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1.B.3.1.1
LamB (MalL) maltoporin (maltose–maltoheptose).  Also catalyzes the uptake of antibiotics (Lin et al. 2014).

Accession Number:P02943
Protein Name:LamB aka MALB aka B4036
Length:446
Molecular Weight:49912.00
Species:Escherichia coli [83333]
Number of TMSs:1
Location1 / Topology2 / Orientation3: Cell outer membrane1 / Multi-pass membrane protein2
Substrate Maltose, Maltobiose, Maltotriose, Maltotetrose, Maltopentose, Maltohexose, Maltoheptose, antibiotics

Cross database links:

Genevestigator: P02943
EchoBASE: EB0523
EcoGene: EG10528
eggNOG: COG4580
HEGENOM: HBG309714
DIP: DIP-10082N
RefSeq: AP_004537.1    NP_418460.1   
Entrez Gene ID: 948548   
Pfam: PF02264   
Drugbank: Drugbank Link   
BioCyc: EcoCyc:EG10528-MONOMER    ECOL168927:B4036-MONOMER   
KEGG: ecj:JW3996    eco:b4036   

Gene Ontology

GO:0009279 C:cell outer membrane
GO:0005886 C:plasma membrane
GO:0046930 C:pore complex
GO:0015288 F:porin activity
GO:0005515 F:protein binding
GO:0005351 F:sugar:hydrogen symporter activity
GO:0009597 P:detection of virus
GO:0046718 P:entry of virus into host cell
GO:0006811 P:ion transport
GO:0015768 P:maltose transport

References (16)

[1] “Gene sequence of the lambda receptor, an outer membrane protein of E. coli K12.”  Clement J.M.et.al.   6086106
[2] “Analysis of the Escherichia coli genome. IV. DNA sequence of the region from 89.2 to 92.8 minutes.”  Blattner F.R.et.al.   8265357
[3] “The complete genome sequence of Escherichia coli K-12.”  Blattner F.R.et.al.   9278503
[4] “Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 and W3110.”  Hayashi K.et.al.   16738553
[5] “Sequence determinants in the lamB gene of Escherichia coli influencing the binding and pore selectivity of maltoporin.”  Heine H.G.et.al.   3301537
[6] “DNA sequence encoding the signal peptide of the lambda receptor in E. coli K 12.”  Clement J.M.et.al.   161974
[7] “DNA sequence encoding the NH2-terminal peptide involved in transport of lambda receptor, an Escherichia coli secretory protein.”  Hedgpeth J.et.al.   6446717
[8] “Genetic analysis of sequences in maltoporin that contribute to binding domains and pore structure.”  Heine H.G.et.al.   2832377
[9] “Role of a disulfide bond in the thermal stability of the LamB protein trimer in Escherichia coli outer membrane.”  Luckey M.et.al.   1988451
[10] “Permissive sites and topology of an outer membrane protein with a reporter epitope.”  Charbit A.et.al.   1702781
[11] “A model of maltodextrin transport through the sugar-specific porin, LamB, based on deletion analysis.”  Klebba P.E.et.al.   7925308
[12] “Sucrose transport through maltoporin mutants of Escherichia coli.”  Van Gelder P.et.al.   11742115
[13] “Protein complexes of the Escherichia coli cell envelope.”  Stenberg F.et.al.   16079137
[14] “Structural basis for sugar translocation through maltoporin channels at 3.1-A resolution.”  Schirmer T.et.al.   7824948
[15] “Crystal structures of various maltooligosaccharides bound to maltoporin reveal a specific sugar translocation pathway.”  Dutzler R.et.al.   8805519
[16] “Channel specificity: structural basis for sugar discrimination and differential flux rates in maltoporin.”  Wang Y.-F.et.al.   9299337
Structure:
1AF6   1MAL   1MPM   1MPN   1MPO   1MPQ     

External Searches:

  • Search: DB with
  • BLAST ExPASy (Swiss Institute of Bioinformatics (SIB) BLAST)
  • CDD Search (Conserved Domain Database)
  • Search COGs (Clusters of Orthologous Groups of proteins)
  • 2° Structure (Network Protein Sequence Analysis)

Analyze:

Predict TMSs (Predict number of transmembrane segments)
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FASTA formatted sequence
1:	MMITLRKLPL AVAVAAGVMS AQAMAVDFHG YARSGIGWTG SGGEQQCFQT TGAQSKYRLG 
61:	NECETYAELK LGQEVWKEGD KSFYFDTNVA YSVAQQNDWE ATDPAFREAN VQGKNLIEWL 
121:	PGSTIWAGKR FYQRHDVHMI DFYYWDISGP GAGLENIDVG FGKLSLAATR SSEAGGSSSF 
181:	ASNNIYDYTN ETANDVFDVR LAQMEINPGG TLELGVDYGR ANLRDNYRLV DGASKDGWLF 
241:	TAEHTQSVLK GFNKFVVQYA TDSMTSQGKG LSQGSGVAFD NEKFAYNINN NGHMLRILDH 
301:	GAISMGDNWD MMYVGMYQDI NWDNDNGTKW WTVGIRPMYK WTPIMSTVME IGYDNVESQR 
361:	TGDKNNQYKI TLAQQWQAGD SIWSRPAIRV FATYAKWDEK WGYDYTGNAD NNANFGKAVP 
421:	ADFNGGSFGR GDSDEWTFGA QMEIWW