MycPermCheck: The Mycobacterium tuberculosis permeability prediction tool for small molecules SUPPLEMENT S3: DESCRIPTION AND EVALUATION OF PADEL-DESCRIPTOR BASED MODEL Descriptor selection

As an alternative to the QikProp model, which is based on the commercial Schrödinger software, an additional regression model was derived. This model is based solely on descriptors of the open-source descriptor calculation package PaDEL-Descriptor (Yap, 2011). Since PaDEL provides descriptors in an overwhelming quantity (863 descriptors), a first approach of selecting a feasible combination of descriptors was the search for QikProp-equivalents within the PaDEL inventory. In this attempt, the following descriptors were chosen (p < 0.001, Mann-Whitney-U tests of Actives against ZINC):