RegulonDB

Gene
Name:	melB
Synonym(s):	ECK4113, EG10578, b4120, mel-4
Genome position(nucleotides):	4343369 --> 4344790
Strand:	forward
Sequence:	Get nucleotide sequence FastaFormat
GC content %:	45.85
External database links:

ASAP:	ABE-0013495
CGSC:	521
ECHOBASE:	EB0573
ECOLIHUB:	melB
OU-MICROARRAY:	b4120
STRING:	511145.b4120
COLOMBOS:	melB

Product

Name:

melibiose:H⁺/Na⁺/Li⁺ symporter

Synonym(s):

MelB, MelB GPH transporter

Sequence:

Get amino acid sequence Fasta Format

Cellular location:

inner membrane

Molecular weight:

52.636

Isoelectric point:

8.682

Motif(s):

Type	Positions	Sequence	Comment
	2 -> 473	SISMTTKLSYGFGAFGKDFAIGIVYMYLMYYYTDVVGLSVGLVGTLFLVARIWDAINDPIMGWIVNATRSRWGKFKPWILIGTLANSVILFLLFSAHLFEGTTQIVFVCVTYILWGMTYTIMDIPFWSLVPTITLDKREREQLVPYPRFFASLAGFVTAGVTLPFVNYVGGGDRGFGFQMFTLVLIAFFIVSTIITLRNVHEVFSSDNQPSAEGSHLTLKAIVALIYKNDQLSCLLGMALAYNVASNIITGFAIYYFSYVIGDADLFPYYLSYAGAANLVTLVFFPRLVKSLSRRILWAGASILPVLSCGVLLLMALMSYHNVVLIVIAGILLNVGTALFWVLQVIMVADIVDYGEYKLHVRCESIAYSVQTMVVKGGSAFAAFFIAVVLGMIGYVPNVEQSTQALLGMQFIMIALPTLFFMVTLILYFRFYRLNGDTLRRIQIHLLDKYRKVPPEPVHADIPVGAVSDVKA	UniProt: Melibiose carrier protein.
	10 -> 436	SYGFGAFGKDFAIGIVYMYLMYYYTDVVGLSVGLVGTLFLVARIWDAINDPIMGWIVNATRSRWGKFKPWILIGTLANSVILFLLFSAHLFEGTTQIVFVCVTYILWGMTYTIMDIPFWSLVPTITLDKREREQLVPYPRFFASLAGFVTAGVTLPFVNYVGGGDRGFGFQMFTLVLIAFFIVSTIITLRNVHEVFSSDNQPSAEGSHLTLKAIVALIYKNDQLSCLLGMALAYNVASNIITGFAIYYFSYVIGDADLFPYYLSYAGAANLVTLVFFPRLVKSLSRRILWAGASILPVLSCGVLLLMALMSYHNVVLIVIAGILLNVGTALFWVLQVIMVADIVDYGEYKLHVRCESIAYSVQTMVVKGGSAFAAFFIAVVLGMIGYVPNVEQSTQALLGMQFIMIALPTLFFMVTLILYFRFYRLN
	20 -> 40	FAIGIVYMYLMYYYTDVVGLS	UniProt: Helical.
	43 -> 63	LVGTLFLVARIWDAINDPIMG	UniProt: Helical.
	59 -> 59	D	UniProt: Loses ability to catalyze Na(+) or H(+)-coupled melibiose transport against a concentration gradient..

Classification:

Multifun Terms (GenProtEC)
		1 - metabolism --> 1.1 - carbon utilization --> 1.1.1 - carbon compounds
		4 - transport --> 4.2 - Electrochemical potential driven transporters --> 4.2.A - Porters (Uni-, Sym- and Antiporters)
		6 - cell structure --> 6.1 - membrane
Gene Ontology Terms (GO)
	cellular_component	GO:0016020 - membrane GO:0005886 - plasma membrane GO:0005887 - integral component of plasma membrane GO:0016021 - integral component of membrane
	molecular_function	GO:0005515 - protein binding GO:0015293 - symporter activity GO:0022857 - transmembrane transporter activity GO:0015486 - glycoside-pentoside-hexuronide:cation symporter activity GO:0015487 - melibiose:cation symporter activity GO:0015592 - methylgalactoside transmembrane transporter activity GO:0043887 - melibiose:sodium symporter activity
	biological_process	GO:0008643 - carbohydrate transport GO:0006814 - sodium ion transport GO:0055085 - transmembrane transport GO:0034219 - carbohydrate transmembrane transport GO:0071702 - organic substance transport GO:0035725 - sodium ion transmembrane transport GO:0015765 - methylgalactoside transport GO:0015769 - melibiose transport

Note(s):

Note(s): ...[more].

