TY  - JOUR
A1  - Kuekenshoener, Tim
A1  - Wohlwend, Daniel
A1  - Niemoeller, Christoph
A1  - Dondapati, Padmarupa
A1  - Speck, Janina
A1  - Adeniran, Adebola V.
A1  - Nieth, Anita
A1  - Gerhardt, Stefan
A1  - Einsle, Oliver
A1  - Mueller, Kristian M.
A1  - Arndt, Katja Maren
T1  - Improving coiled coil stability while maintaining specificity by a bacterial hitchhiker selection system
JF  - Journal of structural biology
N2  - The design and selection of peptides targeting cellular proteins is challenging and often yields candidates with undesired properties. Therefore we deployed a new selection system based on the twin-arginine translocase (TAT) pathway of Escherichia coli, named hitchhiker translocation (HiT) selection. A pool of alpha-helix encoding sequences was designed and selected for interference with the coiled coil domain (CC) of a melanoma-associated basic-helix-loop-helix-leucine-zipper (bHLHLZ) protein, the microphthalmia associated transcription factor (MITF). One predominant sequence (iM10) was enriched during selection and showed remarkable protease resistance, high solubility and thermal stability while maintaining its specificity. Furthermore, it exhibited nanomolar range affinity towards the target peptide. A mutation screen indicated that target-binding helices of increased homodimer stability and improved expression rates were preferred in the selection process. The crystal structure of the iM10/MITF-CC heterodimer (2.1 angstrom) provided important structural insights and validated our design predictions. Importantly, iM10 did not only bind to the MITF coiled coil, but also to the markedly more stable HLHLZ domain of MITF. Characterizing the selected variants of the semi-rational library demonstrated the potential of the innovative bacterial selection approach. (C) 2014 Elsevier Inc. All rights reserved.
KW  - Basic helix-loop-helix leucine zipper
KW  - Coiled coils
KW  - Microphthalmia associated transcription factor
KW  - Selection and design
KW  - Twin arginine translocation pathway
Y1  - 2014
U6  - https://doi.org/10.1016/j.jsb.2014.03.002
SN  - 1047-8477
SN  - 1095-8657
VL  - 186
IS  - 3
SP  - 335
EP  - 348
PB  - Elsevier
CY  - San Diego
ER  - 
TY  - JOUR
A1  - Kuekenshoener, Tim
A1  - Hagemann, Urs B.
A1  - Wohlwend, Daniel
A1  - Raeuber, Christina
A1  - Baumann, Tobias
A1  - Keller, Sandro
A1  - Einsle, Oliver
A1  - Mueller, Kristian M.
A1  - Arndt, Katja Maren
T1  - Analysis of Selected and Designed Chimeric D- and L-alpha-Helix Assemblies
JF  - Biomacromolecules : an interdisciplinary journal focused at the interface of polymer science and the biological sciences
N2  - D-Peptides have been attributed pharmacological advantages over regular L-peptides, yet design rules are largely unknown. Based on a designed coiled coil-like D/L heterotetramer, named L-Base/D-Acid, we generated a library offering alternative residues for interaction with the D-peptide. Phage display selection yielded one predominant peptide, named HelixA, that differed at 13 positions from the scaffold helix. In addition to the observed D-/L-heterotetramers, ratio-dependent intermediate states were detected by isothermal titration calorimetry. Importantly, the formation of the selected HelixA/D-Acid bundle passes through fewer intermediate states than L-Base/D-Acid. Back mutation of HelixA core residues to L-Base (HelixLL) revealed that the residues at e/g-positions are responsible for the different intermediates. Furthermore, a Val-core variant (PeptideVV) was completely devoid of binding D-Acid, whereas an Ile-core helix (HelixII) interacted with D-Acid in a significantly more specific complex than L-Base.
Y1  - 2014
U6  - https://doi.org/10.1021/bm5006883
SN  - 1525-7797
SN  - 1526-4602
VL  - 15
IS  - 9
SP  - 3296
EP  - 3305
PB  - American Chemical Society
CY  - Washington
ER  -