P1 plasmid segregation: accurate redistribution by dynamic plasmid pairing and separation.

ABSTRACT: Low-copy-number plasmids, such as P1 and F, encode a type Ia partition system (P1par or Fsop) for active segregation of copies to daughter cells. Typical descriptions show a single central plasmid focus dividing and the products moving to the cell quarter regions, ensuring segregation. However, using improved optical and analytical tools and large cell populations, we show that P1 plasmid foci are very broadly distributed. Moreover, under most growth conditions, more than two foci are frequently present. Each focus contains either one or two plasmid copies. Replication and focus splitting occur at almost any position in the cell. The products then move rapidly apart for approximately 40% of the cell length. They then tend to maintain their relative positions. The segregating foci often pas

SUBMITTER: Sengupta M 

PROVIDER: S-EPMC2820840 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature