Revisiting the Voronoi Description of Protein-Protein Interfaces: Algorithms

Describing macro-molecular interfaces is key to improve our understanding of the specificity and of the stability of macro-molecular interactions, and also to predict complexes when little structural information is known. Ideally, an interface model should provide easy-tocompute geometric and topological parameters exhibiting a good correlation with important bio-physical quantities. It should also be parametric and amenable to comparisons. In this spirit, we recently developed an interface model based on Voronoi diagrams, which proved instrumental to refine state-of-the-art conclusions and provide new insights. This paper formally presents this Voronoi interface model. First, we discuss its connexion to classical interface models based on distance cut-offs and solvent accessibility. Second, we develop the geometric and topological constructions underlying the Voronoi interface, and design efficient algorithms based on the Delaunay triangulation and the α-complex. We conclude with perspectives. In particular, we expect the Voronoi interface model to be particularly well suited for the problem of comparing interfaces in the context of large-scale structural studies.