Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants

Autores
Ballicora, M.A.; Wolosiuk, R.A.
Año de publicación
1994
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
To characterize the mechanism of chloroplast fructose‐1,6‐bisphosphatase activation, we have examined kinetic and structural changes elicited by protein perturbants and reductants. At variance with its well‐known capacity for enzyme inactivation, 150 mM sodium trichloroacetate yielded an activatable chloroplast fructose‐1,6‐bisphosphatase in the presence of 1.0 mM fructose 1,6‐bisphosphate and 0.1 mM Ca2+. Other sugar bisphosphates did not replace fructose 1,6‐bisphosphate whereas Mg2+ and Mn2+ were functional in place of Ca2+. Variations of the emission fluorescence of intrinsic fluorophores and a noncovalently bound extrinsic probe [2‐(P‐toluidinyl)naphthalene‐6‐sulfonate] indicated the presence of conformations different from the native form. A similar conclusion was drawn from the analysis of absorption spectra by means of fourth‐derivative spectrophotometry. The effect of these conformational changes on the reductive process was studied by subsequently incubating the enzyme with dithiothreitol. The reaction of chloroplast fructose‐1,6‐bisphosphatase with dithiothreitol was accelerated 13‐fold by the chaotropic anion: second‐order rate constants were 48.1 M−1· min−1 and 3.7 M−1· min−1 in the presence and in the absence of trichloroacetate, respectively. Thus, the enhancement of the reductive activation by compounds devoid of redox activity illustrated that the modification of intramolecular noncovalent interactions of chloroplast fructose‐1,6‐bisphosphatase plays an essential role in the conversion of enzyme disulfide bonds to sulfhydryl groups. In consequence, a conformational change would operate concertedly with the reduction of disulfide bridges in the light‐dependent activation mediated by the ferredoxin–thioredoxin system. Copyright © 1994, Wiley Blackwell. All rights reserved
Fil:Ballicora, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Wolosiuk, R.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fuente
Eur. J. Biochem. 1994;222(2):467-474
Materia
fructose 2,6 bisphosphatase
article
chloroplast
conformational transition
disulfide bond
enzyme inactivation
enzyme mechanism
priority journal
spinach
Cations, Divalent
Chloroplasts
Fructose-Bisphosphatase
Fructosediphosphates
Kinetics
Oxidation-Reduction
Spectrometry, Fluorescence
Spectrophotometry, Ultraviolet
Support, Non-U.S. Gov't
Trichloroacetic Acid
Vegetables
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by/2.5/ar
Repositorio
Biblioteca Digital (UBA-FCEN)
Institución
Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
OAI Identificador
paperaa:paper_00142956_v222_n2_p467_Ballicora

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oai_identifier_str paperaa:paper_00142956_v222_n2_p467_Ballicora
network_acronym_str BDUBAFCEN
repository_id_str 1896
network_name_str Biblioteca Digital (UBA-FCEN)
spelling Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbantsBallicora, M.A.Wolosiuk, R.A.fructose 2,6 bisphosphatasearticlechloroplastconformational transitiondisulfide bondenzyme inactivationenzyme mechanismpriority journalspinachCations, DivalentChloroplastsFructose-BisphosphataseFructosediphosphatesKineticsOxidation-ReductionSpectrometry, FluorescenceSpectrophotometry, UltravioletSupport, Non-U.S. Gov'tTrichloroacetic AcidVegetablesTo characterize the mechanism of chloroplast fructose‐1,6‐bisphosphatase activation, we have examined kinetic and structural changes elicited by protein perturbants and reductants. At variance with its well‐known capacity for enzyme inactivation, 150 mM sodium trichloroacetate yielded an activatable chloroplast fructose‐1,6‐bisphosphatase in the presence of 1.0 mM fructose 1,6‐bisphosphate and 0.1 mM Ca2+. Other sugar bisphosphates did not replace fructose 1,6‐bisphosphate whereas Mg2+ and Mn2+ were functional in place of Ca2+. Variations of the emission fluorescence of intrinsic fluorophores and a noncovalently bound extrinsic probe [2‐(P‐toluidinyl)naphthalene‐6‐sulfonate] indicated the presence of conformations different from the native form. A similar conclusion was drawn from the analysis of absorption spectra by means of fourth‐derivative