A novel dimethylsulfoxide reductase family of molybdenum enzyme, Idr, is involved in iodate respiration by Pseudomonas sp. SCT.
Environ Microbiol
; 22(6): 2196-2212, 2020 06.
Article
en En
| MEDLINE
| ID: mdl-32190953
ABSTRACT
Pseudomonas sp. strain SCT is capable of using iodate (IO3 - ) as a terminal electron acceptor for anaerobic respiration. A possible key enzyme, periplasmic iodate reductase (Idr), was visualized by active staining on non-denaturing gel electrophoresis. Liquid chromatography-tandem mass spectrometry analysis revealed that at least four proteins, designated as IdrA, IdrB, IdrP1 , and IdrP2 , were involved in Idr. IdrA and IdrB were homologues of catalytic and electron transfer subunits of respiratory arsenite oxidase (Aio); however, IdrA defined a novel clade within the dimethylsulfoxide (DMSO) reductase family. IdrP1 and IdrP2 were closely related to each other and distantly related to cytochrome c peroxidase. The idr genes (idrABP 1 P 2 ) formed an operon-like structure, and their transcription was upregulated under iodate-respiring conditions. Comparative proteomic analysis also revealed that Idr proteins and high affinity terminal oxidases (Cbb3 and Cyd), various H2 O2 scavengers, and chlorite (ClO2 - ) dismutase-like proteins were expressed specifically or abundantly under iodate-respiring conditions. These results suggest that Idr is a respiratory iodate reductase, and that both O2 and H2 O2 are formed as by-products of iodate respiration. We propose an electron transport chain model of strain SCT, in which iodate, H2 O2 , and O2 are used as terminal electron acceptors.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Oxidorreductasas
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Pseudomonas
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Proteínas Periplasmáticas
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Yodatos
Idioma:
En
Revista:
Environ Microbiol
Asunto de la revista:
MICROBIOLOGIA
/
SAUDE AMBIENTAL
Año:
2020
Tipo del documento:
Article
País de afiliación:
Japón