Bioluminescence induction response and survival of the bioreporter bacterium Pseudomonas fluorescens HK44 in nutrient-deprived conditions

Matrubutham, Udayakumar; Thonnard, J. E.; Sayler, Gary S.

doi:10.1007/s002530050981

“…The lux cassette insertion blocks expression of the downstream genes for salicylate degradation, preventing plasmid‐mediated growth of HK44 on naphthalene or salicylate. HK44 is able to degrade salicylate via a pathway encoded by chromosomal genes [ Matrubutham et al , 1997], but we found that salicylate is neither consumed nor supports growth of HK44 over 12–20 hours after addition to glucose‐grown cultures (data not shown). Earlier work in our laboratory developed a model relating HK44's inducible bioluminescence response to population density in a porous medium under hydrostatic nongrowth conditions [ Uesugi et al , 2001] and during growth under unsaturated‐flow conditions [ Yarwood et al , 2002].…”

Section: Methodsmentioning

confidence: 80%

Impact of microbial growth on water flow and solute transport in unsaturated porous media

Yarwood

¹

,

Rockhold

²

,

Niemet

³

et al. 2006

Water Resources Research

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[1] A novel analytical method was developed that permitted real-time, noninvasive measurements of microbial growth and associated changes in hydrodynamic properties in porous media under unsaturated flowing conditions. Salicylate-induced, lux gene-based bioluminescence was used to quantify the temporal and spatial development of colonization over a 7-day time course. Water contents were determined daily by measuring light transmission through the system. Hydraulic flow paths were determined daily by pulsing a bromophenol blue dye solution through the colonized region of the sand. Bacterial growth and accumulation had a significant impact on the hydraulic properties of the porous media. Microbial colonization caused localized drying within the colonized zone, with decreases in saturation approaching 50% of antecedent values, and a 25% lowering of the capillary fringe height. Flow was retarded within the colonized zone and diverted around it concurrent with the expansion of the colonized zone between days 3 and 6. The location of horizontal dispersion corresponded with the cell densities of 1-3 Â 10 9 cells g À1 dry sand. The apparent solute velocity through the colonized region was reduced from 0.41 cm min À1 (R 2 = 0.99) to 0.25 cm min À1 (R 2 = 0.99) by the sixth day of the experiment, associated with population densities that would occupy approximately 7% of the available pore space within the colonized region. Changes in the extent of colonization occurred over the course of the experiment, including upward migration against flow. The distribution of cells was not determined by water flow alone, but rather by a dynamic interaction between water flow and microbial growth. This experimental system provides rich data sets for the testing of conceptualizations expressed through numerical modeling.

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“…Such reporters have been widely used for tracking and monitoring microorganisms in the environment because they are easy to detect and are non-ubiquitous in soil. There are several reports indicating the use of genes encoding lux [17] to track the presence of Pseudomonas, Rhizobium, and many plant pathogens in the environment [6,18,19]. The lux genes are potentially innocuous to the indigenous gene pool, unique to the GMOs, assayed easily and rapidly, and supposed to pose a little metabolic burden on the host cells [14,20].…”

Section: Introductionmentioning

confidence: 99%

Crude oil degradation efficiency of a recombinant Acinetobacter baumannii strain and its survival in crude oil-contaminated soil microcosm

