A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin
The absorption and resonance Raman spectra and the azide binding kinetics of ferric horse heart myoglobin (Mb) and mini myoglobin (a chemically truncated form of horse heart Mb containing residues 32–139) have been compared. The steady-state spectra show that an additional six-coordinated low-spin f...
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ftpubmed:oai:pubmedcentral.nih.gov:1959552 2023-05-15T18:26:39+02:00 A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin De Sanctis, Giampiero Petrella, Giovanni Ciaccio, Chiara Feis, Alessandro Smulevich, Giulietta Coletta, Massimo 2007-09-15 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1959552 http://www.ncbi.nlm.nih.gov/pubmed/17496043 https://doi.org/10.1529/biophysj.106.098764 en eng Biophysical Society http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1959552 http://www.ncbi.nlm.nih.gov/pubmed/17496043 http://dx.doi.org/10.1529/biophysj.106.098764 Copyright © 2007, Biophysical Society Proteins Text 2007 ftpubmed https://doi.org/10.1529/biophysj.106.098764 2013-09-01T01:19:25Z The absorption and resonance Raman spectra and the azide binding kinetics of ferric horse heart myoglobin (Mb) and mini myoglobin (a chemically truncated form of horse heart Mb containing residues 32–139) have been compared. The steady-state spectra show that an additional six-coordinated low-spin form (not present in entire horse heart Mb, which is purely six-coordinated high spin) predominates in mini Mb. The distal histidine is possibly the sixth ligand in this species. The presence of two species corresponds to a kinetic biphasicity for mini Mb that is not observed for horse heart Mb. Azide binds to horse heart Mb much more slowly than to sperm whale Mb. This difference may result from a sterically hindered distal pocket in horse heart Mb. In both cases, the rate constants level off at high azide concentrations, implying the existence of a rate-limiting step (likely referable to the dissociation of the axial sixth ligand). The faster rate constant of mini Mb is similar to that of sperm whale Mb, whereas the slower one is similar to that of entire horse heart Mb. Text Sperm whale PubMed Central (PMC) Biophysical Journal 93 6 2135 2142 |
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Proteins |
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Proteins De Sanctis, Giampiero Petrella, Giovanni Ciaccio, Chiara Feis, Alessandro Smulevich, Giulietta Coletta, Massimo A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin |
topic_facet |
Proteins |
description |
The absorption and resonance Raman spectra and the azide binding kinetics of ferric horse heart myoglobin (Mb) and mini myoglobin (a chemically truncated form of horse heart Mb containing residues 32–139) have been compared. The steady-state spectra show that an additional six-coordinated low-spin form (not present in entire horse heart Mb, which is purely six-coordinated high spin) predominates in mini Mb. The distal histidine is possibly the sixth ligand in this species. The presence of two species corresponds to a kinetic biphasicity for mini Mb that is not observed for horse heart Mb. Azide binds to horse heart Mb much more slowly than to sperm whale Mb. This difference may result from a sterically hindered distal pocket in horse heart Mb. In both cases, the rate constants level off at high azide concentrations, implying the existence of a rate-limiting step (likely referable to the dissociation of the axial sixth ligand). The faster rate constant of mini Mb is similar to that of sperm whale Mb, whereas the slower one is similar to that of entire horse heart Mb. |
format |
Text |
author |
De Sanctis, Giampiero Petrella, Giovanni Ciaccio, Chiara Feis, Alessandro Smulevich, Giulietta Coletta, Massimo |
author_facet |
De Sanctis, Giampiero Petrella, Giovanni Ciaccio, Chiara Feis, Alessandro Smulevich, Giulietta Coletta, Massimo |
author_sort |
De Sanctis, Giampiero |
title |
A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin |
title_short |
A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin |
title_full |
A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin |
title_fullStr |
A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin |
title_full_unstemmed |
A Comparative Study on Axial Coordination and Ligand Binding in Ferric Mini Myoglobin and Horse Heart Myoglobin |
title_sort |
comparative study on axial coordination and ligand binding in ferric mini myoglobin and horse heart myoglobin |
publisher |
Biophysical Society |
publishDate |
2007 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1959552 http://www.ncbi.nlm.nih.gov/pubmed/17496043 https://doi.org/10.1529/biophysj.106.098764 |
genre |
Sperm whale |
genre_facet |
Sperm whale |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1959552 http://www.ncbi.nlm.nih.gov/pubmed/17496043 http://dx.doi.org/10.1529/biophysj.106.098764 |
op_rights |
Copyright © 2007, Biophysical Society |
op_doi |
https://doi.org/10.1529/biophysj.106.098764 |
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Biophysical Journal |
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93 |
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6 |
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2135 |
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2142 |
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1766208615275823104 |