UniProtKB - P69681 (AMTB_ECOLI)
Ammonium transporter AmtB
amtB
Functioni
Involved in the uptake of ammonium/ammonia (NH4+/NH3) (PubMed:14668330, PubMed:15876187, PubMed:15563598, PubMed:15361618, PubMed:16910683, PubMed:30211659, PubMed:32662768).
Transport is electrogenic (PubMed:30211659, PubMed:32662768).
Following sequestration of NH4+ at the periplasmic face, NH4+ is deprotonated and neutral NH3 is transported into the cytoplasm (PubMed:15876187, PubMed:16910683, PubMed:18362341, PubMed:19278252, PubMed:32662768).
Neutral NH3 and charged H+ are carried separately across the membrane on a unique two-lane pathway, before recombining to NH4+ inside the cell (PubMed:32662768).
In vitro can also transport the larger analogs methylamine and methylammonium (PubMed:11847102, PubMed:14668330, PubMed:12023896, PubMed:15876187, PubMed:17998534, PubMed:18362341).
Also acts as a sensor of the extracellular ammonium concentration (PubMed:14668330).
12 PublicationsMiscellaneous
Caution
Activity regulationi
Sites
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Sitei | 182 | Important for the deprotonation of the ammonium cation1 Publication | 1 | |
Sitei | 190 | Twin-His motif. Important for optimum substrate conductance3 Publications | 1 | |
Sitei | 237 | Important for optimum substrate conductance1 Publication | 1 | |
Binding sitei | 241 | Ammonium1 Publication | 1 | |
Sitei | 340 | Twin-His motif. Important for optimum substrate conductance3 Publications | 1 |
GO - Molecular functioni
- ammonium transmembrane transporter activity Source: UniProtKB
- identical protein binding Source: IntAct
- uniporter activity Source: EcoCyc
GO - Biological processi
- ammonium transport Source: UniProtKB
- carbon dioxide transport Source: UniProtKB
- nitrogen utilization Source: GO_Central
Keywordsi
Biological process | Ammonia transport, Transport |
Enzyme and pathway databases
BioCyci | EcoCyc:AMTB-MONOMER |
Protein family/group databases
TCDBi | 1.A.11.1.1, the ammonium transporter channel (amt) family |
Names & Taxonomyi
Protein namesi | Recommended name: Ammonium transporter AmtB2 PublicationsAlternative name(s): Ammonia channel AmtB2 Publications Ammonium channel AmtB1 Publication |
Gene namesi | Name:amtB1 Publication Synonyms:ybaG Ordered Locus Names:b0451, JW0441 |
Organismi | Escherichia coli (strain K12) |
Taxonomic identifieri | 83333 [NCBI] |
Taxonomic lineagei | Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacterales › Enterobacteriaceae › Escherichia › |
Proteomesi |
|
Subcellular locationi
Plasma membrane
- Cell inner membrane 5 Publications; Multi-pass membrane protein 3 Publications
Plasma Membrane
- integral component of plasma membrane Source: EcoCyc
- plasma membrane Source: EcoCyc
Topology
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Topological domaini | 23 – 32 | Periplasmic3 Publications | 10 | |
Transmembranei | 33 – 54 | Helical3 PublicationsAdd BLAST | 22 | |
Topological domaini | 55 – 65 | Cytoplasmic3 PublicationsAdd BLAST | 11 | |
Transmembranei | 66 – 90 | Helical3 PublicationsAdd BLAST | 25 | |
Topological domaini | 91 – 119 | Periplasmic3 PublicationsAdd BLAST | 29 | |
Transmembranei | 120 – 142 | Helical3 PublicationsAdd BLAST | 23 | |
Topological domaini | 143 – 146 | Cytoplasmic3 Publications | 4 | |
Transmembranei | 147 – 171 | Helical3 PublicationsAdd BLAST | 25 | |
Topological domaini | 172 – 185 | Periplasmic3 PublicationsAdd BLAST | 14 | |
Transmembranei | 186 – 201 | Helical3 PublicationsAdd BLAST | 16 | |
Topological domaini | 202 – 221 | Cytoplasmic3 PublicationsAdd BLAST | 20 | |
Transmembranei | 222 – 241 | Helical3 PublicationsAdd BLAST | 20 | |
