNA synthetase from Escherichia coli complexed with histidyl-adenylate., Arnez JG, Harris DC, Mitschler A, Rees B, Francklyn CS, Moras D, EMBO J. 1995 Sep 1;14(17):4143-55. PMID:7556055
Page seeded by OCA on Thu Feb 21 13:04:45 2008