Mishra¹,

Sarma

²

,

Lal

³

2004

FEMS Microbiology Letters

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A hydrocarbon degrading Acinetobacter baumannii S30 strain, isolated from crude oil-contaminated soil, was inserted with the lux gene from the luciferase gene cassette luxCDABE. Soil microcosms were designed to study the degradation efficacy for total petroleum hydrocarbon (TPH) of crude oil by lux-tagged A. baumannii S30 pJES. Bioaugmentation of a TPH-contaminated microcosm with A baumannii S30 pJES showed that TPH levels were reduced from 89.3 to 53.9 g/kg soil in 90 days. Biodegradation of TPH by A baumannii S30 pJES was also monitored in shake flask conditions, which showed a reduction of initial TPH levels by over 50% at the end of 120 h. A lux-PCR-based approach along with the standard dilution plating with selective antibiotics was successfully utilized to monitor the survivability of the lux-tagged strain A. baumannii S30 pJES in soil microcosms and stability of the lux insert in the host strain A. baumannii S30. The selective plating technique indicated the population of A. baumannii S30 pJES to be 6.5+/-0.13 x 10(8) CFU/g at day zero (just after bioaugmentation) and 2.09+/-0.08 x 10(8) CFU/g of soil after 90 days of incubation. lux-PCR confirmed the stability of the insert in all the randomly selected colonies of A. baumannii strains from the antibiotic plates. The lux insert was stable after 50 generations in Luria Bertini broth and storage at -70 degrees C as glycerol stocks for over a year. These results revealed that the lux insert was stable and lux-tagged A. baumannii S30 strain could survive in a TPH-contaminated soil microcosm and could degrade TPH in the soil microcosm conditions. It can be used as an effective marker to monitor the survival of augmented strains at a bioremediation site.

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“…Such reporters have been widely used for tracking and monitoring microorganisms in the environment because they are easy to detect and are non‐ubiquitous in soil. There are several reports indicating the use of genes encoding lux [17] to track the presence of Pseudomonas, Rhizobium , and many plant pathogens in the environment [6,18,19]. The lux genes are potentially innocuous to the indigenous gene pool, unique to the GMOs, assayed easily and rapidly, and supposed to pose a little metabolic burden on the host cells [14,20].…”

Section: Introductionmentioning

confidence: 99%

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

Mishra¹,

Sarma²,

Lal

³

2004

FEMS Microbiology Letters

View full text Add to dashboard Cite

A hydrocarbon degrading Acinetobacter baumannii S30 strain, isolated from crude oil-contaminated soil, was inserted with the lux gene from the luciferase gene cassette luxCDABE. Soil microcosms were designed to study the degradation efficacy for total petroleum hydrocarbon (TPH) of crude oil by lux-tagged A. baumannii S30 pJES. Bioaugmentation of a TPH-contaminated microcosm with A baumannii S30 pJES showed that TPH levels were reduced from 89.3 to 53.9 g/kg soil in 90 days. Biodegradation of TPH by A baumannii S30 pJES was also monitored in shake flask conditions, which showed a reduction of initial TPH levels by over 50% at the end of 120 h. A lux-PCR-based approach along with the standard dilution plating with selective antibiotics was successfully utilized to monitor the survivability of the lux-tagged strain A. baumannii S30 pJES in soil microcosms and stability of the lux insert in the host strain A. baumannii S30. The selective plating technique indicated the population of A. baumannii S30 pJES to be 6.5+/-0.13 x 10(8) CFU/g at day zero (just after bioaugmentation) and 2.09+/-0.08 x 10(8) CFU/g of soil after 90 days of incubation. lux-PCR confirmed the stability of the insert in all the randomly selected colonies of A. baumannii strains from the antibiotic plates. The lux insert was stable after 50 generations in Luria Bertini broth and storage at -70 degrees C as glycerol stocks for over a year. These results revealed that the lux insert was stable and lux-tagged A. baumannii S30 strain could survive in a TPH-contaminated soil microcosm and could degrade TPH in the soil microcosm conditions. It can be used as an effective marker to monitor the survival of augmented strains at a bioremediation site.

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Bioluminescence induction response and survival of the bioreporter bacterium Pseudomonas fluorescens HK44 in nutrient-deprived conditions

Cited by 23 publications

References 11 publications

Impact of microbial growth on water flow and solute transport in unsaturated porous media

Impact of microbial growth on water flow and solute transport in unsaturated porous media

Crude oil degradation efficiency of a recombinant Acinetobacter baumannii strain and its survival in crude oil-contaminated soil microcosm

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

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