Transport proteins

Mechanosensitive channels

• Channel of large conductance: MscL
• Channels of small conductance: YfkC, YhdY, YkuT
• Channel implicated in sporulation: SpoVAC
  • a mutant devoid of all four mechanosensitive channels (TMB99, Δ(mscL::spc) Δ(ykuT::cat) Δ(yhdY::ery) Δ(yfkC::kan)) is available in Erhard Bremer's lab PubMed

Ion transporters

Ion uptake

• potassium uptake: KtrA-KtrB, KtrC-KtrD

Ion export

• Na(+)/H(+) antiporter: MrpA-MrpB-MrpC-MrpD-MrpE-MrpF-MrpG
• monovalent cation (Na, K, Li, Rb)/H(+) antiporter: NhaK

ECF transporter for the uptake of micronutrients

• (YbxA-YbaE)-YbaF (general components)
• RibU
• ThiT
• YhfU
• TrpP

Amino acid uptake

• arginine: ArtP-ArtQ-ArtR
• branched-chain amino acids: BraB, BrnQ
• cystine: TcyA-TcyB-TcyC; TcyJ-TcyK-TcyL-TcyM-TcyN
• glutamate: GltP; GltP
• glutamine: GlnH-GlnM-GlnP-GlnQ
• lysine: YvsH
• methionine: MetN-MetP-MetQ
• proline: PutP
• tryptophan: (YbxA-YbaE)-YbaF-TrpP

Nucleotide and nucleoside transporters

Nucleotide and nucleoside uptake

• hypoxanthine/ guanine: PbuG
• hypoxanthine/ guanine: PbuO (based on similarity)

Nucleotide and nucleoside export

• hypoxanthine: PbuE (putative)

Sugar transport proteins

ABC transporters

• ATP-binding subunit for multiple ABC transporters: MsmX
• aminosugar uptake: YurJ-YurM-YurN-YurO
• arabinose uptake: AraN-AraP-AraQ
• galactotriose uptake: CycB-GanP-GanQ
• maltodextrin uptake: MdxE-MdxF-MdxG
• melibiose uptake: AmyC-AmyD-MsmE
• ribose uptake: RbsA-RbsB-RbsC-RbsD

PTS proteins

• General PTS proteins: Enzyme I, HPr
• PtsG: glucose permease, EIICBA
• GamP: glucosamine permease, EIICBA
• MurP: N-acetyl muramic acid-specific phosphotransferase system, EIIBC component
• MtlA, MtlF: mannitol permease
• GmuA, GmuB, GmuC: galactomannan permease
• TreP: trehalose permease
• MalP: maltose permease
• FruA: fructose permease
• ManP: mannose permease
• YpqE: unknown EIIA component
• LevD, LevE, LevF, LevG: fructose permease
• SacP: sucrose permease (high affinity)
• SacY: sucrose permease (low affinity)
• LicA, LicB, LicC: lichenan permease
• BglP: ß-glucoside permease
• YyzE: unknown PTS protein
• YwbA: unknown EIIC component

The PTS in SubtiPathways

• Central C-metabolism
• Sugar catabolism

Transporters for the uptake of compatible solutes in response to hyperosmolarity

• OpuAA-OpuAB-OpuAC: ABC transporter for glycine betaine
• OpuBA-OpuBB-OpuBC-OpuBD: ABC transporter for choline
• OpuCA-OpuCB-OpuCC-OpuCD: ABC transporter for glycine betaine/ carnitine/ choline
• OpuD: transporter for glycine betaine
• OpuE: transporter for proline

Uptake of siderophores

• petrobactin: YclN-YclO-YclP-YclQ

Related Lists

• ABC transporter, PTS

External Links

The Transporter Classification Database