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Test-Species-PubTator

Test-Species-PubDictionaries

{"project":"Test-Species-PubDictionaries","denotations":[{"id":"T1","span":{"begin":36,"end":52},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":241,"end":257},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"562"},{"id":"A2","pred":"db_id","subj":"T2","obj":"562"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

Test-Species-PubDictionaries-PubMedBERT

GlyCosmos15-Glycan

{"project":"GlyCosmos15-Glycan","denotations":[{"id":"T1","span":{"begin":0,"end":7},"obj":"Glycan"},{"id":"T2","span":{"begin":451,"end":454},"obj":"Glycan"},{"id":"T3","span":{"begin":1014,"end":1023},"obj":"Glycan"},{"id":"T4","span":{"begin":1100,"end":1107},"obj":"Glycan"}],"attributes":[{"id":"A1","pred":"glycosmos_id","subj":"T1","obj":"https://glycosmos.org/glycans/show/G15541SE"},{"id":"A5","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G15541SE"},{"id":"A2","pred":"glycosmos_id","subj":"T2","obj":"https://glycosmos.org/glycans/show/ G84224TW"},{"id":"A6","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G84224TW"},{"id":"A3","pred":"glycosmos_id","subj":"T3","obj":"https://glycosmos.org/glycans/show/G66481II"},{"id":"A7","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G66481II"},{"id":"A4","pred":"glycosmos_id","subj":"T4","obj":"https://glycosmos.org/glycans/show/G15541SE"},{"id":"A8","pred":"image","subj":"T4","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G15541SE"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

Glycan-GlyCosmos

{"project":"Glycan-GlyCosmos","denotations":[{"id":"T1","span":{"begin":0,"end":7},"obj":"Glycan"},{"id":"T2","span":{"begin":1014,"end":1023},"obj":"Glycan"},{"id":"T3","span":{"begin":1100,"end":1107},"obj":"Glycan"}],"attributes":[{"id":"A1","pred":"glycosmos_id","subj":"T1","obj":"https://glycosmos.org/glycans/show/G15541SE"},{"id":"A4","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G15541SE"},{"id":"A2","pred":"glycosmos_id","subj":"T2","obj":"https://glycosmos.org/glycans/show/G66481II"},{"id":"A5","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G66481II"},{"id":"A3","pred":"glycosmos_id","subj":"T3","obj":"https://glycosmos.org/glycans/show/G15541SE"},{"id":"A6","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G15541SE"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

GlyCosmos15-CL

{"project":"GlyCosmos15-CL","denotations":[{"id":"T1","span":{"begin":1888,"end":1893},"obj":"Cell"}],"attributes":[{"id":"A1","pred":"cl_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL:0004124"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

GlyCosmos15-Taxon

{"project":"GlyCosmos15-Taxon","denotations":[{"id":"T1","span":{"begin":36,"end":52},"obj":"Organism"},{"id":"T2","span":{"begin":241,"end":257},"obj":"Organism"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"562"},{"id":"A2","pred":"db_id","subj":"T2","obj":"562"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

GlyCosmos15-Sentences

{"project":"GlyCosmos15-Sentences","blocks":[{"id":"T1","span":{"begin":0,"end":53},"obj":"Sentence"},{"id":"T2","span":{"begin":54,"end":175},"obj":"Sentence"},{"id":"T3","span":{"begin":176,"end":358},"obj":"Sentence"},{"id":"T4","span":{"begin":359,"end":606},"obj":"Sentence"},{"id":"T5","span":{"begin":607,"end":805},"obj":"Sentence"},{"id":"T6","span":{"begin":806,"end":1602},"obj":"Sentence"},{"id":"T7","span":{"begin":1603,"end":1829},"obj":"Sentence"},{"id":"T8","span":{"begin":1830,"end":2261},"obj":"Sentence"},{"id":"T9","span":{"begin":2262,"end":2264},"obj":"Sentence"},{"id":"T10","span":{"begin":2265,"end":2377},"obj":"Sentence"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

GlyCosmos15-UBERON

{"project":"GlyCosmos15-UBERON","denotations":[{"id":"T1","span":{"begin":71,"end":75},"obj":"Body_part"},{"id":"T2","span":{"begin":496,"end":504},"obj":"Body_part"},{"id":"T3","span":{"begin":528,"end":532},"obj":"Body_part"},{"id":"T4","span":{"begin":540,"end":548},"obj":"Body_part"},{"id":"T5","span":{"begin":659,"end":663},"obj":"Body_part"},{"id":"T6","span":{"begin":1676,"end":1683},"obj":"Body_part"}],"attributes":[{"id":"A1","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/UBERON_0008915"},{"id":"A2","pred":"uberon_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/UBERON_0000094"},{"id":"A3","pred":"uberon_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/UBERON_0001093"},{"id":"A4","pred":"uberon_id","subj":"T4","obj":"http://purl.obolibrary.org/obo/UBERON_0000094"},{"id":"A5","pred":"uberon_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/UBERON_0008915"},{"id":"A6","pred":"uberon_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/UBERON_0004111"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

