Modifications of the Aerobic Respiratory Chain of Paracoccus Denitrificans in Response to Superoxide Oxidative Stress

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F19%3A00107871" target="_blank" >RIV/00216224:14310/19:00107871 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.3390/microorganisms7120640" target="_blank" >https://doi.org/10.3390/microorganisms7120640</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/microorganisms7120640" target="_blank" >10.3390/microorganisms7120640</a>

Result language

angličtina

Original language name

Modifications of the Aerobic Respiratory Chain of Paracoccus Denitrificans in Response to Superoxide Oxidative Stress

Original language description

Paracoccus denitrificans is a strictly respiring bacterium with a core respiratory chain similar to that of mammalian mitochondria. As such, it continuously produces and has to cope with superoxide and other reactive oxygen species. In this work, the effects of artificially imposed superoxide stress on electron transport were examined. Exposure of aerobically growing cells to paraquat resulted in decreased activities of NADH dehydrogenase, succinate dehydrogenase, and N,N,N’,N’-tetramethyl-p-phenylenediamine (TMPD) oxidase. Concomitantly, the total NAD(H) pool size in cells was approximately halved, but the NADH/NAD+ ratio increased twofold, thus partly compensating for inactivation losses of the dehydrogenase. The inactivation of respiratory dehydrogenases, but not of TMPD oxidase, also took place upon treatment of the membrane fraction with xanthine/xanthine oxidase. The decrease in dehydrogenase activities could be fully rescued by anaerobic incubation of membranes in a mixture containing 2-mercaptoethanol, sulfide and ferrous iron, which suggests iron–sulfur clusters as targets for superoxide. By using cyanide titration, a stress-sensitive contribution to the total TMPD oxidase activity was identified and attributed to the cbb3-type terminal oxidase. This response (measured by both enzymatic activity and mRNA level) was abolished in a mutant defective for the FnrP transcription factor. Therefore, our results provide evidence of oxidative stress perception by FnrP.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10600 - Biological sciences

Project

<a href="/en/project/GA16-18476S" target="_blank" >GA16-18476S: Oxidative stress in denitrifying bacteria: deciphering functions of involved proteins and possible environmental impacts</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2019

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Microorganisms

ISSN

2076-2607

e-ISSN

—

Volume of the periodical

7

Issue of the periodical within the volume

12

Country of publishing house

CH - SWITZERLAND

Number of pages

12

Pages from-to

1-12

UT code for WoS article

000506646400058

EID of the result in the Scopus database

2-s2.0-85078613928