Detection of radiation effects using recombinant bioluminescent Escherichia coli strains

Abstract

Effects of ionizing radiation (0.1-500 Gy) on recombinant Escherichia coli cells containing the stress promoters recA, grpE, or katG, fused to luxCDABE, were characterized by monitoring transcriptional responses reflected by the bioluminescent output. The minimum dose of gamma-irradiation detected by E. coli DPD2794 (recA::luxCDABE) was about 1.5 Gy, while the maximum response was obtained at 200 Gy. The amount of emitted bioluminescence increased proportionally with the gamma-ray doses which were found to elicit a DNA damage response in a range of 1-50 Gy. In addition, the cell growth rate was severely, but transiently, retarded by about 50 Gy. Quantification of the gamma-ray dose may be possible using the recA promoter fusion, since linear enhancement of the bioluminescence emission with increasing gamma-ray dose was observed. Other irradiated strains (50 Gy) responsive to either oxidative stress (DPD2511, katG::luxCDABE) or protein-damaging stress (TV1061, grpE::luxCDABE) did not display an increased bioluminescent output, while DPD2794 irradiated by the same dose of gamma-rays gave a significant bioluminescent output. This indicates that the recA promoter is the one most suitable for developing a biosensor for ionizing radiation.

Bioluminescent bacteria: lux genes as environmental biosensors

“…This new strain (TVA8) was used as a whole-cell reporter for benzene, toluene, ethylbenzene, and xylene (BTEX) sensing and bioavailability determination (2). Novel applications for bacterial luxAB as reporter genes are still being developed, including the use of recombinant E. coli cells containing the stress promoter recA fused to luxCDABE as a biosensor for ionizing radiation (40). In addition, it is possible to use a biosensor to assess changes in effluent toxicity (8,45) rather than monitoring exact toxin concentrations through measurement of bioluminescence quenching.…”

Identification of outer membrane proteins of Vibrio parahaemolyticus and Vibrio alginolyticus altered in response to γ-irradiation or long-term starvation

“…Gamma irradiation causes damage to the DNA of cells (Villavicencio et al, 2004;Lee and Levin, 2008). The types of DNA damage experienced may be: i) direct physical effects of ionizing radiation with primary free radicals, and indirect biochemical effects from reactive oxygen species resulting in double-strand breaks; ii) single-strand breaks; and iii) base pair substituting mutations due to the conversion of pyrimidine bases to 5-(hydroxymethyl) uracil, 5-formyluracil, 5-hydroxycytosine, and 5-hydroxyuracil (Jung, 1997;Lydersen and Pettijohn, 1997;Min et al, 2000) In Gram-negative bacteria, the outer membrane plays an important role in infection and pathogenicity toward the host (Tsolis, 2002). In the outer membrane, proteins play a crucial role during many cellular and physiological processes (Qian et al, 2008).…”

Crude oil degradation efficiency of a recombinantAcinetobacter baumanniistrain and its survival in crude oil-contaminated soil microcosm

“…For better expression there are reports on many bioluminescent reporter bacteria that have been engineered by fusing a lux gene construct under the control of an inducible promoter [14]. Bioluminescences from such fused lux constructs have been used to quantify augmented bacteria in the contaminated environments [14,32]. However, Nunes‐Halldorson and Norma‐Letícia [14], in their review on bioluminescent bacteria suggested that fuse lux gene constructs does not work well for gram‐negative bacteria.…”