Major Facilitator Superfamily; The Major Facilitator Superfamily (MFS) is a large and diverse group of secondary transporters that includes uniporters, symporters, and antiporters. MFS proteins facilitate the transport across cytoplasmic or internal membranes of a variety of substrates including ions, sugar phosphates, drugs, neurotransmitters, nucleosides, amino acids, and peptides. They do so using the electrochemical potential of the transported substrates. Uniporters transport a single substrate, while symporters and antiporters transport two substrates in the same or in opposite directions, respectively, across membranes. MFS proteins are typically 400 to 600 amino acids in length, and the majority contain 12 transmembrane alpha helices (TMs) connected by hydrophilic loops. The N- and C-terminal halves of these proteins display weak similarity and may be the result of a gene duplication/fusion event. Based on kinetic studies and the structures of a few bacterial superfamily members, GlpT (glycerol-3-phosphate transporter), LacY (lactose permease), and EmrD (multidrug transporter), MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement. Bacterial members function primarily for nutrient uptake, and as drug-efflux pumps to confer antibiotic resistance. Some MFS proteins have medical significance in humans such as the glucose transporter Glut4, which is impaired in type II diabetes, and glucose-6-phosphate transporter (G6PT), which causes glycogen storage disease when mutated.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 214 FESATMEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:cd17317   10 ESTIVTEWDLVCDRDWLVALVQTIFFLGVLIGSLLFGYLADRFGRRPVLLLGLVLQIVCGVLSAFSPSYELFLVLRFLVG 89

                         90
                 ....*....|....
gi 386770662 294 ASYDTCFTMVYILG 307
Cdd:cd17317   90 VTSAGIFTVGFVLG 103

Solute carrier 22 (SLC22) family of organic cation/anion/zwitterion transporters of the Major Facilitator Superfamily; The Solute carrier 22 (SLC22) family of organic cation/anion/zwitterion transporters includes organic cation transporters (OCTs), organic zwitterion/cation transporters (OCTNs), and organic anion transporters (OATs). SLC22 transporters interact with a variety of compounds that include drugs of abuse, environmental toxins, opioid analgesics, antidepressant and anxiolytic agents, and neurotransmitters and their metabolites. The SLC22 family belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 214 FESATMEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:cd17317   10 ESTIVTEWDLVCDRDWLVALVQTIFFLGVLIGSLLFGYLADRFGRRPVLLLGLVLQIVCGVLSAFSPSYELFLVLRFLVG 89

                         90
                 ....*....|....
gi 386770662 294 ASYDTCFTMVYILG 307
Cdd:cd17317   90 VTSAGIFTVGFVLG 103

Predicted arabinose efflux permease AraJ, MFS family [Carbohydrate transport and metabolism];

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 386770662 237 IFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVGAS 295
Cdd:COG2814   53 AYLLGAALGAPLAGRLADRFGRRRVLLLGLLLFALGSLLCALAPSLWLLLAARFLQGLG 111

benzoate transport; [Transport and binding proteins, Carbohydrates, organic alcohols, and acids]

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 386770662  240 LGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFL----VGASYDTCFTMV 303
Cdd:TIGR00895  63 IGMAFGALFFGPLADRIGRRRVLLWSILLFSVFTLLCALATNVTQLLILRFLaglgLGGLMPNLNALV 130

Solute carrier 22 (SLC22) family of organic cation/anion/zwitterion transporters of the Major Facilitator Superfamily; The Solute carrier 22 (SLC22) family of organic cation/anion/zwitterion transporters includes organic cation transporters (OCTs), organic zwitterion/cation transporters (OCTNs), and organic anion transporters (OATs). SLC22 transporters interact with a variety of compounds that include drugs of abuse, environmental toxins, opioid analgesics, antidepressant and anxiolytic agents, and neurotransmitters and their metabolites. The SLC22 family belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 214 FESATMEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:cd17317   10 ESTIVTEWDLVCDRDWLVALVQTIFFLGVLIGSLLFGYLADRFGRRPVLLLGLVLQIVCGVLSAFSPSYELFLVLRFLVG 89

