melB

Functionⁱ

Responsible for melibiose and other galactoside transport. It is capable of using hydrogen, sodium, and lithium cations as coupling cations for cotransport, depending on the particular sugar transported (symport system).

GO - Molecular functionⁱ

melibiose:cation symporter activity
Source: EcoCyc
Inferred from direct assayⁱ
- 2185831
- 7703254
melibiose:sodium symporter activity
Source: EcoCyc
Inferred from direct assayⁱ
- 7703254
methylgalactoside transmembrane transporter activity
Source: EcoCyc
Inferred from direct assayⁱ
- 3311166

View the complete GO annotation on QuickGO ...

GO - Biological processⁱ

melibiose transport
Source: EcoCyc
Inferred from direct assayⁱ
- 6319412
methylgalactoside transport
Source: EcoCyc
Inferred from direct assayⁱ
- 3311166

View the complete GO annotation on QuickGO ...

Keywordsⁱ

Biological process	Sugar transport, Symport, Transport

Biological process

Sugar transport, Symport, Transport

Enzyme and pathway databases

BioCycⁱ	EcoCyc:MELB-MONOMER MetaCyc:MELB-MONOMER

BioCycⁱ

EcoCyc:MELB-MONOMER
MetaCyc:MELB-MONOMER

Names & Taxonomyⁱ

Protein namesⁱ	Recommended name: Melibiose carrier protein Alternative name(s): Melibiose permease Melibiose transporter Na+ (Li+)/melibiose symporter Thiomethylgalactoside permease II
Gene namesⁱ	Name:melB Synonyms:mel-4 Ordered Locus Names:b4120, JW4081
Organismⁱ	Escherichia coli (strain K12)
Taxonomic identifierⁱ	83333 [NCBI]
Taxonomic lineageⁱ	cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacterales › Enterobacteriaceae › Escherichia › Escherichia coli
Proteomesⁱ	UP000000318 Componentⁱ: Chromosome UP000000625 Componentⁱ: Chromosome

Organism-specific databases

EcoGeneⁱ	EG10578 melB

EcoGeneⁱ

EG10578 melB

Subcellular locationⁱ

Cell inner membrane
1 Publication
Manual assertion based on experiment inⁱ
- Ref.5
  "Melibiose permease of Escherichia coli: large scale purification and evidence that H+, Na+, and Li+ sugar symport is catalyzed by a single polypeptide."
  Pourcher T., Leclercq S., Brandolin G., Leblanc G.
  Biochemistry 34:4412-4420(1995) [PubMed] [Europe PMC] [Abstract]
  Cited for: PROTEIN SEQUENCE OF 2-8, CHARACTERIZATION, SUBCELLULAR LOCATION, SUBUNIT.
; Multi-pass membrane protein
1 Publication
Manual assertion based on experiment inⁱ
- Ref.5
  "Melibiose permease of Escherichia coli: large scale purification and evidence that H+, Na+, and Li+ sugar symport is catalyzed by a single polypeptide."
  Pourcher T., Leclercq S., Brandolin G., Leblanc G.
  Biochemistry 34:4412-4420(1995) [PubMed] [Europe PMC] [Abstract]
  Cited for: PROTEIN SEQUENCE OF 2-8, CHARACTERIZATION, SUBCELLULAR LOCATION, SUBUNIT.

