PMID- 28737791
OWN - NLM
STAT- MEDLINE
DCOM- 20180212
LR  - 20180212
IS  - 1463-9084 (Electronic)
IS  - 1463-9076 (Linking)
VI  - 19
IP  - 31
DP  - 2017 Aug 9
TI  - Aqueous ionic liquids and their influence on peptide conformations: denaturation 
      and dehydration mechanisms.
PG  - 20430-20440
LID - 10.1039/c7cp02897k [doi]
AB  - Low concentrated aqueous ionic liquids (ILs) and their influence on protein 
      structures have attracted a lot of interest over the last few years. This can be 
      mostly attributed to the fact that aqueous ILs, depending on the ion species 
      involved, can be used as protein protectants or protein denaturants. Atomistic 
      molecular dynamics (MD) simulations are performed in order to study the influence 
      of different aprotic ILs on the properties of a short hairpin peptide. Our 
      results reveal distinct binding and denaturation effects for 
      1-ethyl-3-methylimidazolium (EMIM) in combination with different anions, namely, 
      chloride (CL), tetrafluoroborate (BF4) and acetate (ACE). The simulation outcomes 
      demonstrate that the studied ILs with larger anions reveal a more pronounced 
      accumulation behavior of the individual ion species around the peptide, which is 
      accomplished by a stronger dehydration effect. We can relate these findings to 
      the implications of the Kirkwood-Buff theory, which provides a thermodynamic 
      explanation for the denaturation strength in terms of the IL accumulation 
      behavior. The results for the spatial distribution functions, the binding 
      energies and the local/bulk partition coefficients are in good agreement with 
      metadynamics simulations in order to determine the energetically most stable 
      peptide conformations. The free energy landscapes indicate a decrease of the 
      denaturation strength in the order EMIM/ACE, EMIM/BF4 and EMIM/CL, which 
      coincides with a decreasing size of the anion species. An analysis of the 
      potential binding energies reveals that this effect is mainly of enthalpic 
      nature.
FAU - Diddens, Diddo
AU  - Diddens D
AD  - Institute of Physical Chemistry, University of Munster, Corrensstrasse 28/30, 
      48149 Munster, Germany.
FAU - Lesch, Volker
AU  - Lesch V
FAU - Heuer, Andreas
AU  - Heuer A
FAU - Smiatek, Jens
AU  - Smiatek J
LA  - eng
PT  - Journal Article
PL  - England
TA  - Phys Chem Chem Phys
JT  - Physical chemistry chemical physics : PCCP
JID - 100888160
RN  - 0 (Anions)
RN  - 0 (Borates)
RN  - 0 (Chlorides)
RN  - 0 (Imidazoles)
RN  - 0 (Ionic Liquids)
RN  - 0 (Peptides)
RN  - 059QF0KO0R (Water)
RN  - H429WZ9FBQ (fluoroboric acid)
RN  - TVE1D62MAK (1-ethyl-3-methylimidazolium)
SB  - IM
MH  - Anions/chemistry
MH  - Borates/chemistry
MH  - Chlorides/chemistry
MH  - Imidazoles/chemistry
MH  - Ionic Liquids/*chemistry
MH  - Molecular Dynamics Simulation
MH  - Peptides/*chemistry/metabolism
MH  - Protein Denaturation
MH  - Protein Structure, Tertiary
MH  - Thermodynamics
MH  - Water/chemistry
EDAT- 2017/07/25 06:00
MHDA- 2018/02/13 06:00
CRDT- 2017/07/25 06:00
PHST- 2017/07/25 06:00 [pubmed]
PHST- 2018/02/13 06:00 [medline]
PHST- 2017/07/25 06:00 [entrez]
AID - 10.1039/c7cp02897k [doi]
PST - ppublish
SO  - Phys Chem Chem Phys. 2017 Aug 9;19(31):20430-20440. doi: 10.1039/c7cp02897k.