Genome-wide analysis of E. coli MukB distribution using ChIP-sequencing. Escherichia coli K-12

Paper abstract : The Escherichia coli SMC complex, MukBEF, interacts with the ParC subunit of topoisomerase IV (TopoIV), consistent with sequential roles in chromosome unlinking and segregation. Although clusters of MukBEF molecules are normally associated with the chromosome replication origin region (ori), we demonstrate their association with the replication termination region (ter), which is enhanced when ATP hydrolysis by MukB is impaired. We show that MukBEF interacts in vivo and in vitro with MatP, which binds matS sites in ter. The MatP-MukBEF interaction limits the stable association of MukBEF complexes with ter and the availability of functional TopoIV during decatenation of sister ters. The MukBEF-TopoIV interaction is influenced by the nucleotide state of MukBEF. The combined action of MukBEF and MatP helps position MukBEF clusters in relation to the chromosome, thereby, influencing chromosome organization and segregation. Finally, we demonstrate that the regulated sequential action of TopoIV and MukBEF promotes chromosome decatenation and segregation. Overall design: ChIP-seq profiles of E. coli MukB and ATPase-deficient MukBEQ and MukBDA mutants in triplicates. ChIP-seq of MukB and MukBEQ have been done in wild-type and ∆matP strain. ChIP-seq profiles of MatP in triplicates