The terminal oxidases of <i>Paracoccus denitrificans</i>

Gier, Jan‐Willem L. de; Lübben, Mathias; Reijnders, W. N. M.; Tipker, Corinne A.; Slotboom, Dirk-Jan; Spanning, Rob J.M. van; Stouthamer, A. H.; Oost, John van der

doi:10.1111/j.1365-2958.1994.tb00414.x

Cited by 119 publications

(87 citation statements)

References 65 publications

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“…Cytochrome cbb 3 is widely expressed in different bacteria, where its very high affinity for O 2 allows growth in microaerobic conditions. A low proton-pumping efficiency reported for both intact cells (8,12) and proteoliposomes inlaid with the cbb 3 -type enzyme (11,13) has spurred speculations that this is the result of organismal adaptation to microaerobic environments. Here, we have shown that the observations of low proton-pumping stoichiometries in both cells and proteoliposomes have, at least in part, been the result of technical difficulties, as well as the extraordinary thermodynamic property of the active heme-copper site in the cbb 3 -type enzymes.…”

Section: Discussionmentioning

confidence: 99%

Mechanistic stoichiometry of proton translocation by cytochrome cbb ₃

Rauhamäki

Bloch²,

Wikström³

2012

Proc. Natl. Acad. Sci. U.S.A.

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Cytochrome cbb 3 belongs to the superfamily of respiratory hemecopper oxidases that couple the reduction of molecular oxygen to proton translocation across the bacterial or mitochondrial membrane. The cbb 3 -type enzymes are found only in bacteria, and are both structurally and functionally the most distant from their mitochondrial counterparts. The mechanistic H + /e − stoichiometry of proton translocation in these cbb 3 -type cytochrome c oxidases has remained controversial. A stoichiometric efficiency of only one-half that of the mitochondrial aa 3 -type enzyme was recently proposed to be related to adaptation of the organism to microaerobic environments. Here, proton translocation by the Rhodobacter sphaeroides enzyme was studied using purified cytochrome cbb 3 reconstituted into liposomes. An H + /e − stoichiometry of proton translocation close to unity was observed using the oxygen pulse method, but solely in conditions in which the vast majority of the enzyme was fully reduced in the anaerobic state before the O 2 pulse. These data were compared with results using whole cells or spheroplasts, and the discrepancies in the literature data were discussed. Our results suggest that a proton-pumping efficiency of 1 H + /e − may be achieved using the single-proton uptake pathway identified in the structure of cytochrome cbb 3 . The mechanism of proton pumping thus differs from that of the aa 3 -type oxidases of mitochondria and bacteria.cell respiration | proton pumping

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Section: Discussionmentioning

confidence: 99%

Mechanistic stoichiometry of proton translocation by cytochrome cbb ₃

Rauhamäki

Bloch²,

Wikström³

2012

Proc. Natl. Acad. Sci. U.S.A.

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“…In addition, however, it has been demonstrated that Paracoccus expresses two distinct respiratory branches, in which electrons are directed to three distinct types of heme-copper oxidases: a cytochrome c oxidase (cbb3) and a quinol oxidase (bb3) De Gier et al, 1994 (Fig. lb).…”

Section: The Aerobic Respiratory Networkmentioning

confidence: 99%

Regulation of oxidative phosphorylation: The flexible respiratory network ofParacoccus denitrificans

Spanning

Boer

Reijnders

et al. 1995

J Bioenerg Biomembr

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General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Download date: 12 May 2018Journal of Bioenergetics and Biomembranes, Vol. 27, No. 5, 1995 Received May 29, 1995 Paracoccus denitrificans is a facultative anaerobic bacterium that has the capacity to adjust its metabolic infrastructure, quantitatively and/or qualitatively, to the prevailing growth condition. In this bacterium the relative activity of distinct catabolic pathways is subject to a hierarchical control. In the presence of oxygen the aerobic respiration, the most efficient way of electron transfer-linked phosphorylation, has priority. At high oxygen tensions P. denitrificans synthesizes an oxidase with a relatively low affinity for oxygen, whereas under oxygen limitation a high-affinity oxidase appears specifically induced. During anaerobiosis, the pathways with lower free energy-transducing efficiency are induced. In the presence of nitrate, the expression of a number of dehydrogenases ensures the continuation of oxidative pbosphorylation via denitrification. After identification of the structural components that are involved in both the aerobic and the anaerobic respiratory networks of P. denitrificans, the intriguing next challenge is to get insight in its regulation. Two transcription regulators have recently been demonstrated to be involved in the expression of a number of aerobic and/or anaerobic respiratory complexes in P. denitrificans. Understanding of the regulation machinery is beginning to emerge and promises much excitement in discovery.KEY WORDS: Respiratory network; multiple oxidases; denitrification; gene regulation; FNR; Paracoccus denitrificans; Escherichia coli. ~TRODUCTIONThe ultimate goal of living organisms is to contribute to a continued existence of their species by means of survival and reproduction. In unicellular organisms, the ability to survive depends on the cell's potential to adapt its metabolism to the available carbon and free-energy sources in its natural habitat, ensuring maintenance and growth. The more such an environment is subject to fluctuations in the supply of these substrates, the higher the demands that are made upon the potential of the cell to adjust its metabolic properties. A profound example of this flexibility is the process of bacterial respiration...

