Protein-Cofactor Interactions

25. Proton-Pumping Microbial Rhodopsin from pathogenic fungi

Microbial rhodopsins have recently been discovered in pathogenic fungi and have been postulated to be involved in signaling during the course of an infection. Here, we characterize the photocycle of Ustilago maydis Rhodopsin 1.

La Greca & Chen et al., Front. Mol. Biosci., 2022, 9, 826990
The Photoreaction of the Proton-Pumping Rhodopsin 1 From the Maize Pathogenic Basidiomycete Ustilago maydis
DOI: 10.3389/fmolb.2022.826990

23. Electric Field Changes during Photoisomerization in Phytochromes

Photoisomerization in phytochromes leads to a functionally relevant transition of an α-helical segment to a β-sheet. Using nitrile probes on non-natural amino acids reveals electric field changes during this secondary structural change.

Kraskov et al., Biochemistry, 2021, 60, 2967-2977
Local Electric Field Changes during the Photoconversion of the Bathy Phytochrome Agp2.
DOI: 10.1021/acs.biochem.1c00426

21. The CO Ligand in CO-inhibited Cytochrome c Oxidase is Destabilized Electrostatically Prior to Dissosiation

The CO molecule is a known inhibitor of the reduced heme a3 active site in cytochrom c oxidase. However, even prior to oxidative dissociation, the CO is electrostatically destabilized in its position as ligand.

Baserga et al., Front. Sci., 2021, 9, 669452
Quantification of Local Electric Field Changes at the Active Site of Cytochrome c Oxidase by Fourier Transform Infrared Spectroelectrochemical Titrations.
DOI: 10.3389/fchem.2021.669452

10. Is the Hexameric tyrosine-coordinated heme protein from Silicibacter pomeroyi A heme Transporter?

Hexameric tyrosine-coordinated heme protein (HTHP) from Silicibacter pomeroyi has been shown to exhibit peroxidase- and catalase-like activity. In view of the striking similarity of HTHP to the heme carriers HasA or HmbR regarding redox potential, Fe-Tyr ligation, and heme release, we propose heme transport as an alternative or additional function.

Kielb et al., J. Phys. Chem. B, 2017
Switchable Redox Chemistry of the Hexameric Tyrosine-Coordinated Heme Protein.
DOI: 10.1021/acs.jpcb.7b01286

4. A New Artificial catalytic Oxo-Intermediate of Cytochrome C Oxidase

We investigate a novel oxo state of cytochrome c oxidase from Paracoccus denitrificans, which is generated by addition of ammonia and, as proposed, replaces the H2O/OH Ligand at the Cu in the binuclear center.

Kozuch et al., Biochemistry, 2013
Resonance Raman Characterization of the ammonia-generated intermediate of cytochrome c oxidase from Paracoccus denitrificans.
DOI: 10.1021/bi400535m