Evidence for a band III analogue in the near-infrared absorption spectra of cytochrome c oxidase

Einarsdóttir, Ólöf; Georgiadis, Katy E.; Dawes, Timothy D.

doi:10.1016/0006-291x(92)90695-h

Cited by 12 publications

(11 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…More recently, Einarsdottir et al (1992) and Rich et al (1992) presented convincing new evidence that cytochrome a3 provides a specific absorbance at -785 nm. Einarsdottir et al (1992) also describe an absorbance feature at -710 nm that they attribute to cytochrome a. Hallen and Brzezinski (1994) reported that kinetic changes at 830 nm during the oxidation of one electronreduced cytochrome aa3 could be attributed mainly to heme absorption.…”

Section: Introductionmentioning

confidence: 96%

“…C) 1994 by the Biophysical Society 0006-3495/94/12/2493/08 $2.00 absorbance comes from CuA. More recently, Einarsdottir et al (1992) and Rich et al (1992) presented convincing new evidence that cytochrome a3 provides a specific absorbance at -785 nm. Einarsdottir et al (1992) also describe an absorbance feature at -710 nm that they attribute to cytochrome a.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Near infrared spectral changes of cytochrome aa3 during potentiometric titrations

Hendler

Harmon

Levin

1994

Biophysical Journal

View full text Add to dashboard Cite

Singular value decomposition (SVD) was used to deconvolute the spectral changes occurring in the near infrared region during potentiometric titrations of cytochrome aa3. Overall oxidized minus reduced difference spectra revealed a broad absorbance feature centered near 830 nm with an apparent Em near 250 mV. However, SVD did not isolate any spectral species with an absorbance centered near 830 nm. It was found that the spectral changes occurring in the wavelength region from 650 to 950 nm were associated mainly with cytochromes a and a3. It was concluded that the absorbance at 830 nm should not be used as an independent measure of the concentration of CuA in cytochrome aa3.

show abstract

Section: Introductionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

Near infrared spectral changes of cytochrome aa3 during potentiometric titrations

Hendler

Harmon

Levin

1994

Biophysical Journal

View full text Add to dashboard Cite

show abstract

“…However, several unresolved questions remain: Cu B reduction perturbs the 655 nm band in the oxidised enzyme [15,16] ; haem a spectral shifts occur upon inhibitory ligand binding to the binuclear centre [17] ; the reduced a 3 Cu B spectrum may include Cu B -dependent as well as haem a 3 components [18–20] ; and other minor NIR absorbance bands are present, generally attributed to ferrous haem a 3 [21–23] . Distinguishing different NIR spectral changes is thus essential to analysing oxidase function in vitro.…”

Section: Introductionmentioning

confidence: 99%

Re-evaluation of the near infrared spectra of mitochondrial cytochrome c oxidase: Implications for non invasive in vivo monitoring of tissues

Mason

Nicholls

Cooper

2014

Biochimica et Biophysica Acta (BBA) - Bioenergetics

View full text Add to dashboard Cite

We re-determined the near infrared (NIR) spectral signatures (650–980 nm) of the different cytochrome c oxidase redox centres, in the process separating them into their component species. We confirm that the primary contributor to the oxidase NIR spectrum between 700 and 980 nm is cupric CuA, which in the beef heart enzyme has a maximum at 835 nm. The 655 nm band characterises the fully oxidised haem a3/CuB binuclear centre; it is bleached either when one or more electrons are added to the binuclear centre or when the latter is modified by ligands. The resulting ‘perturbed’ binuclear centre is also characterised by a previously unreported broad 715–920 nm band. The NIR spectra of certain stable liganded species (formate and CO), and the unstable oxygen reaction compounds P and F, are similar, suggesting that the latter may resemble the stable species electronically. Oxidoreduction of haem a makes no contribution either to the 835 nm maximum or the 715 nm band. Our results confirm the ability of NIRS to monitor the CuA centre of cytochrome oxidase activity in vivo, although noting some difficulties in precise quantitative interpretations in the presence of perturbations of the haem a3/CuB binuclear centre.

show abstract

“…. 20 The addition of carbon monoxide to the reduced enzyme causes a blue shift from 785 to 760 nm in the difference spectrum, and the photodissociation of CO results in a reversion of the band from 760 to 784 nm. 17 The far-red maximum in the action spectra ( Fig.…”

mentioning

confidence: 99%

Exact Action Spectra for Cellular Responses Relevant to Phototherapy

Karu

Kolyakov

2005

Photomedicine and Laser Surgery

507

322

View full text Add to dashboard Cite

show abstract

Evidence for a band III analogue in the near-infrared absorption spectra of cytochrome c oxidase

Cited by 12 publications

References 17 publications

Near infrared spectral changes of cytochrome aa3 during potentiometric titrations

Near infrared spectral changes of cytochrome aa3 during potentiometric titrations

Re-evaluation of the near infrared spectra of mitochondrial cytochrome c oxidase: Implications for non invasive in vivo monitoring of tissues

Exact Action Spectra for Cellular Responses Relevant to Phototherapy

Contact Info

Product

Resources

About