Reviewed, UniProtKB/Swiss-Prot P05719 (T1SK_ECOLI)

Names and origin

Protein names

Recommended name:
    Type-1 restriction enzyme EcoKI specificity protein
      Short name=S.EcoKI
Alternative name(s):
    Type I restriction enzyme EcoKI specificity protein
      Short name=S protein

Gene names

Name:	hsdS
Synonyms:	hss
Ordered Locus Names:	b4348, JW4311

Organism

Escherichia coli (strain K12) [Complete proteome] [HAMAP]

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia

Protein attributes

Sequence length	464 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	The M and S subunits together form a methyltransferase (MTase) that methylates two adenine residues in complementary strands of a bipartite DNA recognition sequence. In the presence of the R subunit the complex can also act as an endonuclease, binding to the same target sequence but cutting the DNA some distance from this site. Whether the DNA is cut or modified depends on the methylation state of the target sequence. When the target site is unmodified, the DNA is cut. When the target site is hemimethylated, the complex acts as a maintenance MTase modifying the DNA so that both strands become methylated. Subunit S dictates DNA sequences specificity. The EcoKI enzyme recognizes 5'-AACN6GTGC-3'.
Subunit structure	The type I restriction/modification system is composed of three polypeptides R, M and S.
Domain	Contains two DNA recognition domains, each specifying recognition of one of the two defined components of the target sequence.
Sequence similarities	Belongs to the type-I restriction system S methylase family.

Ontologies

Keywords
Biological process	Restriction system
Ligand	DNA-binding
Technical term	Complete proteome Direct protein sequencing
Gene Ontology (GO)
Biological process	DNA restriction-modification system Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	DNA binding Inferred from electronic annotation. Source: UniProtKB-KW protein binding Inferred from physical interaction. Source: IntAct
Complete GO annotation...

Binary interactions

With	Entry	#Exp.	IntAct	Notes
hflB	P0AAI3	1	EBI-1135164,EBI-548381

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 464	464	Type-1 restriction enzyme EcoKI specificity protein		PRO_0000198035

Sequences

	Sequence		Length	Mass (Da)
	P05719-1 [UniParc]. Last modified November 1, 1988. Version 1. Checksum: 1D651D0716B08C04	FASTA	464	51,395
	10 20 30 40 50 60 MSAGKLPEGW VIAPVSTVTT LIRGVTYKKE QAINYLKDDY LPLIRANNIQ NGKFDTTDLV 70 80 90 100 110 120 FVPKNLVKES QKISPEDIVI AMSSGSKSVV GKSAHQHLPF ECSFGAFCGV LRPEKLIFSG 130 140 150 160 170 180 FIAHFTKSSL YRNKISSLSA GANINNIKPA SFDLINIPIP PLAEQKIIAE KLDTLLAQVD 190 200 210 220 230 240 STKARFEQIP QILKRFRQAV LGGAVNGKLT EKWRNFEPQH SVFKKLNFES ILTELRNGLS 250 260 270 280 290 300 SKPNESGVGH PILRISSVRA GHVDQNDIRF LECSESELNR HKLQDGDLLF TRYNGSLEFV 310 320 330 340 350 360 GVCGLLKKLQ HQNLLYPDKL IRARLTKDAL PEYIEIFFSS PSARNAMMNC VKTTSGQKGI 370 380 390 400 410 420 SGKDIKSQVV LLPPVKEQAE IVRRVEQLFA YADTIEKQVN NALARVNNLT QSILAKAFRG 430 440 450 460 ELTAQWRAEN PDLISGENSA AALLEKIKAE RAASGGKKAS RKKS

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Sequence diversity among related genes for recognition of specific targets in DNA molecules." Gough J.A., Murray N.E. J. Mol. Biol. 166:1-19(1983) [PubMed: 6304321] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: K12.
[2]	"Analysis of the Escherichia coli genome VI: DNA sequence of the region from 92.8 through 100 minutes." Burland V.D., Plunkett G. III, Sofia H.J., Daniels D.L., Blattner F.R. Nucleic Acids Res. 23:2105-2119(1995) [PubMed: 7610040] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[3]	"The complete genome sequence of Escherichia coli K-12." Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V., Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F., Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B., Shao Y. Science 277:1453-1474(1997) [PubMed: 9278503] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[4]	"Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 and W3110." Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T. Mol. Syst. Biol. 2:E1-E5(2006) [PubMed: 16738553] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[5]	"Tyrosine 27 of the specificity polypeptide of EcoKI can be UV crosslinked to a bromodeoxyuridine-substituted DNA target sequence." Chen A., Powell L.M., Dryden D.T., Murray N.E., Brown T. Nucleic Acids Res. 23:1177-1183(1995) [PubMed: 7739896] [Abstract] Cited for: PARTIAL PROTEIN SEQUENCE.

Cross-references

Sequence databases
EMBLGenBankDDBJ	V00288 Genomic DNA. Translation: CAA23554.1. U14003 Genomic DNA. Translation: AAA97245.1. U00096 Genomic DNA. Translation: AAC77304.1. AP009048 Genomic DNA. Translation: BAE78338.1.
PIR	NDECKS. A30369.
RefSeq	AP_004837.1. NP_418768.1.
3D structure databases
ModBase	Search...
Protein-protein interaction databases
IntAct	P05719. 1 interaction.
Protein family/group databases
REBASE	3646. S.EcoKI.
Genome annotation databases
GeneID	948867.
GenomeReviews	Gene locus JW4311 in contig AP009048_GR. Gene locus b4348 in contig U00096_GR.
KEGG	ecj:JW4311. eco:b4348.
Organism-specific databases
EchoBASE	EB0455.
EcoGene	EG10460. hsdS.
CMR	Search...
Phylogenomic databases
HOGENOM	P05719.
OMA	P05719. AQVDTLK.
Enzyme and pathway databases
BioCyc	EcoCyc:EG10460-MON.
Family and domain databases
InterPro	IPR000055. Restrict_endonuc_I_S_EcoBI. [Graphical view]
Pfam	PF01420. Methylase_S. 2 hits. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

T1SK_ECOLI

Accession

Primary (citable) accession number: P05719
Secondary accession number(s): Q2M5W8

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 1, 1988
Last sequence update:	November 1, 1988
Last modified:	June 16, 2009
This is version 75 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)