Université de Strasbourg

Petra Hellwig


Complex Matter Chemistry (CMC), University of Strasbourg and CNRS

Petra Hellwig, USIAS Fellow 2018

Professor Petra Hellwig received her PhD in 1998 from the University of Erlangen (Germany) under the supervision of Werner Mäntele. From 1998 to 1999 and from 2001 to 2005 she was a researcher at the Institute of Biophysics at the University of Frankfurt and, from 1999 to 2001, at the University of Illinois Urbana-Champaign (USA). After her habilitation in 2002, she was appointed professor in 2005 at the University of Strasbourg.

She is a professor in the Faculty of Chemistry and directs the research unit Chemistry of Complex Matter as well as the Laboratory of Bioelectrochemistry and Spectroscopy. She was awarded an ANR (French National Research Agency) Junior Chair of Excellence  in 2007 and was junior member of the Institut Universitaire de France (IUF) from 2010-2015.

With her interdisciplinary expertise in biophysics and physical chemistry she uses vibrational spectroscopy and bioelectrochemistry for the study of the reaction mechanism of membrane proteins and their principle(s) of operation. Her research focuses on enzymes from the respiratory chain and as membrane transporters.

Project - The reaction mechanism of proteins studied in nanopores

November 2018 – April 2021

Membrane proteins are essential to crucial processes such as membrane transport, signaling, respiration and photosynthesis. It is estimated that, in the next century, 80 to 90% of ‘druggable’ targets are membrane proteins. Their contributions to the energy state of the cell are ruled by their conformation and position, as well as the reactivity of specific residues, in response to the electrochemical ion gradients that are composed of an electrical and a concentration component. A common motif in proton translocating membrane proteins consists of several well-defined acid/base pair(s) with specifically shifted pK values, a topic that is increasingly at the focus of current frontier research.

Here we develop an approach allowing the in situ identification of protonation/de-protonation of specific residues in response to the conformation of the membrane protein and to the membrane potential by infrared spectroscopy, more specifically the lactose permease. Vibrational spectroscopies provide molecular fingerprints of the catalytic reaction of a protein. By combining infrared spectroscopies and solid-state plasmonic nanostructures with an excitation at wavelengths that are specific for the signature of protonated acidic residues, protein backbone and the overall hydrogen-bonding network in the protein, we aim to monitor the reactions of the protein during catalysis. The individual nanoreactors will be coupled to electrochemistry in order to mimic the natural potential of the membrane, thus allowing us to perform a label free detection of the catalytic reaction and the conformational control within crucial membrane proteins. 

Post-doc biography - Fatima Omeis

Complex Matter Chemistry (CMC), University of Strasbourg and CNRS

Fatima Omeis

Fatima Omeis studied fundamental physics at the Lebanese University, Lebanon. In 2014, she continued her research studies in electromagnetism and plasmonics in the infrared range under the supervision of Professor Emmanuel Centeno and obtained her PhD in Physics in September 2017 from the University of Clermont Auvergne, France. Following her PhD, she joined the group of Professor Francesco De Angelis at the Istituto Italiano di Tecnologia (IIT), Italy as a post-doctoral researcher. She worked on the theory of plasmonic devices to detect single DNA bases using Raman spectroscopy.

Since 2018, Fatima has been a post-doctoral researcher in Professor Petra Hellwig’s group in the laboratory of Bioelectrochemistry and Spectroscopy UMR 7140 in Strasbourg. Her research programme focuses on following the reaction mechanism of proteins in plasmonic nanodevices. Her interests are in using the plasmonics and metamaterial field to better understand biological molecules and their behaviour on the nanometric scale, which can be a doorway to treat various incurable diseases such as Huntington’s and Alzheimer’s.


Publications linked to project:

France 2030