Special Mathematics Department Colloquium Mariel Vazquez UC Berkeley "Topological analysis of enzymatic actions: site-specific recombinases and topoisomerases" Thursday, February 17, 2005 4:15pm in JWB 335 DNA topology is the study of geometrical (supercoiling) and topological(knotting) properties of DNA loops and circular DNA molecules. Virtually every reaction involving DNA is influenced by DNA topology, or has topological effects. Site-specific recombinases and topoisomerases are enzymes able to change the topology of circular DNA by breaking the DNA and introducing one or more crossing changes. Mathematical analysis of such changes may provide relevant information about the possible enzymatic pathways, and about DNA conformation at the moment of double-stranded break induction. In this talk I will discuss some of the problems that I am currently interested in, and the topological and computational tools used in their analyses.