Structural and energetic determinants of the S1-site specificity in serine proteases

In recent years the number of determined three-dimensional structures of serine proteases that are accompanied by detailed mutational studies has grown rapidly. In particular, spatial structures have been described for enzymes involved in processes of critical medical significance, often related to severe pathophysiological diseases. There has also been significant progress in the understanding of the structural grounds for the substrate specificity of serine proteases. This review is concerned mainly with primary structural determinants of the S1 specificity, the crucial component of substrate selectivity, often in relation to more distant specificity elements, which cooperatively influence the S1 site.