                         90
                 ....*....|....
gi 386770662 294 ASYDTCFTMVYILG 307
Cdd:cd17317   90 VTSAGIFTVGFVLG 103

Solute carrier family 22 member 7 (also called Organic anion transporter 2) of the Major Facilitator Superfamily of transporters; Solute carrier family 22 member 7 (SLC22A7), also called organic anion transporter 2 (OAT2) mediates sodium-independent transport of a variety of organic anions including prostaglandin E2, prostaglandin F2, tetracycline, bumetanide, estrone sulfate, glutarate, dehydroepiandrosterone sulfate, allopurinol, 5-fluorouracil, paclitaxel, L-ascorbic acid, salicylate, ethotrexate, and alpha-ketoglutarate. It also plays a role in renal uric acid uptake from blood as a first step of tubular secretion. OAT2 belongs to the Solute carrier 22 (SLC22) family of organic cation/anion/zwitterion transporters of the Major Facilitator Superfamily (MFS)of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 195 SLPTIPCKKGYVFEQEGRAFESATmEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSL 274
Cdd:cd17447    2 DLPVVPCQNGWVYDHSTFSSTIAT-EWDLVCDRKGLNQATATFFFAGVTMGAVAFGYLSDRFGRKRMLLVAYVLSLVFGL 80

                         90
                 ....*....|....*....
gi 386770662 275 ATSMSTDFFTFAISRFLVG 293
Cdd:cd17447   81 ASAFSVSYVMFAITRTLTG 99

Solute carrier family 22 members 1, 2, and 3 (also called Organic cation transporters 1, 2, and 3) of the Major Facilitator Superfamily of transporters; This sufamily includes solute carrier family 22 member 1 (SLC22A1, also called organic cation transporter 1 or OCT1), SLC22A2 (or OCT2), SLC22A3 (or OCT3), and similar proteins. OCT1-3 have similar basic functional properties: they are able to translocate a variety of structurally different organic cations in both directions across the plasma membrane; to translocate organic cations independently from sodium, chloride or proton gradients; and to function as electrogenic uniporters for cations or as electroneutral cation exchangers. They show overlapping but distinct substrate and inhibitor specificities, and different tissue expression pattern. In humans, OCT1 is strongly expressed in the liver, OCT2 is highly expressed in the kidney where it is localized at the basolateral membrane of renal proximal tubules, and OCT3 is most strongly expressed in skeletal muscle. OCTs are broad-specificity transporters that play a critical role in the excretion and distribution of endogeneous organic cations and for the uptake, elimination and distribution of cationic drugs, toxins, and environmental waste products. The SLC22A1-3 subfamily belongs to the Solute carrier 22 (SLC22) family of organic cation/anion/zwitterion transporters of the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 194 TSLPTIPCKKGYVFEQEGRAFESatmEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGS 273
Cdd:cd17379    1 SMLPLSPCQDGWVYNTPRSSIVT---EFNLVCEDAWKLDLFQSSLNLGFLIGSIVIGYLADRFGRKVCFLISILGNGVSG 77

                         90       100       110
                 ....*....|....*....|....*....|...
gi 386770662 274 LATSMSTDFFTFAISRFLVGASYDTCFTMVYIL 306
Cdd:cd17379   78 VLMAFSPNYPWFLIFRFLQGLFGKGGWMTGYVL 110