spectrophotometry. The effect of these conformational changes on the reductive process was studied by subsequently incubating the enzyme with dithiothreitol. The reaction of chloroplast fructose‐1,6‐bisphosphatase with dithiothreitol was accelerated 13‐fold by the chaotropic anion: second‐order rate constants were 48.1 M−1· min−1 and 3.7 M−1· min−1 in the presence and in the absence of trichloroacetate, respectively. Thus, the enhancement of the reductive activation by compounds devoid of redox activity illustrated that the modification of intramolecular noncovalent interactions of chloroplast fructose‐1,6‐bisphosphatase plays an essential role in the conversion of enzyme disulfide bonds to sulfhydryl groups. In consequence, a conformational change would operate concertedly with the reduction of disulfide bridges in the light‐dependent activation mediated by the ferredoxin–thioredoxin system. Copyright © 1994, Wiley Blackwell. All rights reservedFil:Ballicora, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Wolosiuk, R.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.1994info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfhttp://hdl.handle.net/20.500.12110/paper_00142956_v222_n2_p467_BallicoraEur. J. Biochem. 1994;222(2):467-474reponame:Biblioteca Digital (UBA-FCEN)instname:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturalesinstacron:UBA-FCENenginfo:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by/2.5/ar2025-09-29T13:43:02Zpaperaa:paper_00142956_v222_n2_p467_BallicoraInstitucionalhttps://digital.bl.fcen.uba.ar/Universidad públicaNo correspondehttps://digital.bl.fcen.uba.ar/cgi-bin/oaiserver.cgiana@bl.fcen.uba.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:18962025-09-29 13:43:04.211Biblioteca Digital (UBA-FCEN) - Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturalesfalse
dc.title.none.fl_str_mv Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
title Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
spellingShingle Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
Ballicora, M.A.
fructose 2,6 bisphosphatase
article
chloroplast
conformational transition
disulfide bond
enzyme inactivation
enzyme mechanism
priority journal
spinach
Cations, Divalent
Chloroplasts
Fructose-Bisphosphatase
Fructosediphosphates
Kinetics
Oxidation-Reduction
Spectrometry, Fluorescence
Spectrophotometry, Ultraviolet
Support, Non-U.S. Gov't
Trichloroacetic Acid
Vegetables
title_short Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
title_full Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
title_fullStr Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
title_full_unstemmed Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
title_sort Enhancement of the reductive activation of chloroplast fructose‐1,6‐bisphosphatase by modulators and protein perturbants
dc.creator.none.fl_str_mv Ballicora, M.A.
Wolosiuk, R.A.
author Ballicora, M.A.
author_facet Ballicora, M.A.
Wolosiuk, R.A.
author_role author
author2 Wolosiuk, R.A.
author2_role author
dc.subject.none.fl_str_mv fructose 2,6 bisphosphatase
article
chloroplast
conformational transition
disulfide bond
enzyme inactivation
enzyme mechanism
priority journal
spinach
Cations, Divalent
Chloroplasts
Fructose-Bisphosphatase
Fructosediphosphates
Kinetics
Oxidation-Reduction
Spectrometry, Fluorescence
Spectrophotometry, Ultraviolet
Support, Non-U.S. Gov't
Trichloroacetic Acid
Vegetables
topic fructose 2,6 bisphosphatase
article
chloroplast
conformational transition
disulfide bond
enzyme inactivation
enzyme mechanism
priority journal
spinach
Cations, Divalent
Chloroplasts
Fructose-Bisphosphatase
Fructosediphosphates
Kinetics
Oxidation-Reduction
Spectrometry, Fluorescence
Spectrophotometry, Ultraviolet
Support, Non-U.S. Gov't
Trichloroacetic Acid
Vegetables
