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Title: Toward Understanding Phosphoseryl-tRNA Cys Formation: The Crystal Structure of Methanococcus maripaludis Phosphoseryl-tRNA Synthetase

Abstract

A number of archaeal organisms generate Cys-tRNA{sup Cys} in a two-step pathway, first charging phosphoserine (Sep) onto tRNA{sup Cys} and subsequently converting it to Cys-tRNA{sup Cys}. We have determined, at 3.2-{angstrom} resolution, the structure of the Methanococcus maripaludis phosphoseryl-tRNA synthetase (SepRS), which catalyzes the first step of this pathway. The structure shows that SepRS is a class II, {alpha}{sub 4} synthetase whose quaternary structure arrangement of subunits closely resembles that of the heterotetrameric ({alpha}{beta}){sub 2} phenylalanyl-tRNA synthetase (PheRS). Homology modeling of a tRNA complex indicates that, in contrast to PheRS, a single monomer in the SepRS tetramer may recognize both the acceptor terminus and anticodon of a tRNA substrate. Using a complex with tungstate as a marker for the position of the phosphate moiety of Sep, we suggest that SepRS and PheRS bind their respective amino acid substrates in dissimilar orientations by using different residues.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930394
Report Number(s):
BNL-81116-2008-JA
Journal ID: ISSN 0027-8424; PNASA6; TRN: US200904%%674
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proceedings of the National Academy of Sciences of the USA; Journal Volume: 104; Journal Issue: 8
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMINO ACIDS; CRYSTAL STRUCTURE; CYSTEINE; LIGASES; MONOMERS; PHOSPHATES; RESIDUES; SIMULATION; SUBSTRATES; TRANSFER RNA; TUNGSTATES; national synchrotron light source

Citation Formats

Kamtekar ,S., Hohn, M., Park, h., Schnitzbauer, M., Sauerwald, A., Soll, D., and Steitz, T. Toward Understanding Phosphoseryl-tRNA Cys Formation: The Crystal Structure of Methanococcus maripaludis Phosphoseryl-tRNA Synthetase. United States: N. p., 2007. Web.
Kamtekar ,S., Hohn, M., Park, h., Schnitzbauer, M., Sauerwald, A., Soll, D., & Steitz, T. Toward Understanding Phosphoseryl-tRNA Cys Formation: The Crystal Structure of Methanococcus maripaludis Phosphoseryl-tRNA Synthetase. United States.
Kamtekar ,S., Hohn, M., Park, h., Schnitzbauer, M., Sauerwald, A., Soll, D., and Steitz, T. Mon . "Toward Understanding Phosphoseryl-tRNA Cys Formation: The Crystal Structure of Methanococcus maripaludis Phosphoseryl-tRNA Synthetase". United States. doi:.
@article{osti_930394,
title = {Toward Understanding Phosphoseryl-tRNA Cys Formation: The Crystal Structure of Methanococcus maripaludis Phosphoseryl-tRNA Synthetase},
author = {Kamtekar ,S. and Hohn, M. and Park, h. and Schnitzbauer, M. and Sauerwald, A. and Soll, D. and Steitz, T.},
abstractNote = {A number of archaeal organisms generate Cys-tRNA{sup Cys} in a two-step pathway, first charging phosphoserine (Sep) onto tRNA{sup Cys} and subsequently converting it to Cys-tRNA{sup Cys}. We have determined, at 3.2-{angstrom} resolution, the structure of the Methanococcus maripaludis phosphoseryl-tRNA synthetase (SepRS), which catalyzes the first step of this pathway. The structure shows that SepRS is a class II, {alpha}{sub 4} synthetase whose quaternary structure arrangement of subunits closely resembles that of the heterotetrameric ({alpha}{beta}){sub 2} phenylalanyl-tRNA synthetase (PheRS). Homology modeling of a tRNA complex indicates that, in contrast to PheRS, a single monomer in the SepRS tetramer may recognize both the acceptor terminus and anticodon of a tRNA substrate. Using a complex with tungstate as a marker for the position of the phosphate moiety of Sep, we suggest that SepRS and PheRS bind their respective amino acid substrates in dissimilar orientations by using different residues.},
doi = {},
journal = {Proceedings of the National Academy of Sciences of the USA},
number = 8,
volume = 104,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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  • No abstract prepared.
  • In this article, we describe for the first time the high-resolution crystal structure of a phenylalanine tRNA synthetase from the pathogenic bacterium Staphylococcus haemolyticus. We demonstrate the subtle yet important structural differences between this enzyme and the previously described Thermus thermophilus ortholog. We also explain the structure-activity relationship of several recently reported inhibitors. The native enzyme crystals were of poor quality -- they only diffracted X-rays to 3--5 {angstrom} resolution. Therefore, we have executed a rational surface mutagenesis strategy that has yielded crystals of this 2300-amino acid multidomain protein, diffracting to 2 {angstrom} or better. This methodology is discussed andmore » contrasted with the more traditional domain truncation approach.« less