Dataset Information

Metalloid Reductase of Pseudomonas moravenis Stanleyae Conveys Nanoparticle Mediated Metalloid Tolerance.

ABSTRACT: A glutathione reductase (GSHR)-like enzyme in Pseudomonas moraviensis stanleyae was previously implicated as underlying the bacterium's remarkable SeO₃ ^2- tolerance. Herein, this enzyme is sequenced, recombinantly expressed, and fully characterized. The enzyme is highly adapted for selenodiglutathione substrates (K _m = 336 μM) compared to oxidized glutathione (K _m = 8.22 mM). The recombinant expression of this enzyme in the laboratory strains of Escherichia coli conveys a 10-fold increase in IC₉₀ for SeO₃ ^2-. Moreover, selenium nanoparticles are observed when the enzyme is overexpressed in the cells exposed to SeO₃ ^2-, but not in the corresponding no-enzyme controls. The analyses of the structural homology models of the enzyme reveal changes in the parts of the enzyme associated with product release, which may underlie the Se substrate specialization. Combined, the observations of adaptation to Se reduction over oxidized glutathione reduction as well as the portability of this nanoparticle-mediated SeO₃ ^2- tolerance into other cell lines suggest that the P. moraviensis GSHR may be better described as a GSHR-like metalloid reductase.

SUBMITTER: Nemeth R

PROVIDER: S-EPMC6275949 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Metalloid Reductase of Pseudomonas moravenis Stanleyae Conveys Nanoparticle Mediated Metalloid Tolerance.

Nemeth Richard R Neubert Mackenzie M Butz Zachary J ZJ Ni Thomas W TW Ackerson Christopher J CJ

ACS omega 20181105 11

A glutathione reductase (GSHR)-like enzyme in Pseudomonas moraviensis stanleyae was previously implicated as underlying the bacterium's remarkable SeO3 2- tolerance. Herein, this enzyme is sequenced, recombinantly expressed, and fully characterized. The enzyme is highly adapted for selenodiglutathione substrates (K m = 336 μM) compared to oxidized glutathione (K m = 8.22 mM). The recombinant expression of this enzyme in the laborat ...[more]

PMID: 30533575

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Dataset Information

Metalloid Reductase of Pseudomonas moravenis Stanleyae Conveys Nanoparticle Mediated Metalloid Tolerance.

Publications

Metalloid Reductase of <i>Pseudomonas moravenis</i> Stanleyae Conveys Nanoparticle Mediated Metalloid Tolerance.

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