Ebru Demet Akdoğan

Akdoğan, Ebru Demet

Name Variants

Akdoğan, E.
Akdoğan, EBRU DEMET
E. D. Akdoğan
A., Ebru Demet
Ebru Demet Akdoğan
Akten E.
Akdoğan,E.D.
AKDOĞAN, EBRU DEMET
Akdogan,Ebru Demet
Akdogan,E.D.
Akdogan, Ebru Demet
Ebru Demet AKDOĞAN
E. Akdoğan
EBRU DEMET AKDOĞAN
Ebru Demet, Akdogan
Akdoğan, Ebru Demet
Akdoğan, E. D.
A.,Ebru Demet
AKDOĞAN, Ebru Demet

Job Title

Prof. Dr.

Email Address

demet.akten@khas.edu.tr

ORCID ID

0000-0002-0358-3171

Scopus Author ID

6507297154

Full item page

Scholarly Output

10

Articles

3

Citation Count

41

Supervised Theses

3 Scholarly Output Search Results

Now showing 1 - 6 of 6

The prediction of 3d structure of the dimeric state of human β2-adrenergic receptor
(Kadir Has Üniversitesi, 2016) Akdoğan, Ebru Demet; Akdoğan, Ebru Demet
A significant amount of experimental and computational data points out a possible role of TM6 in the dimerization of ?2-adrenergic receptor (?2AR). Peptide– and protein–protein docking experiments guided by this assumption were conducted in order to confirm the potential participation of TM6 at the interface region of ?2AR dimers. Firstly a derived peptide consisting of 23 residues of TM6 was blindly docked to ?2AR monomer using a rigid body approach. The resulting complexes in which the peptide preferred to be near TM5 and TM6 regions have also the highest scores. Secondly a total of seven peptides were derived from each TM regions and were blindly docked to ?2AR using the same rigid body approach. TM6 was found to be the most preferred binding site region in the receptor for each peptide. As for the protein-protein dockings a full rigid-body docking returned a total of 16000 dimer conformations and is followed by a membrane topology filtering. 149 complexes fit the topology requirements. A root mean-squared deviance (RMSD) value of 6 Å was used to cluster all 149 complexes and it is observed that the highest populated cluster of conformers have the highest score value and moreover TM6 presents at the interface region. Finally an information-driven semi flexible docking approach used by given the interface residue data for seven TM regions. interface residue data derived from the SASA values of residues in each TM region. The generated complexes were filtered due to membrane topology requirements. The complex with the TM6 interface was the highest scored docking pose among the complexes with a proper membrane topology.
Investigation of allosteric inhibition effect in pyruvate kinase by constrained molecular dynamics simulation method Piruvat kinazın allosterik olarak inhibe edilmesinin kısıtlanmış moleküler dinamik similasyon methodu kullanılarak incelenmesi
(Kadir Has Üniversitesi, 2021) Akdoğan, Ebru Demet; Akdoğan, Ebru Demet
In previous studies, our research group identified species-specific allosteric sites in glycolytic enzymes from different organisms and identified candidate inhibitory molecules that strongly interact with the residues at these sites. In this study, a Molecular Dynamics simulation study was performed on one of the glycolytic enzymes, bacterial pyruvate kinase (S. aureus PK), by employing bond restraints between selected pairs of residues at the suggested allosteric region in order to mimic the presence of a drug molecule. At the same time, interacting residues in an ex- perimentally identified allosteric region were also restricted and compared with the proposed area. Three 100 ns long independent runs were conducted for each of three different states of the receptor; apo state (no restraints), constr-1 (restriction on proposed allosteric site) and constr-2 (restriction on known allosteric site) which amount to a total of nine runs, e.g., 900 ns. Several analytical methods were used to elucidate the effect of restricted regions on protein dynamics and the allosteric character of pyruvate kinase. While structural changes were examined with RMSD-RMSF analysis, correlations between global movements and structural components were analysed with principal component analysis. From PCA results, it was observed that both restricted allosteric regions led to decreased correlations of positional fluctuations in comparison to apo state. Investigation of changes in the secondary structure at the catalytic site showed that the α′6 helix, which has an essential role in the stabilization of the active structure, shifted to a coil-turn structure in the apo state more frequently than in the con- strained states. Additionally, domain rotations identified via principal axes analysis, showed that the constrained state disrupted the domain rotations more often. Finally, the distance fluctuation analysis was performed to observe the effect of the restricted residues in the allosteric signal transduction. The communications be- tween residues increased in the constr-1 state while there was slight decrease in the communications of the constr-2 state.
Citation Count: 16
In silico design of novel and highly selective lysine-specific histone demethylase inhibitors
(Scientific Technical Research Council Turkey-Tubitak, 2011) Akdoğan, Ebru Demet; Yelekçi, Kemal; Yelekçi, Kemal