dc.description.none.fl_txt_mv To characterize the mechanism of chloroplast fructose‐1,6‐bisphosphatase activation, we have examined kinetic and structural changes elicited by protein perturbants and reductants. At variance with its well‐known capacity for enzyme inactivation, 150 mM sodium trichloroacetate yielded an activatable chloroplast fructose‐1,6‐bisphosphatase in the presence of 1.0 mM fructose 1,6‐bisphosphate and 0.1 mM Ca2+. Other sugar bisphosphates did not replace fructose 1,6‐bisphosphate whereas Mg2+ and Mn2+ were functional in place of Ca2+. Variations of the emission fluorescence of intrinsic fluorophores and a noncovalently bound extrinsic probe [2‐(P‐toluidinyl)naphthalene‐6‐sulfonate] indicated the presence of conformations different from the native form. A similar conclusion was drawn from the analysis of absorption spectra by means of fourth‐derivative spectrophotometry. The effect of these conformational changes on the reductive process was studied by subsequently incubating the enzyme with dithiothreitol. The reaction of chloroplast fructose‐1,6‐bisphosphatase with dithiothreitol was accelerated 13‐fold by the chaotropic anion: second‐order rate constants were 48.1 M−1· min−1 and 3.7 M−1· min−1 in the presence and in the absence of trichloroacetate, respectively. Thus, the enhancement of the reductive activation by compounds devoid of redox activity illustrated that the modification of intramolecular noncovalent interactions of chloroplast fructose‐1,6‐bisphosphatase plays an essential role in the conversion of enzyme disulfide bonds to sulfhydryl groups. In consequence, a conformational change would operate concertedly with the reduction of disulfide bridges in the light‐dependent activation mediated by the ferredoxin–thioredoxin system. Copyright © 1994, Wiley Blackwell. All rights reserved
Fil:Ballicora, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Wolosiuk, R.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
description To characterize the mechanism of chloroplast fructose‐1,6‐bisphosphatase activation, we have examined kinetic and structural changes elicited by protein perturbants and reductants. At variance with its well‐known capacity for enzyme inactivation, 150 mM sodium trichloroacetate yielded an activatable chloroplast fructose‐1,6‐bisphosphatase in the presence of 1.0 mM fructose 1,6‐bisphosphate and 0.1 mM Ca2+. Other sugar bisphosphates did not replace fructose 1,6‐bisphosphate whereas Mg2+ and Mn2+ were functional in place of Ca2+. Variations of the emission fluorescence of intrinsic fluorophores and a noncovalently bound extrinsic probe [2‐(P‐toluidinyl)naphthalene‐6‐sulfonate] indicated the presence of conformations different from the native form. A similar conclusion was drawn from the analysis of absorption spectra by means of fourth‐derivative spectrophotometry. The effect of these conformational changes on the reductive process was studied by subsequently incubating the enzyme with dithiothreitol. The reaction of chloroplast fructose‐1,6‐bisphosphatase with dithiothreitol was accelerated 13‐fold by the chaotropic anion: second‐order rate constants were 48.1 M−1· min−1 and 3.7 M−1· min−1 in the presence and in the absence of trichloroacetate, respectively. Thus, the enhancement of the reductive activation by compounds devoid of redox activity illustrated that the modification of intramolecular noncovalent interactions of chloroplast fructose‐1,6‐bisphosphatase plays an essential role in the conversion of enzyme disulfide bonds to sulfhydryl groups. In consequence, a conformational change would operate concertedly with the reduction of disulfide bridges in the light‐dependent activation mediated by the ferredoxin–thioredoxin system. Copyright © 1994, Wiley Blackwell. All rights reserved
publishDate 1994
dc.date.none.fl_str_mv 1994
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/20.500.12110/paper_00142956_v222_n2_p467_Ballicora
url http://hdl.handle.net/20.500.12110/paper_00142956_v222_n2_p467_Ballicora
dc.language.none.fl_str_mv eng
language eng
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/2.5/ar
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by/2.5/ar
dc.format.none.fl_str_mv application/pdf
dc.source.none.fl_str_mv Eur. J. Biochem. 1994;222(2):467-474
reponame:Biblioteca Digital (UBA-FCEN)
instname:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
instacron:UBA-FCEN
reponame_str Biblioteca Digital (UBA-FCEN)
collection Biblioteca Digital (UBA-FCEN)
instname_str Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
instacron_str UBA-FCEN
institution UBA-FCEN
repository.name.fl_str_mv Biblioteca Digital (UBA-FCEN) - Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
repository.mail.fl_str_mv ana@bl.fcen.uba.ar
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