Topology

Feature key	Position(s)	DescriptionActions	Length
Topological domainⁱ	5 – 19	CytoplasmicCuratedAdd BLAST	15
Transmembraneⁱ	20 – 40	HelicalCuratedAdd BLAST	21
Topological domainⁱ	41 – 42	PeriplasmicCurated	2
Transmembraneⁱ	43 – 63	HelicalCuratedAdd BLAST	21
Topological domainⁱ	64 – 80	CytoplasmicCuratedAdd BLAST	17
Transmembraneⁱ	81 – 101	HelicalCuratedAdd BLAST	21
Topological domainⁱ	102 – 108	PeriplasmicCurated	7
Transmembraneⁱ	109 – 129	HelicalCuratedAdd BLAST	21
Topological domainⁱ	130 – 153	CytoplasmicCuratedAdd BLAST	24
Transmembraneⁱ	154 – 174	HelicalCuratedAdd BLAST	21
Topological domainⁱ	175 – 186	PeriplasmicCuratedAdd BLAST	12
Transmembraneⁱ	187 – 207	HelicalCuratedAdd BLAST	21
Topological domainⁱ	208 – 235	CytoplasmicCuratedAdd BLAST	28
Transmembraneⁱ	236 – 256	HelicalCuratedAdd BLAST	21
Topological domainⁱ	257 – 269	PeriplasmicCuratedAdd BLAST	13
Transmembraneⁱ	270 – 290	HelicalCuratedAdd BLAST	21
Topological domainⁱ	291 – 299	CytoplasmicCurated	9
Transmembraneⁱ	300 – 320	HelicalCuratedAdd BLAST	21
Topological domainⁱ	321 – 328	PeriplasmicCurated	8
Transmembraneⁱ	329 – 349	HelicalCuratedAdd BLAST	21
Topological domainⁱ	350 – 381	CytoplasmicCuratedAdd BLAST	32
Transmembraneⁱ	382 – 402	HelicalCuratedAdd BLAST	21
Topological domainⁱ	403 – 410	PeriplasmicCurated	8
Transmembraneⁱ	411 – 431	HelicalCuratedAdd BLAST	21
Topological domainⁱ	432 – 473	CytoplasmicCuratedAdd BLAST	42

GO - Cellular componentⁱ

integral component of plasma membrane
Source: EcoCyc
Inferred from direct assayⁱ
- 2185831
plasma membrane
Source: EcoCyc
Inferred from direct assayⁱ
- 15919996

View the complete GO annotation on QuickGO ...

Keywords - Cellular componentⁱ

Cell inner membrane, Cell membrane, Membrane

Pathology & Biotechⁱ

Mutagenesis

Feature key	Position(s)	DescriptionActions	Graphical view	Length
Mutagenesisⁱ	59	D → C: Loses ability to catalyze Na(+) or H(+)-coupled melibiose transport against a concentration gradient. 1 Publication		1

PTM / Processingⁱ

Molecule processing

Feature key	Position(s)	DescriptionActions	Graphical view	Length
Initiator methionineⁱ		Removed1 Publication
ChainⁱPRO_0000170752	2 – 473	Melibiose carrier proteinAdd BLAST		472

Proteomic databases

PaxDbⁱ	P02921
PRIDEⁱ	P02921

Interactionⁱ

Subunit structureⁱ

Monomer and homodimer.1 Publication

Protein-protein interaction databases

BioGridⁱ	4263176, 14 interactors
Database of interacting proteins More...DIPⁱ	DIP-10180N
IntActⁱ	P02921, 1 interactor
STRINGⁱ	316385.ECDH10B_4312

Structureⁱ

3D structure databases

ProteinModelPortalⁱ	P02921
ModBaseⁱ	Search...
MobiDBⁱ	Search...

Family & Domainsⁱ

Sequence similaritiesⁱ

Belongs to the sodium:galactoside symporter (TC 2.A.2) family. [View classification]Curated

Keywords - Domainⁱ

Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGⁱ	ENOG4105CT4 Bacteria COG2211 LUCA
HOGENOMⁱ	HOG000294602
InParanoidⁱ	P02921
KEGG Orthology (KO) More...KOⁱ	K11104

Family and domain databases

InterProⁱ	View protein in InterPro IPR036259 MFS_trans_sf IPR001927 Na/Gal_symport IPR018043 Na/Gal_symport_CS
SUPFAMⁱ	SSF103473 SSF103473, 1 hit
TIGRFAMsⁱ	TIGR00792 gph, 1 hit
PROSITEⁱ	View protein in PROSITE PS00872 NA_GALACTOSIDE_SYMP, 1 hit

Sequenceⁱ

Sequence statusⁱ: Complete.