Topological domaini | 242 – 248 | Periplasmic3 Publications | 7 | |
Transmembranei | 249 – 273 | Helical3 PublicationsAdd BLAST | 25 | |
Topological domaini | 274 – 279 | Cytoplasmic3 Publications | 6 | |
Transmembranei | 280 – 300 | Helical3 PublicationsAdd BLAST | 21 | |
Topological domaini | 301 – 302 | Periplasmic3 Publications | 2 | |
Transmembranei | 303 – 321 | Helical3 PublicationsAdd BLAST | 19 | |
Topological domaini | 322 – 333 | Cytoplasmic3 PublicationsAdd BLAST | 12 | |
Transmembranei | 334 – 355 | Helical3 PublicationsAdd BLAST | 22 | |
Topological domaini | 356 – 370 | Periplasmic3 PublicationsAdd BLAST | 15 | |
Transmembranei | 371 – 399 | Helical3 PublicationsAdd BLAST | 29 | |
Topological domaini | 400 – 428 | Cytoplasmic4 PublicationsAdd BLAST | 29 |
Keywords - Cellular componenti
Cell inner membrane, Cell membrane, MembranePathology & Biotechi
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 129 | F → A: 1.4-fold increase in transport activity with methylammonium as substrate. Shows 80% inhibition by thallium. 1 Publication | 1 | |
Mutagenesisi | 170 | W → A: 2.5-fold increase in transport activity with methylammonium as substrate. Shows 80% inhibition by thallium. 1 Publication | 1 | |
Mutagenesisi | 170 | W → L: 5-fold increase in transport activity with methylammonium as substrate. 1 Publication | 1 | |
Mutagenesisi | 178 | H → A: Abolishes the positive allosteric modulation observed for binding phosphatidylethanolamine and cardiolipin-like molecules. 1 Publication | 1 | |
Mutagenesisi | 182 | D → A: Impairs ammonium transport. Loss of activity with methylammonium as substrate. GlnK remains fully uridylylated and localizes to the cytoplasm during a transient increase in extracellular ammonium. 2 Publications | 1 | |
Mutagenesisi | 182 | D → E: Impairs ammonium transport. Retains 71% of wild-type activity with methylammonium as substrate. Allows some complex formation with GlnK during a transient increase in extracellular ammonium. 2 Publications | 1 | |
Mutagenesisi | 190 | H → A: Does not prevent transport of ammonia. Loss of transport activity with methylammonium and methylamine. Shows normal GlnK-AmtB complex formation after ammonium shock. Loss of both methylamine and ammonia transport; when associated with A-340. 3 Publications | 1 | |
Mutagenesisi | 190 | H → D, F, N or Q: Loss of transport activity with methylammonium as substrate. Shows normal GlnK-AmtB complex formation after ammonium shock. 1 Publication | 1 | |
Mutagenesisi | 190 | H → E: Retains 25% of transport activity with methylammonium as substrate. Shows normal GlnK-AmtB complex formation after ammonium shock. 1 Publication | 1 | |
Mutagenesisi | 190 | H → K: Loss of transport activity with methylammonium as substrate. 1 Publication | 1 | |
Mutagenesisi | 190 | H → T: Loss of transport activity with methylammonium as substrate. Cannot form GlnK-AmtB complex after ammonium shock. 1 Publication | 1 | |
Mutagenesisi | 234 | W → A: Loss of transport activity with methylammonium as substrate. 1 Publication | 1 | |
Mutagenesisi | 234 | W → F: Retains 80% of transport activity with methylammonium as substrate. 1 Publication | 1 | |
Mutagenesisi | 237 | F → A, H, L, Q, S or W: Loss of transport activity with methylammonium as substrate. 1 Publication | 1 | |
Mutagenesisi | 241 | S → A: 4-fold increase in transport activity with methylammonium as substrate. Shows 80% inhibition by thallium. 1 Publication | 1 | |
Mutagenesisi | 340 | H → A: Does not prevent transport of ammonia. Loss of transport activity with methylammonium and methylamine. Shows normal GlnK-AmtB complex formation after ammonium shock. Loss of both methylamine and ammonia transport; when associated with A-190. 3 Publications | 1 | |
