Chromosome Methylation and Measurement of Faithful, Once and Only Once per Cell Cycle Chromosome Replication in Caulobacter crescentus

摘要: Caulobacter crescentus exhibits cell-type-specific control of chromosome replication and DNA methylation. Asymmetric cell division yields a replicating stalked nonreplicating swarmer cell. The motile must differentiate into sessile in order to replicate execute asymmetric division. This program implies that initiates the only once per cycle. methylation is restricted predivisional stage, since synthesis produces an unmethylated nascent strand, late also near origin remains hemimethylated longer than located further away. In this report, both assumptions are tested with engineered Tn5-based transposon, Tn5Omega-MP. allows sensitive Southern blot assay measures fully methylated, hemimethylated, duplexes. Tn5Omega-MP was placed at 11 sites around it clearly demonstrated remained One revealed small but detectable amounts duplex cells. Extra second strand. Therefore, measurement critical test "once cycle" rule C. crescentus. Fewer 1 1,000 cells prematurely initiate round replication. implications for very precise negative discussed respect bacterial