“…size, shape, polarity, charge, electrostatics, flexibility, secondary structure and hydrogen bonding capabilities) covered by the descriptors exceeds previously reported attempts to physicochemically describe cavities 1,8,9,11,13,18,32. The idea of describing cavities and analysing the cavity property relationships is comparable to the characterisation of small molecules, for example in investigations of molecular diversity39–42 and/or the creation of quantitative structure-activity relationship (QSAR) models 43,44. To explore the structural and physicochemical space of cavities, their key properties were extracted from the descriptor matrix using Principal Component Analysis (PCA).…”