NCBITAXON

{"project":"NCBITAXON","denotations":[{"id":"T1","span":{"begin":36,"end":52},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":241,"end":257},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"562"},{"id":"A2","pred":"db_id","subj":"T2","obj":"562"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

Anatomy-UBERON

{"project":"Anatomy-UBERON","denotations":[{"id":"T1","span":{"begin":71,"end":75},"obj":"Body_part"},{"id":"T2","span":{"begin":496,"end":504},"obj":"Body_part"},{"id":"T5","span":{"begin":528,"end":532},"obj":"Body_part"},{"id":"T6","span":{"begin":540,"end":548},"obj":"Body_part"},{"id":"T9","span":{"begin":659,"end":663},"obj":"Body_part"},{"id":"T10","span":{"begin":1676,"end":1683},"obj":"Body_part"},{"id":"T11","span":{"begin":1874,"end":1887},"obj":"Body_part"}],"attributes":[{"id":"A1","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/UBERON_0008915"},{"id":"A2","pred":"uberon_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/GO_0016020"},{"id":"A3","pred":"uberon_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/UBERON_0000094"},{"id":"A4","pred":"uberon_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/UBERON_0000158"},{"id":"A5","pred":"uberon_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/UBERON_0001093"},{"id":"A6","pred":"uberon_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/GO_0016020"},{"id":"A7","pred":"uberon_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/UBERON_0000094"},{"id":"A8","pred":"uberon_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/UBERON_0000158"},{"id":"A9","pred":"uberon_id","subj":"T9","obj":"http://purl.obolibrary.org/obo/UBERON_0008915"},{"id":"A10","pred":"uberon_id","subj":"T10","obj":"http://purl.obolibrary.org/obo/UBERON_0004111"},{"id":"A11","pred":"uberon_id","subj":"T11","obj":"http://purl.obolibrary.org/obo/GO_0016020"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}

CL-cell

{"project":"CL-cell","denotations":[{"id":"T1","span":{"begin":1888,"end":1893},"obj":"Cell"}],"attributes":[{"id":"A1","pred":"cl_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL:0004124"}],"text":"Lactose-H+(-OH) transport system of Escherichia coli. Multistate gated pore model based on half-sites stoichiometry for high-affinity substrate binding in a symmetrical dimer.\nA model is proposed for the D-galactoside-H+(-OH) transporter of Escherichia coli that accounts for essentially all the experimental observations established for this system to date. In this model, the functional unit is postulated to be a dimer (consisting of two copies of lac Y-specified polypeptide) which spans the membrane with a 2-fold symmetry axis in the membrane plane (Lancaster, J.R. (1978) J. Theor. Biol. 75, 35-50). The functional dimer is assumed to possess a single pore flanked by an inner gate (gi) and an outer gate (go) and encompassing two oppositely oriented galactoside binding sites, designated m and mu. When go is open and gi is closed under non-energized conditions, binding site m adopts a configuration defined as State A (i.e., moA) exhibiting high affinity toward Class Ga galactosides (thiodigalactoside, melibiose, alpha-p-nitrophenygalactoside) but low affinity for Class Gb galactosides (lactose, beta-o-nitrophenylgalactoside, beta-isopropylthiogalactoside), whereas binding site mu adopts State B (i.e., muoB) displaying relatively high affinity toward Class Gb galactosides but comparatively low affinity for Class Ga galactosides; further, each moA : muoB dimer contains one thiol group whose reaction with N-ethylmaleimide inactivates the transporter unless blocked by galactoside binding at site moA, while the second homologous thiol of the dimer is unreactive toward thiol reagents. Translocation of the moA : muoB dimer involves closing of go followed by opening of gi, and causes the two thiols (as well as sites m and mu) to interchange roles in a symmetrical fashion: moA : muoB in equilibrium miB : muiA. In the presence of a substantial (negative) transmembrane delta potential of muH+, the m : mu dimer is postulated to undergo an electrogenic protein conformation change to a second form, *(m : mu), in which both sites m and mu possess low affinity toward internal Class Gb substrates; galactoside transport in both m : mu and *(m : mu) is assumed to be coupled to H+-symport (-OH-antiport) with a stoichiometry of approximately 1 : 1. Finally, five characteristic predictions of the half-sites model are outlined for further tests of its validity."}