Solute carrier family 22 member 16 (also called Carnitine transporter 2) of the Major Facilitator Superfamily of transporters; Solute carrier family 22 member 16 (SLC22A16) is also called carnitine transporter 2 (CT2), fly-like putative transporter 2 (FLIPT2), organic cation transporter OKB1, or organic cation/carnitine transporter 6 (OCT6). It is a partially sodium-ion dependent high affinity carnitine transporter. It also transports organic cations such as tetraethylammonium (TEA) and doxorubicin. It is one of several organic cation transporters (OCTs) that falls into the SLC22 (solute carrier 22) family. OCTs are broad-specificity transporters that play a critical role in the excretion and distribution of endogeneous organic cations and for the uptake, elimination and distribution of cationic drugs, toxins, and environmental waste products. SLC22A16 belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 200 PCKKGYVFEQEgRAFESATMEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMS 279
Cdd:cd17375    7 SCSDGFVYDQS-KWESSIVTDWDLVCDREWLAKLIQPIFMLGVLLGAVIFGDIADRIGRRPVLWFTSTGQFVFGIAVAFT 85

                         90
                 ....*....|...
gi 386770662 280 TDFFTFAISRFLV 292
Cdd:cd17375   86 FDYYSFVIVRFLL 98

Solute carrier family 22, member 31 of the Major Facilitator Superfamily; Solute carrier family 22, member 31 (SLC22A31) is an uncharacterized member of the SLC22 family of transporters, which includes organic cation transporters (OCTs), organic zwitterion/cation transporters (OCTNs), and organic anion transporters (OATs). SLC22 transporters interact with a variety of compounds that include drugs of abuse, environmental toxins, opioid analgesics, antidepressant and anxiolytic agents, and neurotransmitters and their metabolites. SLC22A31 belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 198 TIPCKKGYVFEQEGRAFESATMEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATS 277
Cdd:cd17443    5 AVLCTGGWPFSAAAGLGSNLVTEWNLVCDDGWKVPLEKISYLLGWLLGYIILGAGCDRLGRRAAFVLSLVLATLLGVSVA 84

                         90       100
                 ....*....|....*....|....*...
gi 386770662 278 MSTDFFTFAISRFLVGASYDTCFTMVYI 305
Cdd:cd17443   85 LSASPPTFLVLRLLQGGTLAGVFLSLYI 112

Major Facilitator Superfamily;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662  237 IFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVGASYDTCFTMVYIL 306
Cdd:pfam07690  40 LFSLGYALAQPLAGRLSDRFGRRRVLLIGLLLFALGLLLLLFASSLWLLLVLRVLQGLGAGALFPAALAL 109

MFS family permease, includes anhydromuropeptide permease AmpG [Carbohydrate transport and metabolism, Amino acid transport and metabolism, Inorganic ion transport and metabolism, General function prediction only];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 192 INTSLPTIpckkgyvfeqeGRAFESATMEFGWLCDddkyatyaqiIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALV 271
Cdd:COG0477   33 VNVALPSI-----------AADLGASSAQLGWIVS----------AYLLGRAIGLLLFGRLGDRYGRKRVLLIGLLLFGL 91

                         90       100
                 ....*....|....*....|..
gi 386770662 272 GSLATSMSTDFFTFAISRFLVG 293
Cdd:COG0477   92 ASLLCGLAPSPELLIAARALQG 113

Major Facilitator Superfamily; The Major Facilitator Superfamily (MFS) is a large and diverse group of secondary transporters that includes uniporters, symporters, and antiporters. MFS proteins facilitate the transport across cytoplasmic or internal membranes of a variety of substrates including ions, sugar phosphates, drugs, neurotransmitters, nucleosides, amino acids, and peptides. They do so using the electrochemical potential of the transported substrates. Uniporters transport a single substrate, while symporters and antiporters transport two substrates in the same or in opposite directions, respectively, across membranes. MFS proteins are typically 400 to 600 amino acids in length, and the majority contain 12 transmembrane alpha helices (TMs) connected by hydrophilic loops. The N- and C-terminal halves of these proteins display weak similarity and may be the result of a gene duplication/fusion event. Based on kinetic studies and the structures of a few bacterial superfamily members, GlpT (glycerol-3-phosphate transporter), LacY (lactose permease), and EmrD (multidrug transporter), MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement. Bacterial members function primarily for nutrient uptake, and as drug-efflux pumps to confer antibiotic resistance. Some MFS proteins have medical significance in humans such as the glucose transporter Glut4, which is impaired in type II diabetes, and glucose-6-phosphate transporter (G6PT), which causes glycogen storage disease when mutated.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 386770662 230 YATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVGASYDTCFTMV 303
Cdd:cd06174   32 QLGLLFALFSLGYALLQPLAGLLADRFGRRPVLLLGLLLFALGALLFAFAPSFWLLLLGRFLLGLGSGLIDPAV 105