Histone lysine-specific demethylase (LSD1) is involved in a wide range of epigenetic processes and plays important roles in gene silencing DNA transcription DNA replication DNA repair and heterochromatin formation. Its active site shows a resemblance to those of 2 homologous enzymes monamine oxidase A and B (MAO-A and MAO-B.) In the present work starting from suitable scaffolds and generating thousands of structures from them 10 potential inhibitors were obtained with structural and physicochemical properties selectively suitable for inhibiting LSD1. iLib Diverse software was used to generate the diverse structures and 3 docking tools CDOCKER GOLD and AutoDock were used to find the most probable potential inhibitor based on its binding affinity. The dispositions of the candidate molecules within the organism were checked by ADMET_PSA_2D (polar surface area) versus ADMET_AlogP98 (the logarithm of the partition coefficient between n-octanol and water) and their suitability is discussed. The LSD1 inhibition activities of the candidates were compared with the properties of trans-2-phenylcyclopropylamine (tranylcypromine) and 2-(4-methoxy-phenyl) cyclopropylamine which are the 2 known inhibitors of LSD1.
Citation Count: 24
How an Inhibitor Bound to Subunit Interface Alters Triosephosphate Isomerase Dynamics
(Cell Press, 2015) Akdoğan, Ebru Demet; Fındık, Doğa; Akdoğan, Ebru Demet; Doruker, Pemra
The tunnel region at triosephosphate isomerase (TIM)'s dimer interface distant from its catalytic site is a target site for certain benzothiazole derivatives that inhibit TIM's catalytic activity in Trypanosoma cruzi the parasite that causes Chagas disease. We performed multiple 100-ns molecular-dynamics (MD) simulations and elastic network modeling (ENM) on both apo and complex structures to shed light on the still unclear inhibitory mechanism of one such inhibitor named bt10. Within the time frame of our MD simulations we observed stabilization of aromatic clusters at the dimer interface and enhancement of intersubunit hydrogen bonds in the presence of bt10 which point to an allosteric effect rather than destabilization of the dimeric structure. The collective dynamics dictated by the topology of TIM is known to facilitate the closure of its catalytic loop over the active site that is critical for substrate entrance and product release. We incorporated the ligand's effect on vibrational dynamics by applying mixed coarse-grained ENM to each one of 54000 MD snapshots. Using this computationally efficient technique we observed altered collective modes and positive shifts in eigenvalues due to the constraining effect of bt10 binding. Accordingly we observed allosteric changes in the catalytic loop's dynamics flexibility and correlations as well as the solvent exposure of catalytic residues. A newly (to our knowledge) introduced technique that performs residue-based ENM scanning of TIM revealed the tunnel region as a key binding site that can alter global dynamics of the enzyme.
Pharmacophore- based screening and docking for the discovery of novel antagonists of Beta-2 adrenergic receptor
(Kadir Has Üniversitesi, 2013) Akdoğan, Ebru Demet; Akdoğan, Ebru Demet
ß2AR which is the member of rhodopsin-like GPCR is the target system for the discovery of novel antagonists using structure-based pharmacophore modeling and docking methods. initially a shared pharmacophore model is obtained using the structure of five known inactive ß2AR complex (PDB ids: 2HR1 3D4S 3NY8 3NY9 and 3NYA). in order to test the discriminatory power of pharmacophore model a small database consisting of 117 known molecules (53 antagonists against 64 agonists) was screened using LigandScout software tool. The screening yielded 44 antagonists (72% true positives) against 17 agonists (18% false positives) which was found satisfactory. Then under the same screening conditions the second database that is the clean drug-like subset of ZiNC database was screened. -- Abstract'tan.
Citation Count: 1
Exploring distinct binding site regions of beta(2)-adrenergic receptor via coarse-grained molecular dynamics simulations
(Scientific Technical Research Council Turkey-Tubitak, 2013) Akdoğan, Ebru Demet; Akdoğan, Ebru Demet
beta(2)-Adrenergic receptor (beta(2)AR) is a G protein-coupled receptor that is highly flexible and able to recognize a wide range of ligands through its conformational variations. Active and inactive conformations revealed by recent crystallographic experiments do not provide a complete dynamic picture of the receptor especially in the binding site. In this study molecular dynamics (MD) simulation through a residue-based coarse-grained model is used as an alternative and efficient method to explore a wider conformational search space. The system was composed of beta(2)AR embedded into a 1-palmitoyl-2-oleoyl-phosphatidylcholine membrane bilayer with surrounding water. A total of 6 mu s of simulation at constant NPT was performed for a system of 6868 coarse-grained beads. The system reached equilibrium at around 0.1 mu s. The overall 3-dimensional structure was well preserved throughout the simulation. Local residue-based fluctuations were in good agreement with fully atomistic MD simulations. Four distinct snapshots were selected and reverse-mapped to all-atom representations with around 65000 atoms. Each reverse-mapped system was later subjected to 100 ns of MD simulation for equilibration. Root mean square deviation clustering analysis yielded distinct receptor conformers for the binding site regions which were suggested to be alternative representations of the binding pocket and thus were proposed as plausible targets in docking-based virtual screening experiments for the discovery of novel antagonists.