windows flp internet explorer 8 download

An important issue is how the assembly of the recombination complex from two DNA substrates and four monomeric units of the recombinase is coupled to the spatial and temporal coordination of the ensuing phosphoryl transfer steps. Thus, the relative protein subunit configuration of the tetramer silences the trimers within it by excluding them from assembling a functional active site pair.įlp site-specific recombination provides a useful paradigm for mechanisms of strand breakage and exchange between two DNA molecules mediated by a protein assembly consisting of four recombinase monomers ( Jayaram 1994 Sadowski 1995).

Experiments in which the two models challenge each other reveal that, within the Flp tetramer arranged on a Holliday junction, the two active sites required for its resolution are derived from all four, rather than three, Flp monomers. In the tetramer (or dimer of asymmetric dimers) model, the two active sites are assembled from four Flp monomers, two monomers each contributing one active site. In the trimer model, the two active sites required for each step are assembled from three Flp monomers. Two models for recombination have been proposed. The reaction is carried out in two steps of pairwise strand exchanges by a DNA–protein assembly in which four Flp monomers act cooperatively to execute strand cleavage and joining.

Recombination catalyzed by the Flp site-specific recombinase involves breakage and joining of four DNA strands between two target substrates.

Windows flp internet explorer 8 download