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P02920 (LACY_ECOLI) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 139. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (3) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Lactose permease
Alternative name(s):
Lactose-proton symport
Gene names
Name:lacY
Ordered Locus Names:b0343, JW0334
OrganismEscherichia coli (strain K12) [Reference proteome] [HAMAP]
Taxonomic identifier83333 [NCBI]
Taxonomic lineageBacteriaProteobacteriaGammaproteobacteriaEnterobacterialesEnterobacteriaceaeEscherichia

Protein attributes

Sequence length417 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Responsible for transport of beta-galactosides into the cell, with the concomitant import of a proton (symport system).

Subunit structure

Monomer.

Subcellular location

Cell inner membrane; Multi-pass membrane protein.

Sequence similarities

Belongs to the LacY/RafB permease family.

Mass spectrometry

Molecular mass is 47357 Da from positions 1 - 417. Determined by ESI. Ref.12

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 417417Lactose permease
PRO_0000196184

Regions

Topological domain1 – 77Cytoplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane8 – 3427Helical; Name=1
Topological domain35 – 417Periplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane42 – 7029Helical; Name=2
Topological domain71 – 744Cytoplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane75 – 10026Helical; Name=3
Topological domain101 – 1044Periplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane105 – 12925Helical; Name=4
Topological domain130 – 14011Cytoplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane141 – 16323Helical; Name=5
Topological domain164 – 1663Periplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane167 – 18620Helical; Name=6
Topological domain187 – 22034Cytoplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane221 – 24929Helical; Name=7
Topological domain250 – 2534Periplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane254 – 27825Helical; Name=8
Topological domain279 – 28810Cytoplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane289 – 30820Helical; Name=9
Topological domain309 – 3113Periplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane312 – 33423Helical; Name=10
Topological domain335 – 34612Cytoplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane347 – 37428Helical; Name=11
Topological domain375 – 3773Periplasmic Ref.6 Ref.7 Ref.8 Ref.13
Transmembrane378 – 39821Helical; Name=12
Topological domain399 – 41719Cytoplasmic Ref.6 Ref.7 Ref.8 Ref.13

Sites

Site1261Substrate binding
Site1441Substrate binding
Site2691Substrate binding and proton translocation
Site3021Proton translocation
Site3221Proton translocation
Site3251Proton translocation

Amino acid modifications

Modified residue11N-formylmethionine; partial

Experimental info

Mutagenesis2371D → N or G: Defect in melibiose transport.
Mutagenesis3581K → T: Defect in melibiose transport.

Secondary structure

.................................................................... 417
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
P02920 [UniParc].

Last modified July 21, 1986. Version 1.
Checksum: 24A8062F628CDA32

FASTA41746,503
        10         20         30         40         50         60 
MYYLKNTNFW MFGLFFFFYF FIMGAYFPFF PIWLHDINHI SKSDTGIIFA AISLFSLLFQ 

        70         80         90        100        110        120 
PLFGLLSDKL GLRKYLLWII TGMLVMFAPF FIFIFGPLLQ YNILVGSIVG GIYLGFCFNA 

       130        140        150        160        170        180 
GAPAVEAFIE KVSRRSNFEF GRARMFGCVG WALCASIVGI MFTINNQFVF WLGSGCALIL 

       190        200        210        220        230        240 
AVLLFFAKTD APSSATVANA VGANHSAFSL KLALELFRQP KLWFLSLYVI GVSCTYDVFD 

       250        260        270        280        290        300 
QQFANFFTSF FATGEQGTRV FGYVTTMGEL LNASIMFFAP LIINRIGGKN ALLLAGTIMS 

       310        320        330        340        350        360 
VRIIGSSFAT SALEVVILKT LHMFEVPFLL VGCFKYITSQ FEVRFSATIY LVCFCFFKQL 

