Electron paramagnetic resonance of globin proteins – a successful match between spectroscopic development and protein research

Doorslaer, Sabine Van; Cuypers, Bert

doi:10.1080/00268976.2017.1392629

Cited by 7 publications

(11 citation statements)

References 152 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A fast increase in the absorbance signal followed by a decrease in the signal intensity could possibly arise due to a fast rate of TMB oxidation by the L-PGDS/heme complex. similar to spectra observed for many globin proteins where the heme Fe(III) paramagnetic center is hexa-co-ordinated, high-spin and in an environment with rhombic symmetry (intense signal at g = 6 with a shoulder at g ∼ 7) [61,62].…”

Section: Resultssupporting

confidence: 76%

“…The presence of hexa-co-ordinate, high-spin, Fe (ІІІ) heme was further supported by the X-band continuous wave EPR (cw EPR) spectrum of L-PGDS/heme in a 1 : 1 molar ratio complex (Figure 1B). The occurrence of a strong signal ∼120 mT (or g ⊥ = 6) indicates high-spin heme where Fe(ІІІ) is hexa-co-ordinated with a proximal ligand from L-PGDS and a weak distal ligand, probably H 2 O [61,62]. The cw EPR spectrum of L-PGDS is plotting the increase in absorbance at 652 nm for the oxidized TMB substrate versus time.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Amyloid β chaperone — lipocalin-type prostaglandin D synthase acts as a peroxidase in the presence of heme

Phillips

Kannaian

Yang

et al. 2020

Biochemical Journal

View full text Add to dashboard Cite

The extracellular transporter, lipocalin-type prostaglandin D synthase (L-PGDS) binds to heme and heme metabolites with high affinity. It has been reported that L-PGDS protects neuronal cells against apoptosis induced by exposure to hydrogen peroxide. Our study demonstrates that when human WT L-PGDS is in complex with heme, it exhibits a strong peroxidase activity thus behaving as a pseudo-peroxidase. Electron paramagnetic resonance studies confirm that heme in the L-PGDS–heme complex is hexacoordinated with high-spin Fe(III). NMR titration of heme in L-PGDS points to hydrophobic interaction between heme and several residues within the β-barrel cavity of L-PGDS. In addition to the transporter function, L-PGDS is a key amyloid β chaperone in human cerebrospinal fluid. The presence of high levels of bilirubin and its derivatives, implicated in Alzheimer's disease, by binding to L-PGDS may reduce its chaperone activity. Nevertheless, our ThT binding assay establishes that heme and heme metabolites do not significantly alter the neuroprotective chaperone function of L-PGDS. Guided by NMR data we reconstructed the heme L-PGDS complex using extensive molecular dynamics simulations providing a platform for mechanistic interpretation of the catalytic and transporting functions and their modulation by secondary ligands like Aβ peptides and heme metabolites.

show abstract

Section: Resultssupporting

confidence: 76%

Section: Resultsmentioning

confidence: 99%

Amyloid β chaperone — lipocalin-type prostaglandin D synthase acts as a peroxidase in the presence of heme

Phillips

Kannaian

Yang

et al. 2020

Biochemical Journal

View full text Add to dashboard Cite

show abstract

“…Electron Paramagnetic Resonance (EPR) can provide valuable information about the oxidation state of an atom or atoms within a (macro)molecule and its environment by using unpaired electrons as probes. The technique has been used to study various paramagnetic species [1,2] such as organic radicals, [3][4][5] proteins, [6][7][8][9] polymers [5,10] and transition-metal complexes. [11,12] Although EPR spectrometers operating at up to 263 GHz are now commercially available, X-band (~9 GHz) equipment is still the most widely used.…”

Section: Introductionmentioning

confidence: 99%

A Versatile In‐Situ Electron Paramagnetic Resonance Spectro‐electrochemical Approach for Electrocatalyst Research

et al. 2020

Self Cite

View full text Add to dashboard Cite

Empirical electrocatalyst research generally consists of the synthesis and experimental characterization of catalysts and the analysis of electrolysis products by conventional analytical techniques. In‐situ electron paramagnetic resonance spectro‐electrochemistry provides an evidence‐based in‐depth understanding of the formed intermediates and the reaction mechanism enabling the desired tuning of electrocatalysts. The use of this technique has been underexploited because of the opposite requirements they impose on the conventional setup. In this work, a versatile electrode with commercially available indium tin oxide on polyethylene terephthalate (PET) was constructed for the first time which can fit inside commonly used flat cells. It allows reproducible electrodeposition of catalytic material combined with sensitive radical detection, owing to its large surface area and minimal disruption to the resonator's Q‐factor. Moreover, with a resistivity of 8–10 Ω sq−1, the surface potential of the thin semiconductor electrode within the resonator was well‐controlled, allowing targeted radical production.

show abstract

“…Nuclei in the immediate vicinity of the metal center can also be observed in EPR‐based approaches (ENDOR, ESEEM, HYSCORE) [84–89] . These approaches are also particularly powerful in (e.g.)…”

Section: Resultsmentioning

confidence: 99%

A High‐Resolution View of the Coordination Environment in a Paramagnetic Metalloprotein from its Magnetic Properties

et al. 2021

View full text Add to dashboard Cite

Metalloproteins constitute a significant fraction of the proteome of all organisms and their characterization is critical for both basic sciences and biomedical applications. A large portion of metalloproteins bind paramagnetic metal ions, and paramagnetic NMR spectroscopy has been widely used in their structural characterization. However, the signals of nuclei in the immediate vicinity of the metal center are often broadened beyond detection. In this work, we show that it is possible to determine the coordination environment of the paramagnetic metal in the protein at a resolution inaccessible to other techniques. Taking the structure of a diamagnetic analogue as a starting point, a geometry optimization is carried out by fitting the pseudocontact shifts obtained from first principles quantum chemical calculations to the experimental ones.

show abstract

Electron paramagnetic resonance of globin proteins – a successful match between spectroscopic development and protein research

Cited by 7 publications

References 152 publications

Amyloid β chaperone — lipocalin-type prostaglandin D synthase acts as a peroxidase in the presence of heme

Amyloid β chaperone — lipocalin-type prostaglandin D synthase acts as a peroxidase in the presence of heme

A Versatile In‐Situ Electron Paramagnetic Resonance Spectro‐electrochemical Approach for Electrocatalyst Research

A High‐Resolution View of the Coordination Environment in a Paramagnetic Metalloprotein from its Magnetic Properties

Contact Info

Product

Resources

About