4-hydroxybenzoate transporter PcaK and similar transporters of the Major Facilitator Superfamily; This aromatic acid:H(+) symporter subfamily includes Acinetobacter sp. 4-hydroxybenzoate transporter PcaK, Pseudomonas putida gallate transporter (GalT), Corynebacterium glutamicum gentisate transporter (GenK), Nocardioides sp. 1-hydroxy-2-naphthoate transporter (PhdT), Escherichia coli 3-(3-hydroxy-phenyl)propionate (3HPP) transporter (MhpT), and similar proteins. These transporters are involved in the uptake across the cytoplasmic membrane of specific aromatic compounds such as 4-hydroxybenzoate, gallate, gentisate (2,5-dihydroxybenzoate), 1-hydroxy-2-naphthoate, and 3HPP, respectively. The PcaK-like aromatic acid:H(+) symporter subfamily belongs to the Metazoan Synaptic Vesicle Glycoprotein 2 (SV2) and related small molecule transporter family (SV2-like) of the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 386770662 239 FLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFL----VGASYDTCFTMV 303
Cdd:cd17365   44 LFGMAIGALLAGPLADRFGRKRVLLVSVALFGLFTLLTAFAQSVLQLALLRFLtglgLGAAMPNAITLV 112

benzoate transport; [Transport and binding proteins, Carbohydrates, organic alcohols, and acids]

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 386770662  240 LGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFL----VGASYDTCFTMV 303
Cdd:TIGR00895  63 IGMAFGALFFGPLADRIGRRRVLLWSILLFSVFTLLCALATNVTQLLILRFLaglgLGGLMPNLNALV 130

Glucose transporters (GLUTs) and other similar sugar transporters of the Major Facilitator Superfamily; This family is composed of glucose transporters (GLUTs) and other sugar transporters including fungal hexose transporters (HXT), bacterial xylose transporter (XylE), plant sugar transport proteins (STP) and polyol transporters (PLT), H(+)-myo-inositol cotransporter (HMIT), and similar proteins. GLUTs, also called Solute carrier family 2, facilitated glucose transporters (SLC2A), are a family of proteins that facilitate the transport of hexoses such as glucose and fructose. There are fourteen GLUTs found in humans; they display different substrate specificities and tissue expression. They have been categorized into three classes based on sequence similarity: Class 1 (GLUTs 1-4, 14); Class 2 (GLUTs 5, 7, 9, and 11); and Class 3 (GLUTs 6, 8, 10, 12, and HMIT). GLUT proteins are comprised of about 500 amino acid residues, possess a single N-linked oligosaccharide, and have 12 transmembrane segments. The GLUT-like family belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 386770662 237 IFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:cd17315   42 SLLLGAAIGSLFGGPLADRFGRRKSLLIAAVLYVIGALLSALAPNVWVLIVGRFLLG 98

