Theoretical Studies of Protein-Ligand Interactions
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]
The protein-ligand interaction is an important issue in rational drug design and protein function research. This thesis focuses on the study of protein-ligand interactions using various molecular modeling methods, which are used in combination to predict the binding modes and calculate the binding free energies of several important protein-ligand systems, as summarized below.
In Paper I, we investigated the binding profile of a type I positive allosteric modulator (PAM) NS-1738 with the α7-nicotinic acetylcholine receptor (α7-nAChR). NS-1738 is found to have three different binding sites on α7-nAChR and has moderate binding affinities to the receptor.
In Paper II, we revealed the binding mechanism of a PET radio-ligand [18F]ASEM with α7-nAChR. Using metadynamics simulations, we managed to find a stable state which is not observed in molecular docking and unbiased molecular dynamics simulations. Free energy analysis further confirmed that this stable state is the global minimum with respect to the selected collective variables.
In Paper III, we studied the binding modes and binding affinities of two probes (AZD2184 and thioflavin T) for the detection of amyloid β(1-42) fibrils in clinical studies. We found that AZD2184 and thioflavin T are able to bind to several sites of the Aβ(1-42) fibril. Due to the small size, planarity and neutrality of AZD2184, it binds more strongly with Aβ(1-42) fibril at all sites. By contrast, thioflavin T has more significant conformational changes after binding, which is the reason that thioflavin T can be used as a fluorescent probe in in vitro studies.
In Paper IV, we studied the binding profile of PtdIns(3,4,5)P3 with the plecsktrin homology (PH) domain of Saprolegnia monoica cellulose synthase. We first studied the binding modes of the inositol groups with the PH domain in solution, the results of which were then used to guide the modeling of the binding mode of PtdIns(3,4,5)P3 in a membrane with the PH domain.
Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2016. , p. x, 52
Series
TRITA-BIO-Report, ISSN 1654-2312
Keywords [en]
Binding free energy, molecular dynamics, molecular docking, metadynamics, nicotinic receptor, amyloid fibril, PH domain
National Category
Theoretical Chemistry
Research subject
Theoretical Chemistry and Biology
Identifiers
URN: urn:nbn:se:kth:diva-186192ISBN: 978-91-7595-985-6 (print)OAI: oai:DiVA.org:kth-186192DiVA, id: diva2:926080
Public defence
2016-05-26, FB52, Roslagstullsbacken 15, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC 20150504
2016-05-042016-05-042016-06-20Bibliographically approved
List of papers