Reviewed, UniProtKB/Swiss-Prot Q779K4 (STXA_BP788)

Names and origin

Protein names

Recommended name:
    Shiga toxin subunit A
    EC=3.2.2.22

Gene names

Name:

stxA

Organism

Shigella phage 7888 (Shigella sonnei bacteriophage 7888)

Taxonomic identifier

138946 [NCBI]

Taxonomic lineage

Viruses › dsDNA viruses, no RNA stage › Caudovirales › Podoviridae

Virus host

Shigella sonnei [TaxID: 624]

Protein attributes

Sequence length	315 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Inferred from homology.

General annotation (Comments)

Function	The A subunit is responsible for inhibiting protein synthesis through the catalytic inactivation of 60S ribosomal subunits. After endocytosis, the A subnit is cleaved by furin in two fragments, A1 and A2: A1 is the catalytically active fragment, and A2 is essential for holotoxin assembly with the B subunits By similarity.
Catalytic activity	Endohydrolysis of the N-glycosidic bond at one specific adenosine on the 28S rRNA.
Subunit structure	Shiga toxin contains a single subunit A and five copies of subunit B By similarity.
Sequence similarities	Belongs to the ribosome-inactivating protein family.

Ontologies

Keywords
Domain	Signal
Molecular function	Hydrolase Protein synthesis inhibitor Toxin
PTM	Disulfide bond
Gene Ontology (GO)
Biological process	negative regulation of translation Inferred from electronic annotation. Source: UniProtKB-KW pathogenesis Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	rRNA N-glycosylase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 22	22	Potential
	Chain	23 – 315	293	Shiga toxin subunit A		PRO_0000312304
Regions
	Region	23 – 273	251	A1
	Region	274 – 315	42	A2
Sites
	Active site	189	1	By similarity
	Site	273 – 274	2	Cleavage; by furin By similarity
Amino acid modifications
	Disulfide bond	264 ↔ 283		By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q779K4-1 [UniParc]. Last modified July 5, 2004. Version 1. Checksum: 8A423DF7ABF58F30	FASTA	315	34,814
	10 20 30 40 50 60 MKIIIFRVLT FFFVIFSVNV VAKEFTLDFS TAKTYVDSLN VIRSAIGTPL QTISSGGTSL 70 80 90 100 110 120 LMIDSGTGDN LFAVDVRGID PEEGRFNNLR LIVERNNLYV TGFVNRTNNV FYRFADFSHV 130 140 150 160 170 180 TFPGTTAVTL SGDSSYTTLQ RVAGISRTGM QINRHSLTTS YLDLMSHSGT SLTQSVARAM 190 200 210 220 230 240 LRFVTVTAEA LRFRQIQRGF RTTLDDLSGR SYVMTAEDVD LTLNWGRLSS VLPDYHGQDS 250 260 270 280 290 300 VRVGRISFGS INAILGSVAL ILNCHHHASR VARMASDEFP SMCPADGRVR GITHNKILWD 310 SSTLGAILMR RTISS

References

[1]	"Isolation of Shigella sonnei lysogenic for a bacteriophage encoding gene for production of Shiga toxin." Beutin L., Strauch E., Fischer I. Lancet 353:1498-1498(1999) [PubMed: 10232325] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Characterization of a Shiga toxin-encoding temperate bacteriophage of Shigella sonnei." Strauch E., Lurz R., Beutin L. Infect. Immun. 69:7588-7595(2001) [PubMed: 11705937] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AJ132761 Genomic DNA. Translation: CAA10763.1. AJ279086 Genomic DNA. Translation: CAC12887.1.
3D structure databases
SMR	Q779K4. Positions 23-312.
ModBase	Search...
Family and domain databases
InterPro	IPR001574. Ribosome_inactivat_prot. IPR017988. Ribosome_inactivat_prot_CS. IPR016138. Ribosome_inactivat_prot_sub1. IPR016139. Ribosome_inactivat_prot_sub2. IPR016331. Shiga-like_toxin_subunit_A. [Graphical view]
Gene3D	G3DSA:3.40.420.10. Ribosome_inactivat_prot_sub1. 1 hit. G3DSA:4.10.470.10. Ribosome_inactivat_prot_sub2. 1 hit.
Pfam	PF00161. RIP. 1 hit. [Graphical view]
PIRSF	PIRSF001924. Shigella_toxin_subunit_A. 1 hit.
PROSITE	PS00275. SHIGA_RICIN. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

STXA_BP788

Accession

Primary (citable) accession number: Q779K4
Secondary accession number(s): Q7B2T8

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 4, 2007
Last sequence update:	July 5, 2004
Last modified:	June 16, 2009
This is version 30 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

Virus (Virus annotation project)