Deletion of the parA (soj) Homologue in Pseudomonas aeruginosa Causes ParB Instability and Affects Growth Rate, Chromosome Segregation, and Motility

Research output: Contribution to journalArticle


  • K Lasocki
  • AA Bartosik
  • J Mierzejewska
  • Chris Thomas
  • G Jagura-Burdzy

Colleges, School and Institutes


The parA and parB genes of Pseudomonas aeruginosa are located approximately 8 kb anticlockwise from oriC. ParA is a cytosolic protein present at a level of around 600 molecules per cell in exponential phase, but the level drops about fivefold in stationary phase. Overproduction of full-length ParA or the N-terminal 85 amino acids severely inhibits growth of P. aeruginosa and P. putida. Both inactivation of parA and overexpression of parA in trans in P. aeruginosa also lead to accumulation of anucleate cells and changes in motility. Inactivation of parA also increases the turnover rate (degradation) of ParB. This may provide a mechanism for controlling the level of ParB in response to the growth rate and expression of the parAB operon.


Original languageEnglish
Pages (from-to)5762-5772
Number of pages11
JournalJournal of Bacteriology
Issue number15
Early online date1 Jun 2007
Publication statusPublished - 1 Jun 2007