Reference(s):

[1] Abdel-Dayem M., et al., 2003
[2] Ganea C., et al., 2009
[3] Ganea C., et al., 2001
[4] Garcia-Celma JJ., et al., 2008
[5] Granell M., et al., 2010
[6] Leon X., et al., 2005
[7] Meyer-Lipp K., et al., 2004
[8] Meyer-Lipp K., et al., 2006
[9] Pourcher T., et al., 1991
[10] Pourcher T., et al., 1995
[11] Pourcher T., et al., 1993
[12] Purhonen P., et al., 2005
[13] Tsuchiya T., et al., 1985
[14] Yousef MS., et al., 2009
[15] Zani ML., et al., 1994
[16] Zani ML., et al., 1993

External database links:

ALPHAFOLD:

DIP:

ECOCYC:

ECOLIWIKI:

INTERPRO:

INTERPRO:

INTERPRO:

INTERPRO:

PANTHER:

PFAM:

PRIDE:

PRODB:

PROSITE:

REFSEQ:

UNIPROT:

Transcriptional Regulation
	Display Regulation
Activated by:	MelR, CRP
Repressed by:	MelR

Reference(s)
[1] Abdel-Dayem M., Basquin C., Pourcher T., Cordat E., Leblanc G., 2003, Cytoplasmic loop connecting helices IV and V of the melibiose permease from Escherichia coli is involved in the process of Na+-coupled sugar translocation., J Biol Chem 278(3):1518-24
[2] Ganea C., Fendler K., 2009, Bacterial transporters: Charge translocation and mechanism., Biochim Biophys Acta 1787(6):706-13
[3] Ganea C., Pourcher T., Leblanc G., Fendler K., 2001, Evidence for intraprotein charge transfer during the transport activity of the melibiose permease from Escherichia coli., Biochemistry 40(45):13744-52
[4] Garcia-Celma JJ., Dueck B., Stein M., Schlueter M., Meyer-Lipp K., Leblanc G., Fendler K., 2008, Rapid activation of the melibiose permease MelB immobilized on a solid-supported membrane., Langmuir 24(15):8119-26
[5] Granell M., Leon X., Leblanc G., Padros E., Lorenz-Fonfria VA., 2010, Structural insights into the activation mechanism of melibiose permease by sodium binding., Proc Natl Acad Sci U S A 107(51):22078-83
[6] Leon X., Lorenz-Fonfria VA., Lemonnier R., Leblanc G., Padros E., 2005, Substrate-induced conformational changes of melibiose permease from Escherichia coli studied by infrared difference spectroscopy., Biochemistry 44(9):3506-14
[7] Meyer-Lipp K., Ganea C., Pourcher T., Leblanc G., Fendler K., 2004, Sugar binding induced charge translocation in the melibiose permease from Escherichia coli., Biochemistry 43(39):12606-13
[8] Meyer-Lipp K., Sery N., Ganea C., Basquin C., Fendler K., Leblanc G., 2006, The inner interhelix loop 4-5 of the melibiose permease from Escherichia coli takes part in conformational changes after sugar binding., J Biol Chem 281(36):25882-92
[9] Pourcher T., Deckert M., Bassilana M., Leblanc G., 1991, Melibiose permease of Escherichia coli: mutation of aspartic acid 55 in putative helix II abolishes activation of sugar binding by Na+ ions., Biochem Biophys Res Commun 178(3):1176-81
[10] Pourcher T., Leclercq S., Brandolin G., Leblanc G., 1995, Melibiose permease of Escherichia coli: large scale purification and evidence that H+, Na+, and Li+ sugar symport is catalyzed by a single polypeptide., Biochemistry 34(13):4412-20
[11] Pourcher T., Zani ML., Leblanc G., 1993, Mutagenesis of acidic residues in putative membrane-spanning segments of the melibiose permease of Escherichia coli. I. Effect on Na(+)-dependent transport and binding properties., J Biol Chem 268(5):3209-15
[12] Purhonen P., Lundback AK., Lemonnier R., Leblanc G., Hebert H., 2005, Three-dimensional structure of the sugar symporter melibiose permease from cryo-electron microscopy., J Struct Biol 152(1):76-83
[13] Tsuchiya T., Wilson DM., Wilson TH., 1985, Melibiose-cation cotransport system of Escherichia coli., Ann N Y Acad Sci 456:342-9
[14] Yousef MS., Guan L., 2009, A 3D structure model of the melibiose permease of Escherichia coli represents a distinctive fold for Na+ symporters., Proc Natl Acad Sci U S A 106(36):15291-6
[15] Zani ML., Pourcher T., Leblanc G., 1994, Mutation of polar and charged residues in the hydrophobic NH2-terminal domains of the melibiose permease of Escherichia coli., J Biol Chem 269(40):24883-9
[16] Zani ML., Pourcher T., Leblanc G., 1993, Mutagenesis of acidic residues in putative membrane-spanning segments of the melibiose permease of Escherichia coli. II. Effect on cationic selectivity and coupling properties., J Biol Chem 268(5):3216-21

RNA cis-regulatory element

Attenuation:	Translational