Transporter Classification Database

A Transporter Classification Database ou TCDB (Base de Datos de Clasificación de Transportadores) é un sistema de clasificación aprobado pola International Union of Biochemistry and Molecular Biology (IUBMB) para as proteínas transportadoras de membrana incluíndo os canais iónicos. Este sistema de clasificación foi deseñado para que fose análogo ao sistema do número EC para a clasificación de encimas, pero utiliza tamén información filoxenética.

Clasificación

Velaquí o nivelsuperior de clasificación e algúns exemplos de proteínas con estrutura tridimensional coñecida:

1. Cnais/Poros

1.A Canais de tipo α

• 1.A.1 Voltage-gated ion channel superfamily
• 1.A.2 Animal inward-rectifier K+ channel
• 1.A.3 Ryanodine-inositol-1,4,5-trisphosphate receptor Ca2+ channel
• 1.A.4 Transient receptor potential Ca2+ channel
• 1.A.5 Polycystin cation channel
• 1.A.6 Epithelial Na+ channel
• 1.A.7 ATP-gated cation channel
• 1.A.8 Major intrinsic protein
• 1.A.9 Ligand-gated ion channel of neurotransmitter receptors
• 1.A.10 Glutamate-gated ion channel of neurotransmitter receptors
• 1.A.11 Chloride channel
• 1.A.12 Organellar chloride channel
• 1.A.13 Epithelial chloride channel
• 1.A.14 Nonselective cation channel-1
• 1.A.15 Nonselective cation channel-2
• 1.A.16 Yeast stretch-activated, cation-selective, Ca2+ channel
• 1.A.17 Chloroplast outer-membrane solute channel
• 1.A.18 Chloroplast membrane anion-channel-former
• 1.A.19 Influenza virus matrix-2 channel
• 1.A.20 gp91phox phagocyte NADPH-oxidase-associated cyt b558 H+-channel
• 1.A.21 Apoptosis regulator
• 1.A.22 Large-conductance mechanosensitive ion channel
• 1.A.23 Small-conductance mechanosensitive ion channel
• 1.A.24 Gap-junction-forming connexin
• 1.A.25 Gap-junction-forming innexin
• 1.A.26 Plant plasmodesmata
• 1.A.27 Phospholemman
• 1.A.28 Urea transporter (channel)
• 1.A.29 Urea/amide channel
• 1.A.30 H+- or Na+-translocating bacterial MotAB flagellar motor/ExbBD outer-membrane transport energizer superfamily
• 1.A.31 Annexin
• 1.A.32 Type B influenza virus NB channel
• 1.A.33 Cation-channel-forming heat-shock protein 70
• 1.A.34 Envelope virus E1 channel
• 1.A.35 Metal-ion transporter (channel)
• 1.A.36 Intracellular chloride channel

1.I Membrane-bound channels

• 1.I.1 Nuclear pore complex family, including karyopherins
• 1.I.2 Plant plasmodesmata family

Ungrouped

• Voltage-gated ion channel like, including potassium channels KcsA and KvAP, and inward-rectifier potassium ion channel Kirbac
• Large-conductance mechanosensitive channel, MscL
• Small-conductance mechanosensitive ion channel (MscS)
• CorA metal ion transporters
• Ligand-gated ion channel of neurotransmitter receptors (acetylcholine receptor)
• Aquaporins
• Chloride channels
• Outer membrane auxiliary proteins (polysaccharide transporter)
• Porins and some other beta barrel proteins of outer membranes

2. Electrochemical Potential-driven Transporters

Ungrouped

• Mitochondrial carrier proteins
• Major Facilitator Superfamily (Glycerol-3-phosphate transporter, Lactose permease, and Multidrug transporter EmrD)
• Resistance-nodulation-cell division (multidrug efflux transporter AcrB, see multidrug resistance)
• Dicarboxylate/amino acid:cation symporter (proton glutamate symporter)
• Monovalent cation/proton antiporter (Sodium/proton antiporter 1 NhaA)
• Neurotransmitter sodium symporter
• Ammonia transporters
• Drug/Metabolite Transporter (small multidrug resistance transporter EmrE - the structures are retracted as erroneous)

3. Primary Active Transporters

3.A. P-P-bond hydrolysis-driven transporters

• P-type calcium ATPase (five different conformations)
• Calcium ATPase regulators phospholamban and sarcolipin
• ABC transporters: BtuCD, multidrug transporter, and molybdate uptake transporter
• General secretory pathway (Sec) translocon (preprotein translocase SecY)

3.D. Oxidoreduction-driven transporters

• Transmembrane cytochrome b-like proteins: coenzyme Q - cytochrome c reductase (cytochrome bc1 ); cytochrome b6f complex; formate dehydrogenase, respiratory nitrate reductase; succinate - coenzyme Q reductase (fumarate reductase); and succinate dehydrogenase. See electron transport chain.
• Cytochrome c oxidases from bacteria and mitochondria

3.E. Light absorption-driven transporters

• Bacteriorhodopsin-like proteins including rhodopsin (see also opsin)
• Bacterial photosynthetic reaction centres and photosystems I and II
• Light harvesting complexes from bacteria and chloroplasts

Ungrouped Electrochemical potential-driven transporters

• Proton or sodium translocating F-type and V-type ATPases

5. Transport Electron Carriers

Non agrupados

• Disulfide bond formation protein B (DsbB)

6. Unused

Reserved for future expansion

7. Non usados

Reserved for future expansion

Exemplos

• Regulador da condutancia transmembrana da fibrose quística—3.A.1.202.1

Véxase tamén

Ligazóns externas

• Transporter Classification Database
• List en qmul.ac.uk

• Saier MH, Tran CV, Barabote RD (January 2006). "TCDB: the Transporter Classification Database for membrane transport protein analyses and information". Nucleic Acids Res. 34 (Database issue): D181–6. PMC 1334385. PMID 16381841. doi:10.1093/nar/gkj001. 

• Busch W, Saier MH (2002). "The transporter classification (TC) system, 2002". Crit. Rev. Biochem. Mol. Biol. 37 (5): 287–337. PMID 12449427. doi:10.1080/10409230290771528.