Major Facilitator Superfamily; The Major Facilitator Superfamily (MFS) is a large and diverse group of secondary transporters that includes uniporters, symporters, and antiporters. MFS proteins facilitate the transport across cytoplasmic or internal membranes of a variety of substrates including ions, sugar phosphates, drugs, neurotransmitters, nucleosides, amino acids, and peptides. They do so using the electrochemical potential of the transported substrates. Uniporters transport a single substrate, while symporters and antiporters transport two substrates in the same or in opposite directions, respectively, across membranes. MFS proteins are typically 400 to 600 amino acids in length, and the majority contain 12 transmembrane alpha helices (TMs) connected by hydrophilic loops. The N- and C-terminal halves of these proteins display weak similarity and may be the result of a gene duplication/fusion event. Based on kinetic studies and the structures of a few bacterial superfamily members, GlpT (glycerol-3-phosphate transporter), LacY (lactose permease), and EmrD (multidrug transporter), MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement. Bacterial members function primarily for nutrient uptake, and as drug-efflux pumps to confer antibiotic resistance. Some MFS proteins have medical significance in humans such as the glucose transporter Glut4, which is impaired in type II diabetes, and glucose-6-phosphate transporter (G6PT), which causes glycogen storage disease when mutated.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 231 ATYAQIIFFLGSILGGLAYGHFAD-HCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVGASYDTCFTMVYILGKK 309
Cdd:cd06174  241 AGLLLSLFGLAGALGSLLLGLLSDrLIGRKPLLLIGLLLMALGLALLLLAPSLLLLLLLLLLLGFGLGGLLPLSFALIAE 320

                 ....
gi 386770662 310 VHIP 313
Cdd:cd06174  321 LFPP 324

Solute carrier family 22 member 15 of the Major Facilitator Superfamily of transporters; Solute carrier family 22 member 15 (SLC22A15) is also called fly-like putative transporter 1 (FLIPT1). It is expressed at the highest levels in the kidney and brain. It is a member of the SLC22 family of transporters, which includes organic cation transporters (OCTs), organic zwitterion/cation transporters (OCTNs), and organic anion transporters (OATs). SLC22 transporters interact with a variety of compounds that include drugs of abuse, environmental toxins, opioid analgesics, antidepressant and anxiolytic agents, and neurotransmitters and their metabolites. SLC22A15 belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 386770662 229 KYATY----AQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:cd17377   35 GNAAYkvslASSFFFAGVLIGVVSFGQLSDRFGRKPVYLTGLALDILFAYFNALAPSYEFFAVSRFLVG 103

H(+)-myo-inositol cotransporter and similar transporters of the Major Facilitator Superfamily; This subfamily is composed of myo-inositol/inositol transporters and similar transporters from vertebrates, plant, and fungi. The human protein is called H(+)-myo-inositol cotransporter/Proton myo-inositol cotransporter (HMIT), or H(+)-myo-inositol symporter, or Solute carrier family 2 member 13 (SLC2A13). HMIT is classified as a Class 3 GLUT (glucose transporter) based on sequence similarity with GLUTs, but it does not transport glucose. It specifically transports myo-inositol and is expressed predominantly in the brain, with high expression in the hippocampus, hypothalamus, cerebellum and brainstem. HMIT may be involved in regulating processes that require high levels of myo-inositol or its phosphorylated derivatives, such as membrane recycling, growth cone dynamics, and synaptic vesicle exocytosis. Arabidopsis Inositol transporter 4 (AtINT4) mediates high-affinity H+ symport of myo-inositol across the plasma membrane. The HMIT-like subfamily belongs to the Glucose transporter -like (GLUT-like) family of the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 386770662 240 LGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:cd17360   46 AGAAVGAAIGGWLNDRFGRRPCILLADALFTIGAIVMAAAPNKEVLIVGRVLVG 99

Solute carrier family 22, member 17 and similar proteins of the Major Facilitator Superfamily; This group is composed of Solute carrier family 22, members 17, 23, and 31. They are members of the SLC22 family of organic cation/anion/zwitterion transporters, which includes organic cation transporters (OCTs/OCTNs) and organic anion transporters (OATs). SLC22A17 functions as a cell surface receptor for lipocalin-2 (LCN2), also called NGAL or 24p3, which plays a key role in iron homeostasis and transport. SLC22A23 and SLC22A31 are orphan members of the SLC22 family. SLC22 transporters interact with a variety of compounds that include drugs of abuse, environmental toxins, opioid analgesics, antidepressant and anxiolytic agents, and neurotransmitters and their metabolites. The SLC22A17-like group belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 224 LCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:cd17373   20 VCDNGWKVHLEQFSLLLGLIFGYLILGCIADRFGRRPVLLFSLILILIFGLTVALAVSVTMFSTLRFLEG 89

