Identifying similar surface patches on proteins using a spin-image surface representation

We apply a spin image representation for 3D objects used in computer vision to the problem of comparing protein surfaces. Due to the irregularities of the protein surfaces, this is a much more complex problem than comparing regular and smooth surfaces. The spin images capture local features in a way that is useful for finding related active sites on the surface of two proteins. They reduce the three-dimensional local information to two dimensions which is a significant computational advantage. We try to find a collection of pairs of points on the two proteins such that the corresponding members of the pairs for one of the proteins form a surface patch for which the corresponding spin images are a “match”. Preliminary results are presented which demonstrate the feasibility of the method.