Mutagenesisi | 340 | H → E or F: Loss of transport activity with methylammonium as substrate. Shows normal GlnK-AmtB complex formation after ammonium shock. 1 Publication | 1 | |
Mutagenesisi | 340 | H → T: Loss of transport activity with methylammonium as substrate. 1 Publication | 1 | |
Mutagenesisi | 404 – 428 | Missing : Reduced methylamine transport activity. Cannot interact with GlnK. 1 PublicationAdd BLAST | 25 | |
Mutagenesisi | 405 – 428 | Missing : Retains 27% of wild-type activity. 1 PublicationAdd BLAST | 24 | |
Mutagenesisi | 406 | R → A: Almost loss of activity. 1 Publication | 1 | |
Mutagenesisi | 415 | G → A, D, E, N or R: Almost loss of activity. 1 Publication | 1 | |
Mutagenesisi | 421 – 428 | Missing : Retains 43% of wild-type activity. 1 Publication | 8 | |
Mutagenesisi | 426 – 428 | Missing : Retains 21% of wild-type activity. 1 Publication | 3 | |
Mutagenesisi | 426 | Y → G: Retains 11% of wild-type activity. 1 Publication | 1 | |
Mutagenesisi | 427 – 428 | Missing : Retains 12% of wild-type activity. 1 Publication | 2 | |
Mutagenesisi | 427 | N → A: Retains 33% of wild-type activity. 1 Publication | 1 | |
Mutagenesisi | 427 | N → D: No change in activity. 1 Publication | 1 | |
Mutagenesisi | 427 | N → Q: Retains 28% of wild-type activity. 1 Publication | 1 | |
Mutagenesisi | 428 | Missing : No change in activity. 1 Publication | 1 |
Chemistry databases
DrugBanki | DB04147, Dodecyldimethylamine N-oxide DB01828, Methylamine |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Signal peptidei | 1 – 22 | 1 PublicationAdd BLAST | 22 | |
ChainiPRO_0000001307 | 23 – 428 | Ammonium transporter AmtBAdd BLAST | 406 |
Proteomic databases
jPOSTi | P69681 |
PaxDbi | P69681 |
PRIDEi | P69681 |
Interactioni
Subunit structurei
Homotrimer (PubMed:12023896, PubMed:15563598, PubMed:15361618, PubMed:17040913). In response to elevation of the extracellular ammonium concentration, interacts and forms a complex with GlnK (PubMed:10637624, PubMed:11847102, PubMed:14668330, PubMed:17220269, PubMed:17190799, PubMed:16864585, PubMed:20639578).
Interacts with GlnK with a stoichiometry of AmtB3:GlnK3 (PubMed:17220269, PubMed:17190799). Sequestration of GlnK is reversible (PubMed:14668330).
11 PublicationsBinary interactionsi
P69681
With | #Exp. | IntAct |
---|---|---|
itself | 4 | EBI-9137905,EBI-9137905 |
glnK [P0AC55] | 3 | EBI-9137905,EBI-559503 |
GO - Molecular functioni
- identical protein binding Source: IntAct
Protein-protein interaction databases
BioGRIDi | 4259856, 9 interactors 849473, 3 interactors |
DIPi | DIP-29874N |
IntActi | P69681, 3 interactors |
STRINGi | 511145.b0451 |
Structurei
Secondary structure
3D structure databases
PCDDBi | P69681 |
SMRi | P69681 |
ModBasei | Search... |
PDBe-KBi | Search... |
Miscellaneous databases
EvolutionaryTracei | P69681 |
Family & Domainsi
Domaini
Sequence similaritiesi
Keywords - Domaini
Signal, Transmembrane, Transmembrane helixPhylogenomic databases
eggNOGi | COG0004, Bacteria |
HOGENOMi | CLU_000445_33_0_6 |
InParanoidi | P69681 |
PhylomeDBi | P69681 |
Family and domain databases
Gene3Di | 1.10.3430.10, 1 hit |
InterProi | View protein in InterPro IPR029020, Ammonium/urea_transptr IPR001905, Ammonium_transpt IPR018047, Ammonium_transpt_CS IPR024041, NH4_transpt_AmtB-like_dom |
PANTHERi | PTHR43029, PTHR43029, 1 hit |
Pfami | View protein in Pfam PF00909, Ammonium_transp, 1 hit |
TIGRFAMsi | TIGR00836, amt, 1 hit |
PROSITEi | View protein in PROSITE PS01219, AMMONIUM_TRANSP, 1 hit |
i Sequence
Sequence statusi: Complete.