Solute carrier family 22, member 17 of the Major Facilitator Superfamily; Solute carrier family 22, member 17 (SLC22A17) is also called 24p3 receptor (24p3R), lipocalin-2 receptor, or neutrophil gelatinase-associated lipocalin (NGAL) receptor (NGALR). It functions as a cell surface receptor for lipocalin-2 (LCN2), also called NGAL or 24p3, which plays a key role in iron homeostasis and transport. LCN2 is a secreted protein of the lipocalin family that induces apoptosis in some types of cells and inhibits bacterial growth by sequestration of the iron-laden bacterial siderophore. Over-expressions of NGAL and NGALR have been found to be correlated with unfavorable clinicopathologic features and poor prognosis of patients with hepatocellular carcinoma. SLC22A17 is a member of the SLC22 family of organic cation/anion/zwitterion transporters, which includes organic cation transporters (OCTs/OCTNs) and organic anion transporters (OATs). It belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 201 CKKGYVFEQEGRAFESATMEFGWLCDDDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMST 280
Cdd:cd17445    8 CDAGWNYTGLPGLTNNIVTEWDLVCSRYWLVPLEQVCFILGFASGYLCLGYTADRLGRRRTLLLSLTLAVPFGVLVAVAA 87

                         90       100
                 ....*....|....*....|....*
gi 386770662 281 DFFTFAISRFLVGASYDTCFTMVYI 305
Cdd:cd17445   88 SPSLFMAMRFLLGAALAGVYLTLYL 112

bacterial MdtG-like and eukaryotic solute carrier 18 (SLC18) family of the Major Facilitator Superfamily of transporters; This family is composed of eukaryotic solute carrier 18 (SLC18) family transporters and related bacterial multidrug resistance (MDR) transporters including several proteins from Escherichia coli such as multidrug resistance protein MdtG, from Bacillus subtilis such as multidrug resistance proteins 1 (Bmr1) and 2 (Bmr2), and from Staphylococcus aureus such as quinolone resistance protein NorA. The family also includes Escherichia coli arabinose efflux transporters YfcJ and YhhS. MDR transporters are drug/H+ antiporters (DHA) that mediate the efflux of a variety of drugs and toxic compounds, and confer resistance to these compounds. The SLC18 transporter family includes vesicular monoamine transporters (VAT1 and VAT2), vesicular acetylcholine transporter (VAChT), and SLC18B1, which is proposed to be a vesicular polyamine transporter (VPAT). The MdtG/SLC18 family belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 231 ATYAQI-----IFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVGAS 295
Cdd:cd17325   28 ASVAQIglivaAYALAQLLFSPPAGRLSDRFGRKRLLLLGLLLLAVSTLLFAFATSYWQLLLARFLQGLA 97

putative sialic acid transporter; Provisional

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 386770662 239 FLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:PRK03893  65 FISRWFGGLLLGAMGDRYGRRLAMVISIVLFSVGTLACGFAPGYWTLFIARLVIG 119

MFS transporter;

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 386770662 228 DKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVG 293
Cdd:PRK12307  52 DMEGAFLATAAFIGRPFGGALFGLLADKFGRKPLMMWSIVAYSVGTGLSGLASGVIMLTLSRFIVG 117

Fucose permease [Carbohydrate transport and metabolism];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 386770662 227 DDKYATYAQIIFFLGSILGGLAYGHFADHCGRVAALVSSCFLALVGSLATSMSTDFFTFAISRFLVGASYDTCFTMVYIL 306
Cdd:COG0738  244 SEATAALGLSLFWGGMTIGRFLGGFLLKRFGPVRLLRLSALLAAVGLLLALLAPGPWLALIGLALVGLGLSLMFPTIFSL 323

                 .
gi 386770662 307 G 307
Cdd:COG0738  324 A 324