TY  - JOUR
A1  - Velk, Natalia
A1  - Uhlig, Katja
A1  - Vikulina, Anna
A1  - Duschl, Claus
A1  - Volodkin, Dmitry
T1  - Mobility of lysozyme in poly(L-lysine)/hyaluronic acid multilayer films
JF  - Colloids and surfaces : an international journal devoted to fundamental and applied research on colloid and interfacial phenomena in relation to systems of biological origin ; B, Biointerfaces
N2  - The spatial and temporal control over presentation of protein-based biomolecules such as growth factors and hormones is crucial for in vitro applications to mimic the complex in vivo environment. We investigated the interaction of a model protein lysozyme (Lys) with poly(L-lysine)/hyaluronic acid (PLL/HA) multilayer films. We focused on Lys diffusion as well as adsorption and retention within the film as a function of the film deposition conditions and post-treatment. Additionally, an effect of Lys concentration on its mobility was probed. A combination of confocal fluorescence microscopy, fluorescence recovery after photobleaching, and microfluidics was employed for this investigation. Our main finding is that adsorption of PLL and HA after protein loading induces acceleration and reduction of Lys mobility, respectively. These results suggest that a charge balance in the film to a high extent governs the protein-film interaction. We believe that control over protein mobility is a key to reach the full potential of the PLL/HA films as reservoirs for biomolecules depending on the application demand. (C) 2016 The Authors. Published by Elsevier B.V.
KW  - Layer-by-layer
KW  - Protein
KW  - Diffusion
KW  - Release
KW  - FRAP
Y1  - 2016
U6  - https://doi.org/10.1016/j.colsurfb.2016.07.055
SN  - 0927-7765
SN  - 1873-4367
VL  - 147
SP  - 343
EP  - 350
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Trautwein, Matthias
A1  - Fredriksson, Kai
A1  - Möller, Heiko Michael
A1  - Exner, Thomas E.
T1  - Automated assignment of NMR chemical shifts based on a known structure and 4D spectra
JF  - Journal of biomolecular NMR
N2  - Apart from their central role during 3D structure determination of proteins the backbone chemical shift assignment is the basis for a number of applications, like chemical shift perturbation mapping and studies on the dynamics of proteins. This assignment is not a trivial task even if a 3D protein structure is known and needs almost as much effort as the assignment for structure prediction if performed manually. We present here a new algorithm based solely on 4D [H-1, N-15]-HSQC-NOESY-[H-1, N-15]-HSQC spectra which is able to assign a large percentage of chemical shifts (73-82 %) unambiguously, demonstrated with proteins up to a size of 250 residues. For the remaining residues, a small number of possible assignments is filtered out. This is done by comparing distances in the 3D structure to restraints obtained from the peak volumes in the 4D spectrum. Using dead-end elimination, assignments are removed in which at least one of the restraints is violated. Including additional information from chemical shift predictions, a complete unambiguous assignment was obtained for Ubiquitin and 95 % of the residues were correctly assigned in the 251 residue-long N-terminal domain of enzyme I. The program including source code is available at https://github.com/thomasexner/4Dassign.
KW  - Chemical shift assignment
KW  - Protein
KW  - 3D structure
KW  - 4D NOESY
Y1  - 2016
U6  - https://doi.org/10.1007/s10858-016-0050-0
SN  - 0925-2738
SN  - 1573-5001
VL  - 65
SP  - 217
EP  - 236
PB  - Springer
CY  - Dordrecht
ER  -