Stimulatory effect of xenobiotics on oxidative electron transport of chemolithotrophic nitrifying bacteria used as biosensing element

Andrzej Woznica; Agnieszka Nowak; Przemyslaw Ziemski; Mirosław Kwasniewski; Tytus Bernas

doi:10.1371/journal.pone.0053484

Stimulatory effect of xenobiotics on oxidative electron transport of chemolithotrophic nitrifying bacteria used as biosensing element

PLoS One. 2013;8(1):e53484. doi: 10.1371/journal.pone.0053484. Epub 2013 Jan 9.

Authors

Andrzej Woznica¹, Agnieszka Nowak, Przemyslaw Ziemski, Mirosław Kwasniewski, Tytus Bernas

Affiliation

¹ Department of Biochemistry, Faculty of Biology and Environmental Protection, University of Silesia, Katowice, Poland. andrzej.woznica@us.edu.pl

Abstract

Electron transport chain (ETCh) of ammonium (AOB) and nitrite oxidizing bacteria (NOB) participates in oxidation of ammonium to nitrate (nitrification). Operation of ETCh may be perturbed by a range of water-soluble xenobiotics. Therefore, consortia of nitrifying bacteria may be used as a biosensor to detect water contamination. A surprising feature of this system is an increase of oxygen consumption, detected in the presence of certain inhibitors of ETCh. Thus, to shed light on the mechanism of this effect (and other differences between inhibitors) we monitored separately respiration of the bacteria of the first (AOB - Nitrosomonas) and second (NOB -Nitrobacter) stages of nitrification. Furthermore, we measured plasma membrane potential and the level of reduction of NAD(P)H. We propose a novel model of ETCh in NOB to explain the role of reverse electron transport in the stimulation of oxygen consumption (previously attributed to hormesis).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Azides / pharmacology
Bacteria / drug effects
Bacteria / metabolism*
Biosensing Techniques*
Cell Membrane / drug effects
Cell Membrane / metabolism
Chemoautotrophic Growth / drug effects*
Cyanides / pharmacology
Dicumarol / pharmacology
Electron Transport / drug effects
Membrane Potentials / drug effects
Models, Biological
NADP / metabolism
Nitrification / drug effects*
Nitrites / metabolism
Oxidation-Reduction / drug effects
Oxygen Consumption / drug effects
Quaternary Ammonium Compounds / metabolism
Quinacrine / pharmacology
Xenobiotics / pharmacology*

Substances

Azides
Cyanides
Nitrites
Quaternary Ammonium Compounds
Xenobiotics
NADP
Dicumarol
Quinacrine

Grants and funding

This work was supported by the UE Innovate Economy Operational Programme, Priority 1 “Research and development of modern technologies”, Subaction 1.1.2 “An integrated system supporting the management and protection of the water reservoir”, Project number: POIG 01.01.02-24-078/09 (AW) and by the Polish Ministry for Science and Higher Education (MNiSW) grant Nr N N301 463834 (TB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.