The rise of state-centric biophysics: integrating orthogonal molecular readouts across biophysical scales

Abstract

Abstract Modern biophysics has evolved from the measurement of isolated molecular properties toward increasingly integrated molecular characterization. Advances in instrumentation, orthogonal workflows, and multidimensional analytical platforms have expanded the breadth of molecular information obtainable from a single experimental context, increasing what we define here as “information density”. In this review, we examine the scientific and technological forces underlying this transition and propose state-centric biophysics as an interpretive framework in which biophysical properties like affinity, kinetics, thermodynamics, stability, structural dynamics, hydrodynamics, ligand occupancy, and assembly state are viewed as complementary descriptors of a shared molecular-state landscape rather than as independent experimental outputs. Representative case studies, including targeted protein degradation, molecular glues, Heat Shock Protein 90 (HSP90) molecular cycle and inhibition, and state-selective inhibition of Kirsten Rat Sarcoma Viral Oncogene Homolog G12C (KRAS G12C), illustrate how biological activity frequently depends on molecular-state properties that extend beyond ligand occupancy alone. Collectively, these observations suggest that the central challenge of modern biophysics is increasingly shifting from measuring molecular properties to identifying the molecular states that govern mechanism, efficacy, selectivity, and therapeutic response.