arXiv Machine Learning

Benchmarking Peptide-Protein Affinity Prediction Across Peptide and Target Shifts

arXiv Machine Learning
Oct 5

Beyond Random Splits: Evaluating Drug-Target Affinity Models Under Chemically and Biologically Motivated Distribution Shifts Copy

The study investigates how different distribution shifts affect the evaluation of drug‑target affinity (DTA) models, using 718,800 drug‑protein pairs from ChEMBL and BindingDB. It compares a baseline Morgan‑fingerprint + protein‑CNN model with 12 architectures that combine four drug representations and three ESM‑2 interaction modes, finding that mean validation RMSE rises significantly under protein‑cluster and dual out‑of‑distribution (OOD) scenarios. Model rankings remain consistent across chemical shifts but diverge under protein and dual OOD, indicating that architecture selection depends on the specific extrapolation context rather than just average error or training‑set size. Why it matters: The results suggest that DTA benchmarks should be designed to reflect the chemical and target shifts expected in real deployment, ensuring that chosen models perform reliably when applied to new chemical series or protein targets.

By Minjae Chung, Clara Li, Malar Paavai Muthukumaran, Shaunna Wang, Aniket Ramkrishnan Iyer, Shaun Qien Yeau Tan, Harinishree Sathu, Micky C. Nnamdi, J. Ben Tamo, Benoit Louis Marteau, May Dongmei Wang
arXiv AI
Sep 25

CaliPPer: quantifying, predicting and improving AI model performance for binding prediction

CaliPPer is a post‑hoc framework that calibrates and predicts the performance of binding‑prediction models by combining a multi‑chain Sample‑to‑Domain Distance (S2DD) metric with distance‑aware Bayesian recalibration. It operates at three resolutions—generalisability score, aggregate performance prediction, and per‑sample confidence—achieving strong distance‑performance correlations (|r| = 0.80–0.92) and low prediction errors for AUROC, AP, and F1. In retrospective analyses of five published studies, CaliPPer increased true discovery rates, improving AUROC by up to +0.20 on unseen epitopes and variants and raising confirmed neoantigen findings from 0/5 to 3/5.

By Jian-Qing Zheng, Hantao Lou, Zinan Yin, Sam Farrar, Yuze Zhou, Elie Antoun, Xiangxi Wang, Xuetao Cao, Tao Dong
arXiv Machine Learning
Sep 22

DPTM-DT: Dual-Pretrained Transformer Multitask Representation Learning for Drug-Target Prediction

The paper introduces DPTM‑DT, a dual‑pretrained Transformer framework that integrates GROVER molecular graph embeddings, ESM protein language‑model embeddings, and CTD physicochemical descriptors for drug‑target prediction. It employs bidirectional cross‑modal attention to share drug‑target information and uses a single pair representation for continuous affinity regression, high‑affinity binary classification, and six‑level affinity classification. Experiments on Davis and KIBA datasets show that DPTM‑DT outperforms existing methods across regression, binary, and multiclass tasks, with ablation studies confirming the contributions of dual target representation, gated fusion, and cross‑modal attention.

By Ge Kong
arXiv Machine Learning
Oct 21

Ensemble-Aware Structural Encoding (EASE): Conditioning Protein Encoders on Peptide Conformational Ensembles

Ensemble-Aware Structural Encoding (EASE) is a new framework that conditions protein encoders on peptide conformational ensembles rather than single sequences or structures. By selecting central conformers that capture a peptide’s major structural states and fusing their representations with a permutation‑invariant operator, EASE produces a peptide‑level representation that better reflects conformational variability. In evaluations on six peptide property‑prediction tasks, EASE consistently outperforms single‑structure baselines, achieving an average absolute gain of about 3.0% and improving further as more conformers are incorporated.

By Ruoyao Zhang, Hongxuan Li, Jie Peng, Tianlong Chen
arXiv AI
Jul 29

Beyond Predictive Accuracy: A Reliability-Aware Audit of Molecular Representations for Human Olfaction

arXiv:2607. 24848v1 Announce Type: cross Abstract: Pretrained molecular encoders are commonly evaluated through downstream prediction, but predictive accuracy alone does not establish that a learned representation captures reproducible scientific structure, adds information beyond strong conventional baselines, or transfers out of distribution.

By Kai Lun Huang (California State University, Fullerton), Wei Chieh Sun (University of Washington)