M3i

@article{,

title = {Non-discriminating and discriminating aspartyl-tRNA synthetases differ in the anticodon-binding domain},

author = {C Charron and H Roy and M Blaise and R Giege and D Kern},

url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12660169},

isbn = {12660169},

year  = {2003},

date = {2003-01-01},

journal = {EMBO J},

volume = {22},

number = {7},

pages = {1632-1643},

abstract = {In most organisms, tRNA aminoacylation is ensured by 20 aminoacyl-tRNA synthetases (aaRSs). In eubacteria, however, synthetases can be duplicated as in Thermus thermophilus, which contains two distinct AspRSs. While AspRS-1 is specific, AspRS-2 is non-discriminating and aspartylates tRNA(Asp) and tRNA(Asn). The structure at 2.3 A resolution of AspRS-2, the first of a non-discriminating synthetase, was solved. It differs from that of AspRS-1 but has resemblance to that of discriminating and archaeal AspRS from Pyrococcus kodakaraensis. The protein presents non-conventional features in its OB-fold anticodon-binding domain, namely the absence of a helix inserted between two beta-strands of this fold and a peculiar L1 loop differing from the large loops known to interact with tRNA(Asp) identity determinant C36 in conventional AspRSs. In AspRS-2, this loop is small and structurally homologous to that in AsnRSs, including conservation of a proline. In discriminating Pyrococcus AspRS, the L1 loop, although small, lacks this proline and is not superimposable with that of AspRS-2 or AsnRS. Its particular status is demonstrated by a loop-exchange experiment that renders the Pyrococcus AspRS non-discriminating.},

note = {0261-4189 

Journal Article},

keywords = {Amino Acid  Support, Amino Acid Sequence  *Anticodon  Aspartate-tRNA Ligase/chemistry/*metabolism  Binding Sites  Models, Molecular  Molecular Sequence Data  Protein Conformation  Pyrococcus/enzymology  Sequence Homology, Non-U.S. Gov't  Thermus thermophilus/enzymology, Unité ARN},

pubstate = {published},

tppubtype = {article}

}