A mechanism for complementation of the sodA sodB defect in Escherichia coli by overproduction of the rbo gene product (desulfoferrodoxin) from Desulfoarculus baarsii.
J Biol Chem
; 272(41): 25573-5, 1997 Oct 10.
Article
em En
| MEDLINE
| ID: mdl-9325275
ABSTRACT
Overexpression of rbo in Escherichia coli prevents the inactivation of the [4Fe-4S]-containing fumarases that otherwise occurs in the sodA sodB strain. It similarly protects against the increased sensitivity toward H2O2, which is imposed by the lack of SOD A and SOD B. These results would be explained on the basis of scavenging of O-2 within the cells by RBO. This interpretation was supported by measurements of intracellular scavenging of O-2 by the lucigenin luminescence method. Since SOD activity could not be detected in dilute extracts, of the RBO-overexpressing sodA sodB strain, we propose that RBO catalyzes the reduction of O-2 at the expense of cellular reductants such as NAD(P)H. A similar mechanism may apply to other instances of complementation of SOD defects by non-SOD genes.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Superóxido Dismutase
/
Proteínas de Bactérias
/
Desulfovibrio
/
Ferredoxinas
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Estados Unidos