Catalases are NAD(P)H-dependent tellurite reductases

Vista sencilla de ítem
dc.contributor.authorCalderón, I.
dc.contributor.authorArenas, F.
dc.contributor.authorPérez, J.
dc.contributor.authorFuentes, D.
dc.contributor.authorAraya, M.
dc.contributor.authorSaavedra, C.
dc.contributor.authorTantaleán, J.
dc.contributor.authorPichuantes, S.
dc.contributor.authorYouderian, P.
dc.contributor.authorVásquez, C.
dc.date.accessioned2023-03-10T15:38:04Z
dc.date.available2023-03-10T15:38:04Z
dc.date.issued2006-12
dc.descriptionIndexación: Scopus.
dc.description.abstractReactive oxygen species damage intracellular targets and are implicated in cancer, genetic disease, mutagenesis, and aging. Catalases are among the key enzymatic defenses against one of the most physiologically abundant reactive oxygen species, hydrogen peroxide. The well-studied, heme-dependent catalases accelerate the rate of the dismutation of peroxide to molecular oxygen and water with near kinetic perfection. Many catalases also bind the cofactors NADPH and NADH tenaciously, but, surprisingly, NAD(P)H is not required for their dismutase activity. Although NAD(P)H protects bovine catalase against oxidative damage by its peroxide substrate, the catalytic role of the nicotinamide cofactor in the function of this enzyme has remained a biochemical mystery to date. Anions formed by heavy metal oxides are among the most highly reactive, natural oxidizing agents. Here, we show that a natural isolate of Staphylococcus epidermidis resistant to tellurite detoxifies this anion thanks to a novel activity of its catalase, and that a subset of both bacterial and mammalian catalases carry out the NAD(P)H-dependent reduction of soluble tellurite ion (TeO32-) to the less toxic, insoluble metal, tellurium (Te°), in vitro. An Escherichia colimutant defective in the KatG catalase/peroxidase is sensitive to tellurite, and expression of the S. epidermidis catalase gene in a heterologous E. coli host confers increased resistance to tellurite as well as to hydrogen peroxide in vivo, arguing that S. epidermidis catalase provides a physiological line of defense against both of these strong oxidizing agents. Kinetic studies reveal that bovine catalase reduces tellurite with a low Michaelis-Menten constant, a result suggesting that tellurite is among the natural substrates of this enzyme. The reduction of tellurite by bovine catalase occurs at the expense of producing the highly reactive superoxide radical.es
dc.description.urihttps://journals.plos.org/plosone/article?id=10.1371/journal.pone.0000070
dc.identifier.citationPLoS ONE, Volume 1, Issue 120, December 2006, Article number e70es
dc.identifier.doi10.1371/journal.pone.0000070
dc.identifier.issn1932-6203
dc.identifier.urihttps://repositorio.unab.cl/xmlui/handle/ria/47483
dc.language.isoenes
dc.publisherPublic Library of Sciencees
dc.rights.licenseAttribution 2.0 Generic (CC BY 2.0)
dc.rights.urihttps://journals.plos.org/plosone/s/journal-information#loc-open-access
dc.subjectTellurous Acides
dc.subjectTelluriaes
dc.subjectTellurite Reductasees
dc.subjectAmino Acid Sequencees
dc.subjectCatalasees
dc.subjectCattlees
dc.subjectDrug Resistancees
dc.subjectBacteriales
dc.subjectEscherichia colies
dc.subjectGeneses
dc.subjectKineticses
dc.subjectLiveres
dc.titleCatalases are NAD(P)H-dependent tellurite reductaseses
dc.typeArtículoes
Archivos
Bloque original
Mostrando 1 - 1 de 1
No hay miniatura disponible
Nombre:
Calderon_Catalases Are NAD(P)H-Dependent Tellurite Reductases.pdf
Tamaño:
181.04 KB
Formato:
Adobe Portable Document Format
Descripción:
TEXTO COMPLETO EN INGLES
Descargar
Bloque de licencias
Mostrando 1 - 1 de 1
No hay miniatura disponible
Nombre:
license.txt
Tamaño:
1.71 KB
Formato:
Item-specific license agreed upon to submission
Descripción:
Descargar
Colecciones
FCE - Artículos de Revista