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“…denitrificans is able to reduce molecular oxygen at a wide range of oxygen concentrations. This flexibility is the result of its potential to synthesize three types of terminal oxidase (9,10,32,33,35), which all belong to the superfamily of heme copper oxidases (15,38,44). The one that is most expressed at atmospheric oxygen concentrations is the aa 3 -type cytochrome c oxidase, which has a relatively low affinity for oxygen (31,36).…”

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confidence: 99%

“…The second type of oxidase is the cbb 3 -type cytochrome c oxidase, which has a relatively high affinity for oxygen and which is increasingly synthesized at decreasing oxygen concentrations (10,31). The third type of oxidase is a ba 3 -type quinol oxidase, which is the counterpart of the bo 3 -type quinol oxidase found in Escherichia coli (8,35). The ba 3 -type oxidase receives electrons from ubiquinol, is expressed and increasingly active under conditions that give rise to high reduction levels of the Q-pool, and apparently serves to prevent that by rapidly transferring electrons from ubiquinol to oxygen (27).…”

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confidence: 99%

Cytochromes c ₅₅₀ , c ₅₅₂ , and c ₁ in the Electron Transport Network of Paracoccus denitrificans : Redundant or Subtly Different in Function?

Otten

Oost²,

Reijnders³

et al. 2001

J Bacteriol

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Paracoccus denitrificans strains with mutations in the genes encoding the cytochrome c 550 , c 552 , or c 1 and in combinations of these genes were constructed, and their growth characteristics were determined. Each mutant was able to grow heterotrophically with succinate as the carbon and free-energy source, although their specific growth rates and maximum cell numbers fell variably behind those of the wild type. Maximum cell numbers and rates of growth were also reduced when these strains were grown with methylamine as the sole free-energy source, with the triple cytochrome c mutant failing to grow on this substrate. Under anaerobic conditions in the presence of nitrate, none of the mutant strains lacking the cytochrome bc 1 complex reduced nitrite, which is cytotoxic and accumulated in the medium. The cytochrome c 550 -deficient mutant did denitrify provided copper was present. The cytochrome c 552 mutation had no apparent effect on the denitrifying potential of the mutant cells. The studies show that the cytochromes c have multiple tasks in electron transfer. The cytochrome bc 1 complex is the electron acceptor of the Q-pool and of amicyanin. It is also the electron donor to cytochromes c 550 and c 552 and to the cbb 3 -type oxidase. Cytochrome c 552 is an electron acceptor both of the cytochrome bc 1 complex and of amicyanin, as well as a dedicated electron donor to the aa 3 -type oxidase. Cytochrome c 550 can accept electrons from the cytochrome bc 1 complex and from amicyanin, whereas it is also the electron donor to both cytochrome c oxidases and to at least the nitrite reductase during denitrification. Deletion of the c-type cytochromes also affected the concentrations of remaining cytochromes c, suggesting that the organism is plastic in that it adjusts its infrastructure in response to signals derived from changed electron transfer routes.

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The terminal oxidases of Paracoccus denitrificans

Cited by 119 publications

References 65 publications

Mechanistic stoichiometry of proton translocation by cytochrome cbb ₃

Mechanistic stoichiometry of proton translocation by cytochrome cbb ₃

Regulation of oxidative phosphorylation: The flexible respiratory network ofParacoccus denitrificans

Cytochromes c ₅₅₀ , c ₅₅₂ , and c ₁ in the Electron Transport Network of Paracoccus denitrificans : Redundant or Subtly Different in Function?

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The terminal oxidases of Paracoccus denitrificans

Cited by 119 publications

References 65 publications

Mechanistic stoichiometry of proton translocation by cytochrome cbb 3

Mechanistic stoichiometry of proton translocation by cytochrome cbb 3

Regulation of oxidative phosphorylation: The flexible respiratory network ofParacoccus denitrificans

Cytochromes c 550 , c 552 , and c 1 in the Electron Transport Network of Paracoccus denitrificans : Redundant or Subtly Different in Function?

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Mechanistic stoichiometry of proton translocation by cytochrome cbb ₃

Mechanistic stoichiometry of proton translocation by cytochrome cbb ₃

Cytochromes c ₅₅₀ , c ₅₅₂ , and c ₁ in the Electron Transport Network of Paracoccus denitrificans : Redundant or Subtly Different in Function?