2e7i: Difference between revisions

Revision as of 18:06, 21 February 2008

Crystal Structure of Sep-tRNA:Cys-tRNA Synthase from Archaeoglobus fulgidus

OverviewOverview

In the ancient organisms, methanogenic archaea, lacking the canonical cysteinyl-tRNA synthetase, Cys-tRNA(Cys) is produced by an indirect pathway, in which O-phosphoseryl-tRNA synthetase ligates O-phosphoserine (Sep) to tRNA(Cys) and Sep-tRNA:Cys-tRNA synthase (SepCysS) converts Sep-tRNA(Cys) to Cys-tRNA(Cys). In this study, the crystal structure of SepCysS from Archaeoglobus fulgidus has been determined at 2.4 A resolution. SepCysS forms a dimer, composed of monomers bearing large and small domains. The large domain harbors the seven-stranded beta-sheet, which is typical of the pyridoxal 5'-phosphate (PLP)-dependent enzymes. In the active site, which is located near the dimer interface, PLP is covalently bound to the side-chain of the conserved Lys209. In the proximity of PLP, a sulfate ion is bound by the side-chains of the conserved Arg79, His103, and Tyr104 residues. The active site is located deep within the large, basic cleft to accommodate Sep-tRNA(Cys). On the basis of the surface electrostatic potential, the amino acid residue conservation mapping, the position of the bound sulfate ion, and the substrate amino acid binding manner in other PLP-dependent enzymes, a binding model of Sep-tRNA(Cys) to SepCysS was constructed. One of the three strictly conserved Cys residues (Cys39, Cys42, or Cys247), of one subunit may play a crucial role in the catalysis in the active site of the other subunit.

About this StructureAbout this Structure

2E7I is a Single protein structure of sequence from Archaeoglobus fulgidus with and as ligands. Full crystallographic information is available from OCA.

ReferenceReference

Structural insights into the second step of RNA-dependent cysteine biosynthesis in archaea: crystal structure of Sep-tRNA:Cys-tRNA synthase from Archaeoglobus fulgidus., Fukunaga R, Yokoyama S, J Mol Biol. 2007 Jun 29;370(1):128-41. Epub 2007 May 4. PMID:17512006

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 ==Overview==
-In the ancient organisms, methanogenic archaea, lacking the canonical, cysteinyl-tRNA synthetase, Cys-tRNA(Cys) is produced by an indirect, pathway, in which O-phosphoseryl-tRNA synthetase ligates O-phosphoserine, (Sep) to tRNA(Cys) and Sep-tRNA:Cys-tRNA synthase (SepCysS) converts, Sep-tRNA(Cys) to Cys-tRNA(Cys). In this study, the crystal structure of, SepCysS from Archaeoglobus fulgidus has been determined at 2.4 A, resolution. SepCysS forms a dimer, composed of monomers bearing large and, small domains. The large domain harbors the seven-stranded beta-sheet, which is typical of the pyridoxal 5'-phosphate (PLP)-dependent enzymes. In, the active site, which is located near the dimer interface, PLP is, covalently bound to the side-chain of the conserved Lys209. In the, proximity of PLP, a sulfate ion is bound by the side-chains of the, conserved Arg79, His103, and Tyr104 residues. The active site is located, deep within the large, basic cleft to accommodate Sep-tRNA(Cys). On the, basis of the surface electrostatic potential, the amino acid residue, conservation mapping, the position of the bound sulfate ion, and the, substrate amino acid binding manner in other PLP-dependent enzymes, a, binding model of Sep-tRNA(Cys) to SepCysS was constructed. One of the, three strictly conserved Cys residues (Cys39, Cys42, or Cys247), of one, subunit may play a crucial role in the catalysis in the active site of the, other subunit.
+In the ancient organisms, methanogenic archaea, lacking the canonical cysteinyl-tRNA synthetase, Cys-tRNA(Cys) is produced by an indirect pathway, in which O-phosphoseryl-tRNA synthetase ligates O-phosphoserine (Sep) to tRNA(Cys) and Sep-tRNA:Cys-tRNA synthase (SepCysS) converts Sep-tRNA(Cys) to Cys-tRNA(Cys). In this study, the crystal structure of SepCysS from Archaeoglobus fulgidus has been determined at 2.4 A resolution. SepCysS forms a dimer, composed of monomers bearing large and small domains. The large domain harbors the seven-stranded beta-sheet, which is typical of the pyridoxal 5'-phosphate (PLP)-dependent enzymes. In the active site, which is located near the dimer interface, PLP is covalently bound to the side-chain of the conserved Lys209. In the proximity of PLP, a sulfate ion is bound by the side-chains of the conserved Arg79, His103, and Tyr104 residues. The active site is located deep within the large, basic cleft to accommodate Sep-tRNA(Cys). On the basis of the surface electrostatic potential, the amino acid residue conservation mapping, the position of the bound sulfate ion, and the substrate amino acid binding manner in other PLP-dependent enzymes, a binding model of Sep-tRNA(Cys) to SepCysS was constructed. One of the three strictly conserved Cys residues (Cys39, Cys42, or Cys247), of one subunit may play a crucial role in the catalysis in the active site of the other subunit.
 ==About this Structure==
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 [[Category: Single protein]]
 [[Category: Fukunaga, R.]]
-[[Category: RSGI, RIKEN.Structural.Genomics/Proteomics.Initiative.]]
+[[Category: RSGI, RIKEN Structural Genomics/Proteomics Initiative.]]
 [[Category: Yokoyama, S.]]
 [[Category: PLP]]
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 [[Category: structural genomics]]
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jan 23 12:48:29 2008''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:06:54 2008''