Colonization of contaminated soil by an introduced bacterium: effects of initial pentachlorophenol levels on the survival of Sphingomonas chlorophenolica strain RA2. Journal Article uri icon



  • The survival of a Sphingomonas species that was introduced into pentachlorophenol (PCP)-contaminated soil was monitored with two complementary methods, a respiration-based assay and a most probable number (MPN) technique. Sphingomonas chlorophenolicastrain RA2 is a PCP-mineralizing bacterium that was introduced into soil contaminated with a range of PCP concentrations (0-300 &mgr;g PCP g(-1) soil). The population of introduced microorganisms was followed for 170 days using a substrate-induced growth-response method and a MPN assay that specifically targets PCP-mineralizing bacteria. Varying the initial PCP concentration resulted in the emergence of three distinct patterns of survival. In soil contaminated with 300 &mgr;g PCP g(-1) the population of S. chlorophenolica strain RA2 immediately declined following introduction, increased by 200-fold and leveled off by the end of the 170-day incubation. In contrast, populations of S. chlorophenolica strain RA2 declined to levels below detection limits in uncontaminated soil by the end of the experiment. Intermediate PCP concentrations (10-100 &mgr;g PCP g(-1) soil) resulted in the establishment of S. chlorophenolica strain RA2 that slowly declined in numbers. These results indicate that Sphingomonas chlorophenolica strain RA2 is an effective colonizer of PCP-contaminated soil but will not persist in the absence of PCP.

publication date

  • October 1, 1999

has restriction

  • bronze

Date in CU Experts

  • November 30, 2016 8:44 AM

Full Author List

  • Colores GM; Schmidt SK

author count

  • 2

Other Profiles

Electronic International Standard Serial Number (EISSN)

  • 1476-5535

Additional Document Info

start page

  • 326

end page

  • 331


  • 23


  • 4-5