Summary information and primary citation
- PDB-id
-
3w3s;
DSSR-derived features in text and
JSON formats
- Class
- ligase-RNA
- Method
- X-ray (3.095 Å)
- Summary
- Crystal structure of a. aeolicus trnasec in complex
with m. kandleri serrs
- Reference
-
Itoh Y, Sekine S, Suetsugu S, Yokoyama S (2013):
"Tertiary
structure of bacterial selenocysteine tRNA."
Nucleic Acids Res., 41,
6729-6738. doi: 10.1093/nar/gkt321.
- Abstract
- Selenocysteine (Sec) is translationally incorporated
into proteins in response to the UGA codon. The tRNA
specific to Sec (tRNA(Sec)) is first ligated with serine by
seryl-tRNA synthetase (SerRS). In the present study, we
determined the 3.1 Å crystal structure of the tRNA(Sec)
from the bacterium Aquifex aeolicus, in complex with the
heterologous SerRS from the archaeon Methanopyrus kandleri.
The bacterial tRNA(Sec) assumes the L-shaped structure,
from which the long extra arm protrudes. Although the D-arm
conformation and the extra-arm orientation are similar to
those of eukaryal/archaeal tRNA(Sec)s, A. aeolicus
tRNA(Sec) has unique base triples, G14:C21:U8 and
C15:G20a:G48, which occupy the positions corresponding to
the U8:A14 and R15:Y48 tertiary base pairs of canonical
tRNAs. Methanopyrus kandleri SerRS exhibited serine
ligation activity toward A. aeolicus tRNA(Sec) in vitro.
The SerRS N-terminal domain interacts with the extra-arm
stem and the outer corner of tRNA(Sec). Similar
interactions exist in the reported tRNA(Ser) and SerRS
complex structure from the bacterium Thermus thermophilus.
Although the catalytic C-terminal domain of M. kandleri
SerRS lacks interactions with A. aeolicus tRNA(Sec) in the
present complex structure, the conformational flexibility
of SerRS is likely to allow the CCA terminal region of
tRNA(Sec) to enter the SerRS catalytic site.
