scholarly journals Computational Characterization of Small Molecules Binding to the Human XPF Active Site and Virtual Screening to Identify Potential New DNA Repair Inhibitors Targeting the ERCC1-XPF Endonuclease

2018 ◽  
Vol 19 (5) ◽  
pp. 1328 ◽  
Author(s):  
Francesco Gentile ◽  
Khaled Barakat ◽  
Jack Tuszynski
2007 ◽  
Vol 101 (7) ◽  
pp. 1043-1048 ◽  
Author(s):  
Boris Bleijlevens ◽  
Tara Shivarattan ◽  
Barbara Sedgwick ◽  
Stephen E.J. Rigby ◽  
Steve J. Matthews

2020 ◽  
Vol 16 (5) ◽  
pp. 583-598 ◽  
Author(s):  
Hina Shamshad ◽  
Abdul Hafiz ◽  
Ismail I. Althagafi ◽  
Maria Saeed ◽  
Agha Zeeshan Mirza

Background: Human African trypanosomiasis is a fatal disease prevalent in approximately 36 sub-Saharan countries. Emerging reports of drug resistance in Trypanosoma brucei are a serious cause of concern as only limited drugs are available for the treatment of the disease. Pteridine reductase is an enzyme of Trypanosoma brucei. Methods: It plays a critical role in the pterin metabolic pathway that is absolutely essential for its survival in the human host. The success of finding a potent inhibitor in structure-based drug design lies within the ability of computational tools to efficiently and accurately dock a ligand into the binding cavity of the target protein. Here we report the computational characterization of Trypanosoma brucei pteridine reductase (Tb-PR) active-site using twenty-four high-resolution co-crystal structures with various drugs. Structurally, the Tb-PR active site can be grouped in two clusters; one with high Root Mean Square Deviation (RMSD) of atomic positions and another with low RMSD of atomic positions. These clusters provide fresh insight for rational drug design against Tb-PR. Henceforth, the effect of several factors on docking accuracy, including ligand and protein flexibility were analyzed using Fred. Results: The online server was used to analyze the side chain flexibility and four proteins were selected on the basis of results. The proteins were subjected to small-scale virtual screening using 85 compounds, and statistics were calculated using Bedroc and roc curves. The enrichment factor was also calculated for the proteins and scoring functions. The best scoring function was used to understand the ligand protein interactions with top common compounds of four proteins. In addition, we made a 3D structural comparison between the active site of Tb-PR and Leishmania major pteridine reductase (Lm- PR). We described key structural differences between Tb-PR and Lm-PR that can be exploited for rational drug design against these two human parasites. Conclusion: The results indicated that relying just on re-docking and cross-docking experiments for virtual screening of libraries isn’t enough and results might be misleading. Hence it has been suggested that small scale virtual screening should be performed prior to large scale screening.


2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Stephanie Sun ◽  
Kavya Anand ◽  
Ishani Ashok ◽  
Bhavesh Ashok ◽  
Ayush Bajaj ◽  
...  

In December of 2019, a novel coronavirus was first identified in Wuhan, China, and has since spread around the world, leaving a largely unsolved biomedical problem in its wake. Upon entry into host cells, the main protease is essential for the replication of viral RNA, which is what allows the virus to replicate inside humans. Inhibition of the main protease has been investigated as a potential strategy for inhibition of the viral replication cycle. Here, we designed a combinatorial library of small molecules and performed high-throughput virtual screening to identify a series of hit compounds that may serve as potential inhibitors of the main protease. In our design of covalent inhibitors of the coronavirus protease, we modeled a library of 361 peptidomimetic Michael acceptor small molecules, which are designed to engage the nucleophilic cysteine residue in the active site of the protease in an irreversible 1,4-conjugate addition. We then employed a variety of computational tools to determine the binding affinity of our designed compounds when bound to the protease active site, where we determined that cationic side chains are potentially beneficial for inhibition of SARS-CoV-2.   


1986 ◽  
Vol 56 (03) ◽  
pp. 349-352 ◽  
Author(s):  
A Tripodi ◽  
A Krachmalnicoff ◽  
P M Mannucci

SummaryFour members of an Italian family (two with histories of venous thromboembolism) had a qualitative defect of antithrombin III reflected by normal antigen concentrations and halfnormal antithrombin activity with or without heparin. Anti-factor Xa activities were consistently borderline low (about 70% of normal). For the propositus’ plasma and serum the patterns of antithrombin III in crossed-immunoelectrophoresis with or without heparin were indistinguishable from those of normal plasma or serum. A normal affinity of antithrombin III for heparin was documented by heparin-sepharose chromatography. Affinity adsorption of the propositus’ plasma to human α-thrombin immobilized on sepharose beads revealed defective binding of the anti thrombin III to thrombin-sepharose. Hence the molecular defect of this variant appears to be at the active site responsible for binding and neutralizing thrombin, thus accounting for the low thrombin inhibitory activity.


Sign in / Sign up

Export Citation Format

Share Document