Sequence processingⁱ: The displayed sequence is further processed into a mature form.

P02921-1 [UniParc]FASTA Add to basket

« Hide

        10         20         30         40         50
MSISMTTKLS YGFGAFGKDF AIGIVYMYLM YYYTDVVGLS VGLVGTLFLV 
        60         70         80         90        100
ARIWDAINDP IMGWIVNATR SRWGKFKPWI LIGTLANSVI LFLLFSAHLF 
       110        120        130        140        150
EGTTQIVFVC VTYILWGMTY TIMDIPFWSL VPTITLDKRE REQLVPYPRF 
       160        170        180        190        200
FASLAGFVTA GVTLPFVNYV GGGDRGFGFQ MFTLVLIAFF IVSTIITLRN 
       210        220        230        240        250
VHEVFSSDNQ PSAEGSHLTL KAIVALIYKN DQLSCLLGMA LAYNVASNII 
       260        270        280        290        300
TGFAIYYFSY VIGDADLFPY YLSYAGAANL VTLVFFPRLV KSLSRRILWA 
       310        320        330        340        350
GASILPVLSC GVLLLMALMS YHNVVLIVIA GILLNVGTAL FWVLQVIMVA 
       360        370        380        390        400
DIVDYGEYKL HVRCESIAYS VQTMVVKGGS AFAAFFIAVV LGMIGYVPNV 
       410        420        430        440        450
EQSTQALLGM QFIMIALPTL FFMVTLILYF RFYRLNGDTL RRIQIHLLDK 
       460        470 
YRKVPPEPVH ADIPVGAVSD VKA

Length:473

Mass (Da):52,636

Last modified:October 19, 2011 - v2

Checksum:ⁱE05FAA436F4CA70C

GO

Sequence cautionⁱ

The sequence AAA24148 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated

The sequence AAA97020 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated

The sequence BAE78122 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated

Sequence databases

Select the link destinations: EMBLⁱ GenBankⁱ DDBJⁱ Links Updated	K01991 Genomic DNA Translation: AAA24148.1 Different initiation. U14003 Genomic DNA Translation: AAA97020.1 Different initiation. U00096 Genomic DNA Translation: AAC77081.2 AP009048 Genomic DNA Translation: BAE78122.1 Different initiation.
PIRⁱ	A03421 BDEC
NCBI Reference Sequences More...RefSeqⁱ	NP_418544.2, NC_000913.3 WP_000028111.1, NZ_LN832404.1

Genome annotation databases

EnsemblBacteriaⁱ	AAC77081; AAC77081; b4120 BAE78122; BAE78122; BAE78122
GeneIDⁱ	948635
KEGGⁱ	ecj:JW4081 eco:b4120
PATRICⁱ	fig\|511145.12.peg.4251

Protein	Similar proteins		Species	Score	Length	Source
P02921	Melibiose carrier protein		Escherichia coli 2.3916		481	UniRef100_P02921
Melibiose carrier protein		ECOLX		473
Melibiose carrier protein		SHISO		473
Melibiose carrier protein		Escherichia coli H386		473
Melibiose carrier protein (Thiomethylgalactoside permease II)(Melibiose permease) (Na+ (Li+)/melibiose symporter) (Melibiosetransporter)		Escherichia coli H736		473
+10

Protein	Similar proteins		Species	Score	Length	Source
P02921	Melibiose carrier protein		Escherichia coli 2.3916		481	UniRef90_P02921
Melibiose carrier protein		ECOLX		473
Melibiose carrier protein		SHISO		473
Melibiose carrier protein		Escherichia coli H386		473
Melibiose carrier protein (Thiomethylgalactoside permease II)(Melibiose permease) (Na+ (Li+)/melibiose symporter) (Melibiosetransporter)		Escherichia coli H736		473
+560

