Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?

Rhodanese from normal individuals' and acute intermittent porphyria (AIP) patients' red blood cells (RBC) was purified 134-fold, with a final yield of 20%. Normal and AIP RBC rhodanese exhibited practically the same chromatographic behaviour and also an optimum pH around 9.3. Kinetic studi...

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Detalles Bibliográficos
Autores principales: Vazquez, E., Buzaleh, A.M., Wider, E., Batlle, A.
Formato: JOUR
Materias:
5 aminolevulinate synthase
cystine
thiocyanic acid
thiosulfate
thiosulfate sulfurtransferase
unclassified drug
blood and hemopoietic system
chromatography
cytochemistry
cytology
drug efficacy
erythrocyte
human
human cell
porphyria
priority journal
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_03056651_v14_n10_p999_Vazquez
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id todo:paper_03056651_v14_n10_p999_Vazquez
record_format dspace
spelling todo:paper_03056651_v14_n10_p999_Vazquez2023-10-03T15:21:53Z Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias? Vazquez, E. Buzaleh, A.M. Wider, E. Batlle, A. 5 aminolevulinate synthase cystine thiocyanic acid thiosulfate thiosulfate sulfurtransferase unclassified drug blood and hemopoietic system chromatography cytochemistry cytology drug efficacy erythrocyte human human cell porphyria priority journal Rhodanese from normal individuals' and acute intermittent porphyria (AIP) patients' red blood cells (RBC) was purified 134-fold, with a final yield of 20%. Normal and AIP RBC rhodanese exhibited practically the same chromatographic behaviour and also an optimum pH around 9.3. Kinetic studies from normal RBC rhodanese showed substrate inhibition at high thiosulphate and cyanide concentration, while results obtained for the AIP RBC rhodanese showed substrate inhibition at high cyanide concentrations, but no inhibition at high thiosulphate concentration. Vmax and Km were similar for normal and AIP rhodanese when cyanide was the variable substrate, but those parameters differed when thiosulphate varied. On the basis of these findings it is postulated that in AIP, as a consequence of reduced affinity of rhodanese for thiosulphate, cystine trisulphide, the ALA-S activator and sulphur donor substrate for rhodanese, would not be acted on or degraded, remaining in higher concentrations than normal. As a result the activity of ALA-S would be increased, failing to operate the rhodanese control mechanism. Fil:Vazquez, E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Buzaleh, A.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Batlle, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_03056651_v14_n10_p999_Vazquez
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic 5 aminolevulinate synthase
cystine
thiocyanic acid
thiosulfate
thiosulfate sulfurtransferase
unclassified drug
blood and hemopoietic system
chromatography
cytochemistry
cytology
drug efficacy
erythrocyte
human
human cell
porphyria
priority journal
spellingShingle 5 aminolevulinate synthase
cystine
thiocyanic acid
thiosulfate
thiosulfate sulfurtransferase
unclassified drug
blood and hemopoietic system
chromatography
cytochemistry
cytology
drug efficacy
erythrocyte
human
human cell
porphyria
priority journal
Vazquez, E.
Buzaleh, A.M.
Wider, E.
Batlle, A.
Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?
topic_facet 5 aminolevulinate synthase
cystine
thiocyanic acid
thiosulfate
thiosulfate sulfurtransferase
unclassified drug
blood and hemopoietic system
chromatography
cytochemistry
cytology
drug efficacy
erythrocyte
human
human cell
porphyria
priority journal
description Rhodanese from normal individuals' and acute intermittent porphyria (AIP) patients' red blood cells (RBC) was purified 134-fold, with a final yield of 20%. Normal and AIP RBC rhodanese exhibited practically the same chromatographic behaviour and also an optimum pH around 9.3. Kinetic studies from normal RBC rhodanese showed substrate inhibition at high thiosulphate and cyanide concentration, while results obtained for the AIP RBC rhodanese showed substrate inhibition at high cyanide concentrations, but no inhibition at high thiosulphate concentration. Vmax and Km were similar for normal and AIP rhodanese when cyanide was the variable substrate, but those parameters differed when thiosulphate varied. On the basis of these findings it is postulated that in AIP, as a consequence of reduced affinity of rhodanese for thiosulphate, cystine trisulphide, the ALA-S activator and sulphur donor substrate for rhodanese, would not be acted on or degraded, remaining in higher concentrations than normal. As a result the activity of ALA-S would be increased, failing to operate the rhodanese control mechanism.
format JOUR
author Vazquez, E.
Buzaleh, A.M.
Wider, E.
Batlle, A.
author_facet Vazquez, E.
Buzaleh, A.M.
Wider, E.
Batlle, A.
author_sort Vazquez, E.
title Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?
title_short Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?
title_full Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?
title_fullStr Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?
title_full_unstemmed Reduced thiosulphate affinity for erythrocyte rhodanese: An explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?
title_sort reduced thiosulphate affinity for erythrocyte rhodanese: an explanation for increased δ-aminolevulinic synthetase activity in some porphyrias?
url http://hdl.handle.net/20.500.12110/paper_03056651_v14_n10_p999_Vazquez
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AT buzaleham reducedthiosulphateaffinityforerythrocyterhodaneseanexplanationforincreaseddaminolevulinicsynthetaseactivityinsomeporphyrias
AT widere reducedthiosulphateaffinityforerythrocyterhodaneseanexplanationforincreaseddaminolevulinicsynthetaseactivityinsomeporphyrias
AT batllea reducedthiosulphateaffinityforerythrocyterhodaneseanexplanationforincreaseddaminolevulinicsynthetaseactivityinsomeporphyrias
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