: The displayed sequence is further processed into a mature form. Sequence processingi
10 20 30 40 50
MKIATIKTGL ASLAMLPGLV MAAPAVADKA DNAFMMICTA LVLFMTIPGI
60 70 80 90 100
ALFYGGLIRG KNVLSMLTQV TVTFALVCIL WVVYGYSLAF GEGNNFFGNI
110 120 130 140 150
NWLMLKNIEL TAVMGSIYQY IHVAFQGSFA CITVGLIVGA LAERIRFSAV
160 170 180 190 200
LIFVVVWLTL SYIPIAHMVW GGGLLASHGA LDFAGGTVVH INAAIAGLVG
210 220 230 240 250
AYLIGKRVGF GKEAFKPHNL PMVFTGTAIL YIGWFGFNAG SAGTANEIAA
260 270 280 290 300
LAFVNTVVAT AAAILGWIFG EWALRGKPSL LGACSGAIAG LVGVTPACGY
310 320 330 340 350
IGVGGALIIG VVAGLAGLWG VTMLKRLLRV DDPCDVFGVH GVCGIVGCIM
360 370 380 390 400
TGIFAASSLG GVGFAEGVTM GHQLLVQLES IAITIVWSGV VAFIGYKLAD
410 420
LTVGLRVPEE QEREGLDVNS HGENAYNA
Experimental Info
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Sequence conflicti | 377 – 382 | QLESIA → SWKASP in M63308 (PubMed:1645722).Curated | 6 |
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U40429 Genomic DNA Translation: AAD14837.1 U82664 Genomic DNA Translation: AAB40207.1 U00096 Genomic DNA Translation: AAC73554.1 AP009048 Genomic DNA Translation: BAE76231.1 M63308 Genomic DNA No translation available. |
PIRi | A90692 C64775 E85542 |
RefSeqi | NP_414985.1, NC_000913.3 WP_000685029.1, NZ_STEB01000007.1 |
Genome annotation databases
EnsemblBacteriai | AAC73554; AAC73554; b0451 BAE76231; BAE76231; BAE76231 |
GeneIDi | 67416474 945084 |
KEGGi | ecj:JW0441 eco:b0451 |
PATRICi | fig|1411691.4.peg.1824 |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U40429 Genomic DNA Translation: AAD14837.1 U82664 Genomic DNA Translation: AAB40207.1 U00096 Genomic DNA Translation: AAC73554.1 AP009048 Genomic DNA Translation: BAE76231.1 M63308 Genomic DNA No translation available. |
PIRi | A90692 C64775 E85542 |
RefSeqi | NP_414985.1, NC_000913.3 WP_000685029.1, NZ_STEB01000007.1 |
3D structure databases
Select the link destinations: PDBei RCSB PDBi PDBji Links Updated | PDB entry | Method | Resolution (Å) | Chain | Positions | PDBsum |
1U77 | X-ray | 2.00 | A | 23-407 | [»] | |
1U7C | X-ray | 1.85 | A | 23-407 | [»] | |
1U7G | X-ray | 1.40 | A | 23-407 | [»] | |
1XQE | X-ray | 2.10 | A | 23-428 | [»] | |
1XQF | X-ray | 1.80 | A | 23-428 | [»] | |
2NMR | X-ray | 2.10 | A | 23-428 | [»] | |
2NOP | X-ray | 2.00 | A | 23-428 | [»] | |
2NOW | X-ray | 2.20 | A | 23-428 | [»] | |
2NPC | X-ray | 2.10 | A | 23-428 | [»] | |
2NPD | X-ray | 2.10 | A | 23-428 | [»] | |
2NPE | X-ray | 2.10 | A | 23-428 | [»] | |
2NPG | X-ray | 2.00 | A | 23-428 | [»] | |
2NPJ | X-ray | 2.00 | A | 23-428 | [»] | |
