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Gene & Protein in Disease                                               Effect of phytochemicals in diabetes



            of proteins . The target protein nature was determined by   of a ligand at the target region, chances of passage of the
                    [37]
            the SOSUI (engine ver. 1.11) server . The SWISS-MODEL   blood-brain barrier, toxicity, malignancy, etc.
                                       [38]
            server website was used for downloading a protein crystal
            three-dimensional  (3D)  structure .  SWISS-MODEL   2.6. Leads groundwork for docking
                                         [35]
            is a comparison modeling assistant processor and was   Avogadro 1.2.on-win 32 was applied for force field and
            applied to overlap proteins to assume its structural   geometry maximization of ligand . Hydrogen and charge
                                                                                         [48]
            sequence or arrangement, sequence identity, coverage,   were then added with the help of The UCSF Chimera
            model quality estimation (QMEAN SCORES), process,   tool . Torsion or tortuosities and level of freedom,
                                                                  [42]
            and resolution facts of the target protein. Ramachandran   followed  by stereo-chemical  distinction of  ligands, were
            Z-score and Ramachandran plot ZLab server were used to   accustomed, Gasteiger charges were considered, and the
            determine protein structure along with phi-psi background   PDB file was saved.
                     [39]
            probabilities . CASTp 3.0 software was used to identify
                                               [40]
            active sites and functional domains of targets .   2.7. Examination of target-lead interaction/docking
                                                               studies
            2.3. Target protein preparation                    The finally prepared PDB file of the target protein and
            Swiss-Pdb Viewer (aka Deep View) version 4.1.1 was applied   lead was opened in the UCSF Chimera tool. The Vina tool
            to reduce the target protein’s energy . UCSF Chimera tool   was used to calculate the potential energy of the docked
                                        [41]
            is an extensible molecular modeling system and was used   compound and the file was saved in PDBQT format.
            for the addition of hydrogen and charges, to adjust atomic-  BIOVIA Discovery Studio Visualizer 4.5 was used to
                                                                                          [49]
            subatomic torsion, degree of free will/freedom and stereo-  visualize target-ligand interactions . With the help of the
            chemical difference, and Gasteiger charges . Auto Dock   Discovery studio bonds detail, two-dimensional (2D) and
                                              [42]
            Vina and Chimera were used for grid preparation with   3D complex structures were analyzed.
            20 Å × 20 Å × 20 Å grid dimensions , and the X, Y, and Z
                                        [43]
            coordinates of the grid box were −76.407, −36.793, 13.714   3. Results
            for AMPK1, respectively, and −36.303, −82.337, −22.555   3.1. Target protein examination
            for AMPK2, respectively .
                               [40]
                                                               To prepare a strong and stable model of the target protein,
            2.4. The ligand library preparation                the selected targets and their properties were examined
                                                               critically. 5’-AMPK protein was selected as a target, and
            An extensive literature survey related to  C.  roseus   its catalytic subunits AMPK1 and AMPK2 sequence and
            revealed its major antihyperglycemic properties related to   active site were taken from and analyzed by UniProt site
            alkaloids [29,30,44] . The PubChem database was used to search   (Table 1). AMPK1 is a globular protein with an enzyme
            for alkaloid structure and control drug metformin. Eighty-  commission number (EC) of 2.7.11.1 , whereas AMPK2 is
                                                                                            [38]
            five compounds were selected from the database to prepare   a transmembrane protein with an EC number of 2.7.11.1 .
                                                                                                           [50]
            a library and metformin (CID: 4091) as a control drug.
            Followed by SDF, files were converted and saved in PDB   The online tool ProtPram was used for AMPK1 and AMPK2
            files by online software, Open Babel .             sequence analysis and their physicochemical properties
                                        [45]
                                                               identification (Table 1). ProtPram grand average of
            2.5. Absorption, distribution, metabolism,         hydropathicity (GRAVY) value indicates the globular (<0 for
            excretion, and toxicity test                       hydrophilic protein) or membranous (>0 for hydrophobic
            Absorption and assimilation through the mouth and   protein) nature of the protein. The value for AMPK1 GRAVY
            digestive  tract, distribution, metabolism, excretion,   was −0.461, whereas the value for AMPK2 GRAVY was
            and toxicity (ADMET) test reveal the pharmacokinetic   −0.295. The SOPMA tool was used to know about the target
            properties of compounds, that is, what the body does with   proteins’ secondary structures (Table 2). AMPK1 has more
            compounds. The application programs OSIRIS Property   α-helixes but fewer β turns and random coil than AMPK2.
            Explorer  and  DruLiTo software  were used to  test  the   The soluble (AMPK1) and transmembrane (AMPK2) nature
            ADMET property of all library compounds [46,47] . According   of the target was identified by SOSUI prediction, software
            to the drug-likeness rules, the log S value estimates solubility   details are given in Table 3.
            whereas the cLogP value tells about the Lipinski rule, total   The soluble (AMPK1) and transmembrane (AMPK2)
            polar surface area (TPSA), molecular mass, drug’s likeness   nature of the target was identified by SOSUI prediction,
            properties (functional portion of ligand), and drug score.   software details are given in Table 3. Followed by validation
            The pharmacodynamics activities of a compound (what the   of the target protein was done by the Ramachandran
            drug does in the body) are predicted by the bioavailability   plot, which shows phi (φ) and psi (ψ) angle and protein


            Volume 2 Issue 3 (2023)                         3                        https://doi.org/10.36922/gpd.0927
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