Protein	Similar proteins		Species	Score	Length	Source
P02921	Melibiose carrier protein		KLEPN		471	UniRef50_P02921
Melibiose carrier protein		KLEAE		471
Melibiose carrier protein	)	SALTY		476
Melibiose carrier protein		Escherichia coli 2.3916		481
Melibiose carrier protein		ECOLX		473
+1490

Cross-referencesⁱ

Sequence databases

Select the link destinations: EMBLⁱ GenBankⁱ DDBJⁱ Links Updated	K01991 Genomic DNA Translation: AAA24148.1 Different initiation. U14003 Genomic DNA Translation: AAA97020.1 Different initiation. U00096 Genomic DNA Translation: AAC77081.2 AP009048 Genomic DNA Translation: BAE78122.1 Different initiation.
PIRⁱ	A03421 BDEC
RefSeqⁱ	NP_418544.2, NC_000913.3 WP_000028111.1, NZ_LN832404.1

3D structure databases

ProteinModelPortalⁱ	P02921
ModBaseⁱ	Search...
MobiDBⁱ	Search...

Protein-protein interaction databases

BioGridⁱ	4263176, 14 interactors
DIPⁱ	DIP-10180N
IntActⁱ	P02921, 1 interactor
STRINGⁱ	316385.ECDH10B_4312

Proteomic databases

PaxDbⁱ	P02921
PRIDEⁱ	P02921

Protocols and materials databases

Structural Biology Knowledgebase	Search...

Structural Biology Knowledgebase

Search...

Genome annotation databases

EnsemblBacteriaⁱ	AAC77081; AAC77081; b4120 BAE78122; BAE78122; BAE78122
GeneIDⁱ	948635
KEGGⁱ	ecj:JW4081 eco:b4120
PATRICⁱ	fig\|511145.12.peg.4251

Organism-specific databases

EchoBASEⁱ	EB0573
EcoGeneⁱ	EG10578 melB

Phylogenomic databases

eggNOGⁱ	ENOG4105CT4 Bacteria COG2211 LUCA
HOGENOMⁱ	HOG000294602
InParanoidⁱ	P02921
KOⁱ	K11104

Enzyme and pathway databases

BioCycⁱ	EcoCyc:MELB-MONOMER MetaCyc:MELB-MONOMER

BioCycⁱ

EcoCyc:MELB-MONOMER
MetaCyc:MELB-MONOMER

Miscellaneous databases

Protein Ontology More...PROⁱ	PR:P02921

PROⁱ

PR:P02921

Family and domain databases

InterProⁱ	View protein in InterPro IPR036259 MFS_trans_sf IPR001927 Na/Gal_symport IPR018043 Na/Gal_symport_CS
SUPFAMⁱ	SSF103473 SSF103473, 1 hit
TIGRFAMsⁱ	TIGR00792 gph, 1 hit
PROSITEⁱ	View protein in PROSITE PS00872 NA_GALACTOSIDE_SYMP, 1 hit
ProtoNetⁱ	Search...

Entry informationⁱ

Entry nameⁱ	MELB_ECOLI
Accessionⁱ	P02921Primary (citable) accession number: P02921 Secondary accession number(s): Q2M6I4
Entry historyⁱ	Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
	Last sequence update:	October 19, 2011
	Last modified:	April 25, 2018
	This is version 148 of the entry and version 2 of the sequence. See complete history.
Entry statusⁱ	Reviewed (UniProtKB/Swiss-Prot)
Annotation program	Prokaryotic Protein Annotation Program

Miscellaneousⁱ

Keywords - Technical termⁱ

Complete proteome, Direct protein sequencing, Reference proteome

Documents

SIMILARITY comments
Index of protein domains and families
Escherichia coli
Escherichia coli (strain K12): entries and cross-references to EcoGene

UniProtKB

UniParc

Help

UniRef

Proteomes

Annotation systems

Supporting data

UniProtKB - P02921 (MELB_ECOLI)

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Melibiose carrier protein

Select a section on the left to see content.