2NPK | X-ray | 2.00 | A | 23-428 | [»] | |
2NS1 | X-ray | 1.96 | A | 23-428 | [»] | |
2NUU | X-ray | 2.50 | A/B/C/D/E/F | 25-428 | [»] | |
3C1G | X-ray | 2.30 | A | 23-428 | [»] | |
3C1H | X-ray | 2.20 | A | 23-428 | [»] | |
3C1I | X-ray | 2.30 | A | 23-428 | [»] | |
3C1J | X-ray | 2.00 | A | 23-428 | [»] | |
6B21 | X-ray | 2.45 | A | 26-428 | [»] | |
PCDDBi | P69681 | |||||
SMRi | P69681 | |||||
ModBasei | Search... | |||||
PDBe-KBi | Search... |
Protein-protein interaction databases
BioGRIDi | 4259856, 9 interactors 849473, 3 interactors |
DIPi | DIP-29874N |
IntActi | P69681, 3 interactors |
STRINGi | 511145.b0451 |
Chemistry databases
DrugBanki | DB04147, Dodecyldimethylamine N-oxide DB01828, Methylamine |
Protein family/group databases
TCDBi | 1.A.11.1.1, the ammonium transporter channel (amt) family |
Proteomic databases
jPOSTi | P69681 |
PaxDbi | P69681 |
PRIDEi | P69681 |
Genome annotation databases
EnsemblBacteriai | AAC73554; AAC73554; b0451 BAE76231; BAE76231; BAE76231 |
GeneIDi | 67416474 945084 |
KEGGi | ecj:JW0441 eco:b0451 |
PATRICi | fig|1411691.4.peg.1824 |
Organism-specific databases
EchoBASEi | EB1768 |
Phylogenomic databases
eggNOGi | COG0004, Bacteria |
HOGENOMi | CLU_000445_33_0_6 |
InParanoidi | P69681 |
PhylomeDBi | P69681 |
Enzyme and pathway databases
BioCyci | EcoCyc:AMTB-MONOMER |
Miscellaneous databases
EvolutionaryTracei | P69681 |
PROi | PR:P69681 |
Family and domain databases
Gene3Di | 1.10.3430.10, 1 hit |
InterProi | View protein in InterPro IPR029020, Ammonium/urea_transptr IPR001905, Ammonium_transpt IPR018047, Ammonium_transpt_CS IPR024041, NH4_transpt_AmtB-like_dom |
PANTHERi | PTHR43029, PTHR43029, 1 hit |
Pfami | View protein in Pfam PF00909, Ammonium_transp, 1 hit |
TIGRFAMsi | TIGR00836, amt, 1 hit |
PROSITEi | View protein in PROSITE PS01219, AMMONIUM_TRANSP, 1 hit |
MobiDBi | Search... |
Entry informationi
Entry namei | AMTB_ECOLI | |
Accessioni | P69681Primary (citable) accession number: P69681 Secondary accession number(s): P37905, Q2MBX5 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | March 29, 2005 |
Last sequence update: | March 29, 2005 | |
Last modified: | February 23, 2022 | |
This is version 135 of the entry and version 1 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Prokaryotic Protein Annotation Program |
Miscellaneousi
Keywords - Technical termi
3D-structure, Direct protein sequencing, Reference proteomeDocuments
- PDB cross-references
Index of Protein Data Bank (PDB) cross-references - SIMILARITY comments
Index of protein domains and families