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. 1995 Aug;61(8):2950–2957. doi: 10.1128/aem.61.8.2950-2957.1995

Characterization of rhizosphere colonization by luminescent Enterobacter cloacae at the population and single-cell levels.

E A Rattray 1, J I Prosser 1, L A Glover 1, K Killham 1
PMCID: PMC167571  PMID: 7487027

Abstract

A bioluminescence marker system was used to characterized colonization of the rhizosphere by a bacterial inoculum, both in terms of population activity and at the single-cell level. Plasmid pQF70/44, which contains luxAB genes under the control of a strong constitutive phage promoter, was introduced into the rhizobacterium and model biocontrol agent Enterobacter cloacae. Light output from the lux-modified strain was detected by luminometry of samples from growing cultures of E. cloacae and from inoculated soil and wheat root samples. The minimum detection limits for fully active cells under optimum conditions were 90 and 445 cells g-1 for liquid culture and soil, respectively. The metabolic activities of the lux-marked population of E. cloacae, characterized by luminometry, contrasted in rhizosphere and nonrhizosphere soil. Cells in the rhizosphere were active, and there was a linear relationship between light output and cell concentration. The activity of cells in nonrhizosphere coil could not be detected unless the soil was supplied with substrate. Novel use of a charge-coupled device is reported for the spatial characterization of rhizosphere colonization by E. cloacae (pQF70/44) at the single-cell and population levels. Used macroscopically, the charge-coupled device identified differences in colonization due to competition from indigenous soil organisms. The lux-marked bacterium was able to colonize all depths of roots in the absence of competition but was restricted tot he spermosphere in the presence of competition (nonsterile soil).(ABSTRACT TRUNCATED AT 250 WORDS)

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Selected References

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  1. Bale M. J., Fry J. C., Day M. J. Plasmid transfer between strains of Pseudomonas aeruginosa on membrane filters attached to river stones. J Gen Microbiol. 1987 Nov;133(11):3099–3107. doi: 10.1099/00221287-133-11-3099. [DOI] [PubMed] [Google Scholar]
  2. Connor J. A. Digital imaging of free calcium changes and of spatial gradients in growing processes in single, mammalian central nervous system cells. Proc Natl Acad Sci U S A. 1986 Aug;83(16):6179–6183. doi: 10.1073/pnas.83.16.6179. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Cook N., Silcock D. J., Waterhouse R. N., Prosser J. I., Glover L. A., Killham K. Construction and detection of bioluminescent strains of Bacillus subtilis. J Appl Bacteriol. 1993 Oct;75(4):350–359. doi: 10.1111/j.1365-2672.1993.tb02787.x. [DOI] [PubMed] [Google Scholar]
  4. Mandel M., Higa A. Calcium-dependent bacteriophage DNA infection. J Mol Biol. 1970 Oct 14;53(1):159–162. doi: 10.1016/0022-2836(70)90051-3. [DOI] [PubMed] [Google Scholar]
  5. Meikle A., Killham K., Prosser J. I., Glover L. A. Luminometric measurement of population activity of genetically modified Pseudomonas fluorescens in the soil. FEMS Microbiol Lett. 1992 Dec 1;78(2-3):217–220. doi: 10.1016/0378-1097(92)90029-n. [DOI] [PubMed] [Google Scholar]
  6. Paau A. S. Improvement of Rhizobium inoculants. Appl Environ Microbiol. 1989 Apr;55(4):862–865. doi: 10.1128/aem.55.4.862-865.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Prosser J. I. Molecular marker systems for detection of genetically engineered micro-organisms in the environment. Microbiology. 1994 Jan;140(Pt 1):5–17. doi: 10.1099/13500872-140-1-5. [DOI] [PubMed] [Google Scholar]
  8. Rattray E. A., Prosser J. I., Killham K., Glover L. A. Luminescence-based nonextractive technique for in situ detection of Escherichia coli in soil. Appl Environ Microbiol. 1990 Nov;56(11):3368–3374. doi: 10.1128/aem.56.11.3368-3374.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Shaw J. J., Dane F., Geiger D., Kloepper J. W. Use of bioluminescence for detection of genetically engineered microorganisms released into the environment. Appl Environ Microbiol. 1992 Jan;58(1):267–273. doi: 10.1128/aem.58.1.267-273.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Silcock D. J., Waterhouse R. N., Glover L. A., Prosser J. I., Killham K. Detection of a single genetically modified bacterial cell in soil by using charge coupled device-enhanced microscopy. Appl Environ Microbiol. 1992 Aug;58(8):2444–2448. doi: 10.1128/aem.58.8.2444-2448.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Stewart G. S., Williams P. lux genes and the applications of bacterial bioluminescence. J Gen Microbiol. 1992 Jul;138(7):1289–1300. doi: 10.1099/00221287-138-7-1289. [DOI] [PubMed] [Google Scholar]
  12. Waterhouse R. N., Silcock D. J., White H. L., Buhariwalla H. K., Glover L. A. The cloning and characterization of phage promoters, directing high expression of luciferase in Pseudomonas syringae pv. phaseolicola, allowing single cell and microcolony detection. Mol Ecol. 1993 Oct;2(5):285–293. doi: 10.1111/j.1365-294x.1993.tb00021.x. [DOI] [PubMed] [Google Scholar]
  13. Weller D. M. Distribution of a Take-All Suppressive Strain of Pseudomonas fluorescens on Seminal Roots of Winter Wheat. Appl Environ Microbiol. 1984 Oct;48(4):897–899. doi: 10.1128/aem.48.4.897-899.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Winstanley C., Morgan J. A., Pickup R. W., Jones J. G., Saunders J. R. Differential regulation of lambda pL and pR promoters by a cI repressor in a broad-host-range thermoregulated plasmid marker system. Appl Environ Microbiol. 1989 Apr;55(4):771–777. doi: 10.1128/aem.55.4.771-777.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. de Weger L. A., Dunbar P., Mahafee W. F., Lugtenberg B. J., Sayler G. S. Use of Bioluminescence Markers To Detect Pseudomonas spp. in the Rhizosphere. Appl Environ Microbiol. 1991 Dec;57(12):3641–3644. doi: 10.1128/aem.57.12.3641-3644.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]

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