Publications associées à Hème

Ultrafast X-ray Spectroscopy of Haem Proteins

Majed Chergui, Camila Bacellar Cases Da Silveira

In this article we revisit our recent picosecond and femtosecond X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) experiments, probing the ultrafast electronic and geometric evolution of photoexcited haem proteins, namely ferrous N ...

SWISS CHEMICAL SOC2022

Spin cascade and doming in ferric hemes: Femtosecond X-ray absorption and X-ray emission studies

Majed Chergui, Christopher Alexander Arrell, Wojciech Gawelda, Giulia Fulvia Mancini, Camila Bacellar Cases Da Silveira, Frederico Alves Lima, Dominik Kinschel, Oliviero Cannelli, Jérémy Raymond Jean Maurice Rouxel, Rebecca Ann Ingle

The structure-function relationship is at the heart of biology, and major protein deformations are correlated to specific functions. For ferrous heme proteins, doming is associated with the respiratory function in hemoglobin and myoglobins. Cytochrome c (C ...

National Academy of Sciences2020

Effect of Single-Point Mutations on Nitric Oxide Rebinding and the Thermodynamic Stability of Myoglobin

Polydefkis Diamantis

The effect of single amino acid mutations on the rebinding dynamics of nitrogen monoxide (NO) to myoglobin is investigated using reactive molecular dynamics simulations. In particular, mutations of residues surrounding the heme-active site (Leu29, His64, V ...

AMER CHEMICAL SOC2019

More Medicines for Tuberculosis: Fuelling Drug Discovery against Mycobacterium tuberculosis

Shi-Yan Caroline Foo

Tuberculosis (TB), whose etiological agent is Mycobacterium tuberculosis (M. tuberculosis), has plagued humanity since antiquity. Even with chemotherapy available today, TB is the leading cause of death due to an infectious disease. Modern day factors, suc ...

EPFL2018

Non-invasive continuous monitoring of pro-oxidant effects of engineered nanoparticles on aquatic microorganisms

Olivier Martin, Paul Bowen, Christian Santschi, Volodymyr Koman, Nadia Rachel Von Moos

Engineered nanomaterials (ENMs) are key drivers for the development of highly sophisticated new technologies. As all new attainments, the rapidly increasing used of ENMs raise concerns about their safety for the environment and humans. There is growing evi ...

2017

Photo-induced oxidation of the uniquely liganded heme f in the cytochrome b(6)f complex of oxygenic photosynthesis

Frank van Mourik, Andre Al Haddad, Adrien Alexis Paul Chauvet, Rachna Agarwal

The ultrafast behavior of the ferrous heme f from the cytochrome b(6)f complex of oxygenic photosynthesis is revealed by means of transient absorption spectroscopy. Benefiting from the use of microfluidic technologies for handling the sample as well as fro ...

Royal Society of Chemistry2016

Tryptophan-to-heme electron transfer in ferrous myoglobins

Majed Chergui, Frank van Mourik, Andre Al Haddad, Gerald Auböck, Roberto Monni

It was recently demonstrated that in ferric myoglobins (Mb) the fluorescence quenching of the photoexcited tryptophan 14 (*Trp(14)) residue is in part due to an electron transfer to the heme porphyrin (porph), turning it to the ferrous state. However, the ...

National Academy of Sciences2015

Photo-induced dynamics of the heme centers in cytochrome bc(1)

Majed Chergui, Frank van Mourik, Andre Al Haddad, Adrien Alexis Paul Chauvet

The ultrafast response of cytochrome bc1 is investigated for the first time, via transient absorption spectroscopy. The distinct redox potentials of both c(1)- and b-hemes allow for a clear differentiation of their respective signals. We find that while th ...

Royal Society of Chemistry2015

Portable oxidative stress sensor: Dynamic and non-invasive measurements of extracellular H2O2 released by algae

Christian Santschi, Olivier Martin, Volodymyr Koman

Reactive oxygen species (ROS) generated by aerobic organisms are essential for physiological processes such as cell signaling, apoptosis, immune defense and oxidative stress mechanisms. Unbalanced oxidant/antioxidant budgets are involved in many diseases a ...

Elsevier2015

A cascade through spin states in the ultrafast haem relaxation of met-myoglobin

Majed Chergui, Frank van Mourik, Cristina Consani, Gerald Auböck, Olivier Christian Bräm

We report on a study of the early relaxation processes of met-Myoglobin in aqueous solution, using a combination of ultrafast broadband fluorescence detection and transient absorption with a broad UV-visible continuum probe at different pump energies. Reco ...

American Institute of Physics2014