InterPro : IPR002320

Name  Threonine-tRNA ligase, class IIa Short Name  Thr-tRNA-ligase_IIa
Type  Family Description  Threonine-tRNA ligase (also known as Threonyl-tRNA synthetase) () exists as a monomer and belongs to class IIa. The enzyme fromEscherichia colirepresses the translation of its own mRNA. The crystal structure of the complex between tRNA(Thr) and ThrRS show structural features that reveal novel strategies for providing specificity in tRNA selection. These include an amino-terminal domain containing a novel protein fold that makes minor groove contacts with the tRNA acceptor stem. The enzyme induces a large deformation of the anticodon loop, resulting in an interaction between two adjacent anticodon bases, which accounts for their prominent role in tRNA identity and translational regulation. A zinc ion found in the active site is implicated in amino acid recognition/discrimination []. The zinc ion may act to ensure that only amino acids that possess a hydroxyl group attached to the beta-position are activated [].The aminoacyl-tRNA synthetase (also known as aminoacyl-tRNA ligase) catalyse the attachment of an amino acid to its cognate transfer RNA molecule in a highly specific two-step reaction. These proteins differ widely in size and oligomeric state, and have limited sequence homology []. The 20 aminoacyl-tRNA synthetases are divided into two classes, I and II. Class I aminoacyl-tRNA synthetases contain a characteristic Rossman fold catalytic domain and are mostly monomeric []. Class II aminoacyl-tRNA synthetases share an anti-parallel beta-sheet fold flanked by alpha-helices [], and are mostly dimeric or multimeric, containing at least three conserved regions [, , ]. However, tRNA binding involves an alpha-helical structure that is conserved between class I and class II synthetases. In reactions catalysed by the class I aminoacyl-tRNA synthetases, the aminoacyl group is coupled to the 2'-hydroxyl of the tRNA, while, in class II reactions, the 3'-hydroxyl site is preferred. The synthetases specific for arginine, cysteine, glutamic acid, glutamine, isoleucine, leucine, methionine, tyrosine, tryptophan and valine belong to class I synthetases. The synthetases specific for alanine, asparagine, aspartic acid, glycine, histidine, lysine, phenylalanine, proline, serine, and threonine belong to class-II synthetases. Based on their mode of binding to the tRNA acceptor stem, both classes of tRNA synthetases have been subdivided into three subclasses, designated 1a, 1b, 1c and 2a, 2b, 2c.
Paste the following link
 Feedback
  Feedback
Object Class
Object ID
Category
Your name:
Your email address:
Lab
Institute
Subject:
Message:
* Evidence
* Attachment size limit is 10 MB
Lists
This ProteinDomain isn't in any lists. Upload a list.

Sequence Features

GO Displayer

Proteins

InterPro protein domain ID --> Contigs

 

Other

0 Child Features

6 Contains

Id Name Short Name Type
IPR012947 Threonyl/alanyl tRNA synthetase, SAD tRNA_SAD Domain
IPR018163 Threonyl/alanyl tRNA synthetase, class II-like, putative editing domain Thr/Ala-tRNA-synth_IIc_edit Domain
IPR004154 Anticodon-binding Anticodon-bd Domain
IPR002314 Aminoacyl-tRNA synthetase, class II (G/ H/ P/ S), conserved domain aa-tRNA-synt_IIb_cons-dom Domain
IPR006195 Aminoacyl-tRNA synthetase, class II aa-tRNA-synth_II Domain
IPR015011 Threonyl-tRNA synthetase, editing domain, archaea Threonyl-tRNA_syn_edit_dom_arc Domain

0 Found In

0 Parent Features

8 Publications

First Author Title Year Journal Volume Pages
Perona JJ Structural basis for transfer RNA aminoacylation by Escherichia coli glutaminyl-tRNA synthetase. 1993 Biochemistry 32 8758-71
Delarue M The aminoacyl-tRNA synthetase family: modules at work. 1993 Bioessays 15 675-87
Cusack S Sequence, structural and evolutionary relationships between class 2 aminoacyl-tRNA synthetases. 1991 Nucleic Acids Res 19 3489-98
Schimmel P Classes of aminoacyl-tRNA synthetases and the establishment of the genetic code. 1991 Trends Biochem Sci 16 1-3
Sugiura I The 2.0 A crystal structure of Thermus thermophilus methionyl-tRNA synthetase reveals two RNA-binding modules. 2000 Structure 8 197-208
Eriani G Partition of tRNA synthetases into two classes based on mutually exclusive sets of sequence motifs. 1990 Nature 347 203-6
Sankaranarayanan R The structure of threonyl-tRNA synthetase-tRNA(Thr) complex enlightens its repressor activity and reveals an essential zinc ion in the active site. 1999 Cell 97 371-81
Sankaranarayanan R Zinc ion mediated amino acid discrimination by threonyl-tRNA synthetase. 2000 Nat Struct Biol 7 461-5



To cite PlanMine, please refer to the following publication:

Rozanski, A., Moon, H., Brandl, H., Martín-Durán, J. M., Grohme, M., Hüttner, K., Bartscherer, K., Henry, I., & Rink, J. C.
PlanMine 3.0—improvements to a mineable resource of flatworm biology and biodiversity
Nucleic Acids Research, gky1070. doi:10.1093/nar/gky1070 (2018)