Reconstitution of a minimal DNA replicase from Pseudomonas aeruginosa and stimulation by non-cognate auxiliary factors. Journal Article uri icon

Overview

abstract

  • DNA polymerase III holoenzyme is responsible for chromosomal replication in bacteria. The components and functions of Escherichia coli DNA polymerase III holoenzyme have been studied extensively. Here, we report the reconstitution of replicase activity by essential components of DNA polymerase holoenzyme from the pathogen Pseudomonas aeruginosa. We have expressed and purified the processivity factor (beta), single-stranded DNA-binding protein, a complex containing the polymerase (alpha) and exonuclease (epsilon) subunits, and the essential components of the DnaX complex (tau(3)deltadelta'). Efficient primer elongation requires the presence of alphaepsilon, beta, and tau(3)deltadelta'. Pseudomonas aeruginosa alphaepsilon can substitute completely for E. coli polymerase III in E. coli holoenzyme reconstitution assays. Pseudomonas beta and tau(3)deltadelta' exhibit a 10-fold lower activity relative to their E. coli counterparts in E. coli holoenzyme reconstitution assays. Although the Pseudomonas counterpart to the E. coli psi subunit was not apparent in sequence similarity searches, addition of purified E. coli chi and psi (components of the DnaX complex) increases the apparent specific activity of the Pseudomonas tau(3)deltadelta' complex approximately 10-fold and enables the reconstituted enzyme to function better under physiological salt conditions.

publication date

  • March 1, 2005

has subject area

Date in CU Experts

  • October 1, 2013 12:09 PM

Full Author List

  • Jarvis TC; Beaudry AA; Bullard JM; Janjic N; McHenry CS

author count

  • 5

citation count

  • 8

Other Profiles

International Standard Serial Number (ISSN)

  • 0021-9258

Electronic International Standard Serial Number (EISSN)

  • 1083-351X

Additional Document Info

start page

  • 7890

end page

  • 7900

volume

  • 280

issue

  • 9