TY  - JOUR
A1  - Mandl, Thomas
A1  - Sinelnikova, Anna
A1  - Östlin, Christofer
A1  - Grånäs, Oscar
A1  - Brodmerkel, Maxim N.
A1  - Markl, Erik G.
A1  - Caleman, Carl
T1  - Reproducibility in the unfolding process of protein induced by an external electric field
JF  - Chemical Science
N2  - The dynamics of proteins are crucial for their function. However, commonly used techniques for studying protein structures are limited in monitoring time-resolved dynamics at high resolution. Combining electric fields with existing techniques to study gas-phase proteins, such as single particle imaging using free-electron lasers and gas-phase small angle X-ray scattering, has the potential to open up a new era in time-resolved studies of gas-phase protein dynamics. Using molecular dynamics simulations, we identify well-defined unfolding pathways of a protein, induced by experimentally achievable external electric fields. Our simulations show that strong electric fields in conjunction with short-pulsed X-ray sources such as free-electron lasers can be a new path for imaging dynamics of gas-phase proteins at high spatial and temporal resolution.
KW  - Reproducibility protein
Y1  - 
ER  - 
TY  - JOUR
A1  - Sinelnikova, Anna
A1  - Mandl, Thomas
A1  - Agelii, Harald
A1  - Grånäs, Oscar
A1  - Marklund, Erik G.
A1  - Caleman, Carl
A1  - De Santis, Emiliano
T1  - Protein orientation in time-dependent electric fields: orientation before destruction
JF  - Biophysical Journal
KW  - Protein
KW  - Electric Fields
Y1  - 
IS  - Volume 120, Issue 17
SP  - 3709
EP  - 3717
ER  - 
TY  - JOUR
A1  - Kierspel, Thomas
A1  - Kadek, Alan
A1  - Barran, Perdita
A1  - Bellina, Bruno
A1  - Bijedic, Adi
A1  - Brodmerkel, Maxim N.
A1  - Commandeur, Jan
A1  - Caleman, Carl
A1  - Damjanovic, Tomislav
A1  - Dawod, Ibrahim
A1  - De Santis, Emiliano
A1  - Lekkas, Alexandros
A1  - Lorenzen, Kristina
A1  - López Morillo, Luis
A1  - Mandl, Thomas
A1  - Marklund, Erik G.
A1  - Papanastasiou, Dimitris
A1  - Ramakers, Lennart A. I.
A1  - Schweikhard, Lutz
A1  - Simke, Florian
A1  - Sinelnikova, Anna
A1  - Smyrnakis, Athanasios
A1  - Timneanu, Nicusor
A1  - Uetrecht, Charlotte
T1  - Coherent diffractive imaging of proteins and viral capsids: simulating MS SPIDOC
JF  - Analytical and Bioanalytical Chemistry
N2  - MS SPIDOC is a novel sample delivery system designed for single (isolated) particle imaging at X-ray Free-Electron Lasers
that is adaptable towards most large-scale facility beamlines. Biological samples can range from small proteins to MDa
particles. Following nano-electrospray ionization, ionic samples can be m/z-filtered and structurally separated before being
oriented at the interaction zone. Here, we present the simulation package developed alongside this prototype. The first part
describes how the front-to-end ion trajectory simulations have been conducted. Highlighted is a quadrant lens; a simple but
efficient device that steers the ion beam within the vicinity of the strong DC orientation field in the interaction zone to ensure
spatial overlap with the X-rays. The second part focuses on protein orientation and discusses its potential with respect to
diffractive imaging methods. Last, coherent diffractive imaging of prototypical T = 1 and T = 3 norovirus capsids is shown.
We use realistic experimental parameters from the SPB/SFX instrument at the European XFEL to demonstrate that low-
resolution diffractive imaging data (q < 0.3 nm −1 ) can be collected with only a few X-ray pulses. Such low-resolution data
are sufficient to distinguish between both symmetries of the capsids, allowing to probe low abundant species in a beam if
MS SPIDOC is used as sample delivery.
KW  - SPI
KW  - X-ray
KW  - Native MS
KW  - Protein complex structure
KW  - Simulation
Y1  - 
U6  - http://dx.doi.org/https://doi.org/10.1007/s00216-023-04658-y
VL  - 2023
IS  - 415
SP  - 4209
EP  - 4220
ER  -