Q8TXK0 (SPCS_METKA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
O-phosphoseryl-tRNA(Sec) selenium transferase
EC=2.9.1.2

Alternative name(s):
Selenocysteine synthase
Short name=Sec synthase
Selenocysteinyl-tRNA(Sec) synthase
Sep-tRNA:Sec-tRNA synthase
Short name=SepSecS

Gene names

Name:	spcS
Ordered Locus Names:	MK0672

Organism

Methanopyrus kandleri (strain AV19 / DSM 6324 / JCM 9639 / NBRC 100938) [Reference proteome] [HAMAP]

Taxonomic identifier

190192 [NCBI]

Taxonomic lineage

cellular organisms › Archaea › Euryarchaeota › Methanopyri › Methanopyrales › Methanopyraceae › Methanopyrus › Methanopyrus kandleri

Protein attributes

Sequence length	431 AA.
Sequence status	Complete.
Protein existence	Inferred from homology

General annotation (Comments)

Function	Converts O-phosphoseryl-tRNA(Sec) to selenocysteinyl-tRNA(Sec) required for selenoprotein biosynthesis By similarity.
Catalytic activity	O-phospho-L-seryl-tRNA(Sec) + selenophosphate = L-selenocysteinyl-tRNA(Sec) + phosphate.
Cofactor	Pyridoxal phosphate By similarity.
Pathway	Aminoacyl-tRNA biosynthesis; selenocysteinyl-tRNA(Sec) biosynthesis; selenocysteinyl-tRNA(Sec) from L-seryl-tRNA(Sec) (archaeal/eukaryal route): step 2/2.
Subunit structure	Homotetramer By similarity.
Sequence similarities	Belongs to the SepSecS family.

Ontologies

Keywords
Biological process	Protein biosynthesis
Ligand	Pyridoxal phosphate RNA-binding Selenium tRNA-binding
Molecular function	Transferase
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	selenocysteinyl-tRNA(Sec) biosynthetic process Inferred from electronic annotation. Source: UniProtKB-UniPathway translation Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	pyridoxal phosphate binding Inferred from electronic annotation. Source: InterPro tRNA binding Inferred from electronic annotation. Source: UniProtKB-KW transferase activity, transferring selenium-containing groups Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 431	431	O-phosphoseryl-tRNA(Sec) selenium transferase		PRO_0000219882
Regions
	Region	1 – 36	36	Tetramerization By similarity
	Region	88 – 98	11	Phosphate loop (P-loop) By similarity
Sites
	Binding site	67	1	PLP By similarity
	Binding site	89	1	Substrate By similarity
	Binding site	90	1	Substrate By similarity
	Binding site	97	1	Substrate By similarity
	Binding site	298	1	Substrate By similarity
	Site	66	1	May act as a substrate filter by repelling compounds with a negatively charged alpha-carboxylate By similarity
Amino acid modifications
	Modified residue	269	1	N6-(pyridoxal phosphate)lysine By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q8TXK0 [UniParc]. Last modified June 1, 2002. Version 1. Checksum: 4557FD9AF640CA03	FASTA	431	47,589
	10 20 30 40 50 60 MRGLIPDHML ERGRTVLDSY REPVERLLSE RRMPEEGWPD DVIATFLWEL SRMDTDKDPK 70 80 90 100 110 120 AARIGEREAR VASRLAEESV FGFCHGVGRS GTLVDPQPKA PGASIMYALT NRLVTDFLRR 130 140 150 160 170 180 LGFRIEGAFV VPGATGLSIA LCLSALGEGE EVIYPYAAHK SPIKAVRLAG FGMRVVDTEI 190 200 210 220 230 240 EGDRIVVDPG DVEEALERSE SPAAVLSTLT FFPPRSSDPL PEIAELCEEY GVPHVVNAAY 250 260 270 280 290 300 GIQHEQYRDL LNRAIKRGRV DVVVSSTDKN LLTPVGGGIV YAPDEETLRE VSRAYPGRAS 310 320 330 340 350 360 AAPVAHALIS LLSLGMKGYR RLMRRQKECK ALLDELLEDL EARRDDVRVL DVDNPIASAV 370 380 390 400 410 420 AVEGHDPVDL AARLYVRRVT GPRGVRADDP FGTSRLRGYH SNYITINAAI GVREEDVKTA 430 VERLERELEG E

References

[1]

"The complete genome of hyperthermophile Methanopyrus kandleri AV19 and monophyly of archaeal methanogens." Slesarev A.I., Mezhevaya K.V., Makarova K.S., Polushin N.N., Shcherbinina O.V., Shakhova V.V., Belova G.I., Aravind L., Natale D.A., Rogozin I.B., Tatusov R.L., Wolf Y.I., Stetter K.O., Malykh A.G., Koonin E.V., Kozyavkin S.A. Proc. Natl. Acad. Sci. U.S.A. 99:4644-4649(2002) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: AV19 / DSM 6324 / JCM 9639 / NBRC 100938.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AE009439 Genomic DNA. Translation: AAM01887.1.
RefSeq	NP_613957.1. NC_003551.1.
3D structure databases
ProteinModelPortal	Q8TXK0.
SMR	Q8TXK0. Positions 1-426.
ModBase	Search...
Protein-protein interaction databases
STRING	190192.MK0672.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
EnsemblBacteria	AAM01887; AAM01887; MK0672.
GeneID	1476773.
KEGG	mka:MK0672.
Phylogenomic databases
eggNOG	COG0076.
HOGENOM	HOG000254245.
KO	K03341.
OMA	HKSPIKA.
ProtClustDB	CLSK876261.
Enzyme and pathway databases
UniPathway	UPA00906; UER00898.
Family and domain databases
Gene3D	3.40.640.10. 1 hit.
InterPro	IPR015424. PyrdxlP-dep_Trfase. IPR015421. PyrdxlP-dep_Trfase_major_sub1. IPR019872. Sec-tRNA_Se_transferase. IPR008829. SLA/LP_auto_ag. [Graphical view]
PANTHER	PTHR12944. PTHR12944. 1 hit.
Pfam	PF05889. SLA_LP_auto_ag. 1 hit. [Graphical view]
PIRSF	PIRSF017689. SepSecS. 1 hit.
SUPFAM	SSF53383. PyrdxlP-dep_Trfase_major. 1 hit.
TIGRFAMs	TIGR03531. selenium_SpcS. 1 hit.
ProtoNet	Search...

Entry information

Entry name

SPCS_METKA

Accession

Primary (citable) accession number: Q8TXK0

Entry history

Integrated into UniProtKB/Swiss-Prot:	March 29, 2005
Last sequence update:	June 1, 2002
Last modified:	May 1, 2013
This is version 54 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program