RT Journal Article
T1 The NtrYX Two-Component System of Paracoccus denitrificans Is Required for the Maintenance of Cellular Iron Homeostasis and for a Complete Denitrification under Iron-Limited Conditions.
A1 Olaya-Abril, Alfonso
A1 Luque-Almagro, Victor M
A1 Hidalgo-Carrillo, Jesus
A1 Chicano-Galvez, Eduardo
A1 Urbano, Francisco J
A1 Moreno-Vivian, Conrado
A1 Richardson, David J
A1 Roldan, Maria Dolores
K1 NtrYX system
K1 Paracoccus
K1 Denitrification
K1 Ferric uptake regulator
K1 Iron homeostasis
K1 Nitrate reduction
K1 Nitrite reductase
K1 Nitrous oxide reductase
AB Denitrification consists of the sequential reduction of nitrate to nitrite, nitric oxide, nitrous oxide, and dinitrogen. Nitrous oxide escapes to the atmosphere, depending on copper availability and other environmental factors. Iron is also a key element because many proteins involved in denitrification contain iron-sulfur or heme centers. The NtrYX two-component regulatory system mediates the responses in a variety of metabolic processes, including denitrification. A quantitative proteomic analysis of a Paracoccus denitrificans NtrY mutant grown under denitrifying conditions revealed the induction of different TonB-dependent siderophore transporters and proteins related to iron homeostasis. This mutant showed lower intracellular iron content than the wild-type strain, and a reduced growth under denitrifying conditions in iron-limited media. Under iron-rich conditions, it releases higher concentrations of siderophores and displayes lower nitrous oxide reductase (NosZ) activity than the wild-type, thus leading to nitrous oxide emission. Bioinformatic and qRT-PCR analyses revealed that NtrYX is a global transcriptional regulatory system that responds to iron starvation and, in turn, controls expression of the iron-responsive regulators fur, rirA, and iscR, the denitrification regulators fnrP and narR, the nitric oxide-responsive regulator nnrS, and a wide set of genes, including the cd1-nitrite reductase NirS, nitrate/nitrite transporters and energy electron transport proteins.
PB MDPI
YR 2022
FD 2022-08-12
LK http://hdl.handle.net/10668/21189
UL http://hdl.handle.net/10668/21189
LA en
NO Olaya-Abril A, Luque-Almagro VM, Hidalgo-Carrillo J, Chicano-Gálvez E, Urbano FJ, Moreno-Vivián C, et al.  The NtrYX Two-Component System of Paracoccus denitrificans Is Required for the Maintenance of Cellular Iron Homeostasis and for a Complete Denitrification under Iron-Limited Conditions. Int J Mol Sci. 2022 Aug 15;23(16):9172
DS RISalud
RD Apr 17, 2025