The phage Mu transpososome core: DNA requirements for assembly and function.

摘要: The two chemical steps of phage Mu transpositional recombination, donor DNA cleavage and strand transfer, take place within higher order protein-DNA complexes called transpososomes. At the core these is a tetramer MuA (the transposase), bound to ends genome. While transpososome assembly normally requires number cofactors, under certain conditions only short fragment are required. requirements for this process, as well stability activity ensuing complexes, were established. divalent cation required stable complex could be omitted if substrate was prenicked, flanking very or strands non-complementary. presence single nucleotide beyond genome end on non-cut critical stability. Donor additionally at least nucleotides cleaved. double helix destabilized, implying distortion near active site. Although Mg2+, transfer took in Ca2+ well, suggesting conformational difference site steps.