<p>This section provides any useful information about the protein, mostly biological knowledge.<p><a href='/help/function_section' target='_top'>More...</a></p>Functioni

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:<p><a href='/help/gene_ontology' target='_top'>More...</a></p>GO - Molecular functioni

GO - Biological processi

Enzyme and pathway databases

<p>This section provides information about the protein and gene name(s) and synonym(s) and about the organism that is the source of the protein sequence.<p><a href='/help/names_and_taxonomy_section' target='_top'>More...</a></p>Names & Taxonomyi

Organism-specific databases

<p>This section provides information on the location and the topology of the mature protein in the cell.<p><a href='/help/subcellular_location_section' target='_top'>More...</a></p>Subcellular locationi

Topology

GO - Cellular componenti

Keywords - Cellular componenti

<p>This section provides information on the disease(s) and phenotype(s) associated with a protein.<p><a href='/help/pathology_and_biotech_section' target='_top'>More...</a></p>Pathology & Biotechi

Mutagenesis

<p>This section describes post-translational modifications (PTMs) and/or processing events.<p><a href='/help/ptm_processing_section' target='_top'>More...</a></p>PTM / Processingi

Molecule processing

Proteomic databases

<p>This section provides information on the quaternary structure of a protein and on interaction(s) with other proteins or protein complexes.<p><a href='/help/interaction_section' target='_top'>More...</a></p>Interactioni

Protein-protein interaction databases

<p>This section provides information on the tertiary and secondary structure of a protein.<p><a href='/help/structure_section' target='_top'>More...</a></p>Structurei

3D structure databases

<p>This section provides information on sequence similarities with other proteins and the domain(s) present in a protein.<p><a href='/help/family_and_domains_section' target='_top'>More...</a></p>Family & Domainsi

<p>This subsection of the ‘Family and domains’ section provides information about the sequence similarity with other proteins.<p><a href='/help/sequence_similarities' target='_top'>More...</a></p>Sequence similaritiesi

Keywords - Domaini

Phylogenomic databases

Family and domain databases

<p>This subsection of the ‘Sequence’ section reports difference(s) between the protein sequence shown in the UniProtKB entry and other available protein sequences derived from the same gene.<p><a href='/help/sequence_caution' target='_top'>More...</a></p>Sequence cautioni

Sequence databases

Genome annotation databases

<p>This section is used to point to information related to entries and found in data collections other than UniProtKB.<p><a href='/help/cross_references_section' target='_top'>More...</a></p>Cross-referencesi

Sequence databases

3D structure databases

Protein-protein interaction databases

Proteomic databases

Protocols and materials databases

Genome annotation databases

Organism-specific databases

Phylogenomic databases

Enzyme and pathway databases

Miscellaneous databases

Family and domain databases

<p>This section provides general information on the entry.<p><a href='/help/entry_information_section' target='_top'>More...</a></p>Entry informationi

<p>This section contains any relevant information that doesn’t fit in any other defined sections<p><a href='/help/miscellaneous_section' target='_top'>More...</a></p>Miscellaneousi

Keywords - Technical termi

Documents

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Functionⁱ

GO - Molecular functionⁱ

GO - Biological processⁱ

Names & Taxonomyⁱ

Subcellular locationⁱ

GO - Cellular componentⁱ

Keywords - Cellular componentⁱ

Pathology & Biotechⁱ

PTM / Processingⁱ

Interactionⁱ

Structureⁱ

Family & Domainsⁱ

Sequence similaritiesⁱ

Keywords - Domainⁱ

Sequence cautionⁱ

Cross-referencesⁱ

Entry informationⁱ

Miscellaneousⁱ

Keywords - Technical termⁱ