Scoring Function Penalty for Pi-Conjugation Disruption
Solution Overview
Problem
Existing scoring functions for estimating binding affinity between ligands and receptors face challenges in accuracy and robustness, particularly in distinguishing active from inactive compounds, and in accurately reflecting physical reality, leading to high numbers of false positives.
Innovation Solution
A computer-implemented method that imposes a penalty for reduced electron delocalization in π-conjugated moieties when docking, using molecular mechanics force fields and quantum chemical methods to assess energy changes, and applies penalties for ligand strain energy and desolvation effects to improve scoring function performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional scoring functions are used to estimate binding affinity, then computational speed is maintained, but accuracy and robustness deteriorate due to inability to accurately reflect physical reality and high false positive rates
Solution Approach 1:
The patent modifies the scoring function by introducing a new parameter that penalizes disruption of π-conjugation in aromatic ligand groups. This parameter change allows the scoring function to more accurately reflect the physical reality of electron delocalization energy, thereby improving binding affinity estimation accuracy without requiring complete redesign of the scoring framework
Solution Approach 2:
The patent segments the binding affinity evaluation into multiple independent components: standard interaction energies and a separate π-conjugation penalty term. This segmentation allows each component to be calculated and optimized independently, improving overall accuracy while maintaining computational tractability
2Productivity
If scoring functions are simplified for computational efficiency, then processing speed is improved, but the ability to distinguish active from inactive compounds deteriorates
Solution Approach 1:
The patent introduces an intermediary penalty term that mediates between computational efficiency and accuracy. The π-conjugation penalty is calculated using a straightforward geometric criterion based on torsion angles, which is computationally inexpensive yet effectively distinguishes active compounds that maintain aromatic conjugation from inactive compounds that disrupt it
3Measurement precision
If empirical scoring functions are used based on complex geometry evaluation, then fitting to experimental data is improved, but false positive rates increase due to inability to account for electron delocalization energy
Solution Approach 1:
The patent converts the previously overlooked disruption of π-conjugation, which was causing false positives, into a beneficial penalty term. By explicitly accounting for the energy cost of disrupting electron delocalization in aromatic groups, the scoring function now correctly penalizes inactive compounds that falsely appear active due to favorable geometric arrangements that disrupt conjugation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method significantly reduces false positives by accurately discriminating between active and inactive compounds, achieving scores close to experimental binding affinities and improving the overall performance of scoring functions in structure-based drug design.
Implementation Method 1
using molecular mechanics force fields and quantum chemical methods to assess energy changes
Implementation Method 2
using molecular mechanics force fields and quantum chemical methods to assess energy changes
Implementation Method 3
applies penalties for ligand strain energy and desolvation effects to improve scoring function performance
Data Source
Figure 1
AI summary
A method of scoring binding affinity of a proposed ligand molecule for a receptor molecule using computer analysis and computer data bases to account for the increase in energy required where docking disrupts or partially disrupts the p-conjugated character of the ligand when bound to the receptor. The method uses data representing one or more proposed ligand molecules to be scored and data representing the receptor molecule. If the predicted ligand- receptor structure adopts a geometry characterized by less delocalization across a p-conjugated ligand moiety, a penalty is imposed.