RRC ID |
52859
|
Author |
Iwasaki T, Fukazawa R, Miyajima-Nakano Y, Baldansuren A, Matsushita S, Lin MT, Gennis RB, Hasegawa K, Kumasaka T, Dikanov SA.
|
Title |
Dissection of hydrogen bond interaction network around an iron-sulfur cluster by site-specific isotope labeling of hyperthermophilic archaeal Rieske-type ferredoxin.
|
Journal |
J Am Chem Soc
|
Abstract |
The electronic structure and geometry of redox-active metal cofactors in proteins are tuned by the pattern of hydrogen bonding with the backbone peptide matrix. In this study we developed a method for selective amino acid labeling of a hyperthermophilic archaeal metalloprotein with engineered Escherichia coli auxotroph strains, and we applied this to resolve the hydrogen bond interactions with the reduced Rieske-type [2Fe-2S] cluster by two-dimensional pulsed electron spin resonance technique. Because deep electron spin-echo envelope modulation of two histidine (14)N(δ) ligands of the cluster decreased non-coordinating (15)N signal intensities via the cross-suppression effect, an inverse labeling strategy was employed in which (14)N amino acid-labeled archaeal Rieske-type ferredoxin samples were examined in an (15)N-protein background. This has directly identified Lys45 N(α) as providing the major pathway for the transfer of unpaired electron spin density from the reduced cluster by a "through-bond" mechanism. All other backbone peptide nitrogens interact more weakly with the reduced cluster. The extension of this approach will allow visualizing the three-dimensional landscape of preferred pathways for the transfer of unpaired spin density from a paramagnetic metal center onto the protein frame, and will discriminate specific interactions by a "through-bond" mechanism from interactions which are "through-space" in various metalloproteins.
|
Volume |
134(48)
|
Pages |
19731-8
|
Published |
2012-12-5
|
DOI |
10.1021/ja308049u
|
PMID |
23145461
|
PMC |
PMC3515699
|
MeSH |
Binding Sites
Escherichia coli / genetics
Ferredoxins / chemistry*
Hydrogen Bonding
Iron / chemistry*
Isotope Labeling
Models, Molecular
Oxidation-Reduction
Pyrodictiaceae / chemistry
Substrate Specificity
Sulfolobus solfataricus / chemistry
Sulfur / chemistry*
|
IF |
14.695
|
Times Cited |
14
|
Resource |
DNA material |
YM138 (RDB15943)
MS1 (RDB15944). |