       370        380        390        400        410 
AMIFMSVLAG NMYESIGFQG AYLVLGLVAL GFTLISVFTL SGPGPLSLLR RQVNEVA 

« Hide

References

« Hide 'large scale' references
[1]"Sequence of the lactose permease gene."
Buechel D.E., Gronenborn B., Mueller-Hill B.
Nature 283:541-545(1980) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]Pastore J.C., Larigan J.D., Consler T.G., Kaback H.R.
Submitted (SEP-1990) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
Strain: K12.
[3]"Sequence of minutes 4-25 of Escherichia coli."
Chung E., Allen E., Araujo R., Aparicio A.M., Davis K., Duncan M., Federspiel N., Hyman R., Kalman S., Komp C., Kurdi O., Lew H., Lin D., Namath A., Oefner P., Roberts D., Schramm S., Davis R.W.
Submitted (JAN-1997) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: K12 / MG1655 / ATCC 47076.
[4]"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 277:1453-1462(1997) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: K12 / MG1655 / ATCC 47076.
[5]"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] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[6]"The distribution of positively charged residues in bacterial inner membrane proteins correlates with the trans-membrane topology."
von Heijne G.
EMBO J. 5:3021-3027(1986) [PubMed] [Europe PMC] [Abstract]
Cited for: TOPOLOGY.
[7]"lac permease of Escherichia coli: topology and sequence elements promoting membrane insertion."
Calamia J., Manoil C.
Proc. Natl. Acad. Sci. U.S.A. 87:4937-4941(1990) [PubMed] [Europe PMC] [Abstract]
Cited for: TOPOLOGY.
[8]"Membrane topology of helices VII and XI in the lactose permease of Escherichia coli studied by lacY-phoA fusion analysis and site-directed spectroscopy."
Ujwal M.L., Jung H., Bibi E., Manoil C., Altenbach C., Hubbell W.L., Kaback H.R.
Biochemistry 34:14909-14917(1995) [PubMed] [Europe PMC] [Abstract]
Cited for: TOPOLOGY.
[9]"The interaction between aspartic acid 237 and lysine 358 in the lactose carrier of Escherichia coli."
King S.C., Hansen C.L., Wilson T.H.
Biochim. Biophys. Acta 1062:177-186(1991) [PubMed] [Europe PMC] [Abstract]
Cited for: MUTAGENESIS.
[10]"Amino acid substitution in the lactose carrier protein with the use of amber suppressors."
Huang A.-M., Lee J.-I., King S.C., Wilson T.H.
J. Bacteriol. 174:5436-5441(1992) [PubMed] [Europe PMC] [Abstract]
Cited for: MUTAGENESIS.
[11]"The lac permease of Escherichia coli: a prototypic energy-transducing membrane protein."
Kaback H.R.
Biochim. Biophys. Acta 1018:160-162(1990) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW.
[12]"Toward the bilayer proteome, electrospray ionization-mass spectrometry of large, intact transmembrane proteins."
Whitelegge J.P., le Coutre J., Lee J.C., Engel C.K., Prive G.G., Faull K.F., Kaback H.R.
Proc. Natl. Acad. Sci. U.S.A. 96:10695-10698(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: MASS SPECTROMETRY OF FORMYLATED FORM.
[13]"Global topology analysis of the Escherichia coli inner membrane proteome."
Daley D.O., Rapp M., Granseth E., Melen K., Drew D., von Heijne G.
Science 308:1321-1323(2005) [PubMed] [Europe PMC] [Abstract]
Cited for: TOPOLOGY [LARGE SCALE ANALYSIS].
Strain: K12 / MG1655 / ATCC 47076.
[14]"Structure and mechanism of the lactose permease of Escherichia coli."
Abramson J., Smirnova I., Kasho V., Verner G., Kaback H.R., Iwata S.
Science 301:610-615(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (3.5 ANGSTROMS) OF MUTANT GLY-154.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
J01636 Genomic DNA. Translation: AAA24054.1.
V00295 Genomic DNA. Translation: CAA23571.1.
X56095 Genomic DNA. Translation: CAA39575.1.
U73857 Genomic DNA. Translation: AAB18067.1.
U00096 Genomic DNA. Translation: AAC73446.1.
AP009048 Genomic DNA. Translation: BAE76125.1.
PIRGREC. A03418.
RefSeqNP_414877.1. NC_000913.3.
YP_488637.1. NC_007779.1.

3D structure databases

PDBe
RCSB PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1M2Umodel-A1-417[»]
1PV6X-ray3.50A/B1-417[»]
1PV7X-ray3.60A/B1-417[»]
2CFPX-ray3.30A1-417[»]
2CFQX-ray2.95A1-417[»]
2V8NX-ray3.60A/B1-417[»]
2Y5YX-ray3.38A/B1-417[»]
ProteinModelPortalP02920.
SMRP02920. Positions 1-417.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

DIPDIP-10080N.
STRING511145.b0343.

Protein family/group databases

TCDB2.A.1.5.1. the major facilitator superfamily (mfs).

Proteomic databases

PRIDEP02920.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblBacteriaAAC73446; AAC73446; b0343.
BAE76125; BAE76125; BAE76125.
GeneID12934191.
949083.
KEGGecj:Y75_p0332.
eco:b0343.
PATRIC32115819. VBIEscCol129921_0351.

Organism-specific databases

EchoBASEEB0521.
EcoGeneEG10526. lacY.

Phylogenomic databases

eggNOGCOG0477.
HOGENOMHOG000114363.
KOK02532.
OMAPFLIVGC.
OrthoDBEOG6KHG2V.
PhylomeDBP02920.
ProtClustDBPRK09528.

Enzyme and pathway databases

BioCycEcoCyc:LACY-MONOMER.
ECOL316407:JW0334-MONOMER.

Gene expression databases

GenevestigatorP02920.

Family and domain databases

InterProIPR000576. LacY/RafB_perm_fam.
IPR018457. LacY/RafB_perm_fam_CS.
IPR020846. MFS_dom.
IPR016196. MFS_dom_general_subst_transpt.
[Graphical view]
PfamPF01306. LacY_symp. 1 hit.
[Graphical view]
PRINTSPR00174. LACYSMPORT.
SUPFAMSSF103473. SSF103473. 1 hit.
TIGRFAMsTIGR00882. 2A0105. 1 hit.
PROSITEPS00896. LACY_1. 1 hit.
PS00897. LACY_2. 1 hit.
PS50850. MFS. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceP02920.
PROP02920.

Entry information

Entry nameLACY_ECOLI
AccessionPrimary (citable) accession number: P02920
Secondary accession number(s): Q2MC81
Entry history
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 21, 1986
Last modified: April 16, 2014
This is version 139 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references

Escherichia coli

Escherichia coli (strain K12): entries and cross-references to EcoGene