Construction and use of specific luminescent recombinant bacterial sensors for the assessment of bioavailable fraction of cadmium, zinc, mercury and chromium in the soil

Abstract Recombinant luminescent bacterial sensors for the detection of zinc [MC1061(pzntRluc)] and chromate [AE104(pchrBluc)] were constructed. The sensors carry firefly luciferase gene as a reporter under the control of zinc-inducible regulatory unit from Zn resistance system in chromosomal DNA of Escherichia coli or chromate-inducible unit from Ralstonia metallidurans CH34 megaplasmid pMOL28. The response of the sensors was calibrated using Zn 2+ , Cr 2 O 7 2− and CrO 4 2− , respectively. The detection limit of the zinc sensor for zinc was 40 μM (2.6 mg l −1 of Zn) and that of chromate sensor for dichromate 30 nM (1.6 μg l −1 of Cr) and for chromate 50 nM (2.6 μg l −1 of Cr), respectively. The specificity of the two above-mentioned sensors constructed in this study and a mercury-inducible bacterial sensor MC1061(pmerBR BS luc) constructed by us earlier [Anal. Chem. 73 (2001) 5168] was determined by using different heavy metal compounds. The zinc and mercury sensors were not completely specific to the target metals. The zinc sensor was co-inducible with cadmium and mercury and the mercury sensor with cadmium. The chromate sensor was inducible not only by chromate but also with Cr 3+ . The bacterial sensors constructed were used for the estimation of bioavailable fraction of heavy metals in soils spiked with different amounts of zinc, cadmium, mercury and chromate. Both soil–water suspensions and soil–water extracts were analyzed. The results showed that the majority of heavy metals remained adsorbed to soil particles: only 0.6% of Cd, 1.3% of Hg, 2% of Zn and 46% of Cr (VI) were available to the bacterial sensors in soil–water extracts. However, when the soil–water suspensions were analyzed, approximately 20 times more cadmium and 30 times more mercury (12 and 40%, respectively) was available for the sensor bacteria whereas the available fractions of zinc and chromate in soil–water extract and suspension were similar. Thus, this study showed that in case of cadmium and mercury (but not zinc and chromium) the particle-bound metals were also partially bioavailable.

[1]  M. Karp,et al.  Nitric oxide donor-mediated killing of bioluminescent Escherichia coli , 1994, Antimicrobial Agents and Chemotherapy.

[2]  W. J. Dower,et al.  High efficiency transformation of E. coli by high voltage electroporation , 1988, Nucleic Acids Res..

[3]  S. Silver,et al.  Plasmid chromate resistance and chromate reduction. , 1992, Plasmid.

[4]  B. Mitra,et al.  Escherichia coli Soft Metal Ion-translocating ATPases* , 2000, The Journal of Biological Chemistry.

[5]  M Virta,et al.  Luminescent bacterial sensor for cadmium and lead. , 1998, Biosensors & bioelectronics.

[6]  J. Sambrook,et al.  Molecular Cloning: A Laboratory Manual , 2001 .

[7]  M. Karp,et al.  Comparison of gram positive and gram negative bacterial strains cloned with different types of luciferase genes in bioluminescence cytotoxicity tests , 1995 .

[8]  R. C. Rychert,et al.  Inhibition of bioluminescence in a recombinant Escherichia coli , 1991 .

[9]  D. Kobayashi,et al.  Improved broad-host-range plasmids for DNA cloning in gram-negative bacteria. , 1988, Gene.

[10]  L. Diels,et al.  Bacterial biosensors for the toxicity assessment of solid wastes , 1996 .

[11]  T. O’Halloran,et al.  DNA Distortion Mechanism for Transcriptional Activation by ZntR, a Zn(II)-responsive MerR Homologue in Escherichia coli * , 1999, The Journal of Biological Chemistry.

[12]  G. Welp Inhibitory effects of the total and water-soluble concentrations of nine different metals on the dehydrogenase activity of a loess soil , 1999, Biology and Fertility of Soils.

[13]  Steve P. McGrath,et al.  Response of a Rhizobium-based luminescence biosensor to Zn and Cu in soil solutions from sewage sludge treated soils , 2000 .

[14]  S. Cohen,et al.  Analysis of gene control signals by DNA fusion and cloning in Escherichia coli. , 1980, Journal of molecular biology.

[15]  M Virta,et al.  Detection of organomercurials with sensor bacteria. , 2001, Analytical chemistry.

[16]  C. Blaise,et al.  Cyst‐based ecotoxicological tests using Anostracans: Comparison of two species of Streptocephalus , 1994 .

[17]  Jennifer C. Lewis,et al.  Peer Reviewed: Applications of Reporter Genes , 1998 .

[18]  M. Mergeay,et al.  Electroporation of Alcaligenes eutrophus with (mega) plasmids and genomic DNA fragments , 1994, Applied and environmental microbiology.

[19]  M Mergeay,et al.  luxAB gene fusions with the arsenic and cadmium resistance operons of Staphylococcus aureus plasmid pI258. , 1993, FEMS microbiology letters.

[20]  Marko Virta,et al.  A Luminescence-Based Mercury Biosensor , 1995 .

[21]  M. Romantschuk,et al.  A microcosmos study on the effects of cd-containing wood ash on the coniferous humus fungal community and the cd bioavailability , 2001 .

[22]  C. Amrhein,et al.  Environmental biochemistry of chromium. , 1994, Reviews of environmental contamination and toxicology.

[23]  T. K. Misra Bacterial resistances to inorganic mercury salts and organomercurials. , 1992, Plasmid.

[24]  Comparison of the total mercury content in sediment samples with a mercury sensor bacteria test and Vibrio Fischeri toxicity test , 2000 .

[25]  M. Mergeay,et al.  Alcaligenes eutrophus CH34 is a facultative chemolithotroph with plasmid-bound resistance to heavy metals , 1985, Journal of bacteriology.

[26]  Dietrich H. Nies,et al.  Alcaligenes eutrophus as a Bacterial Chromate Sensor , 1998, Applied and Environmental Microbiology.

[27]  M Mergeay,et al.  A microbial biosensor to predict bioavailable nickel in soil and its transfer to plants. , 2001, Environmental pollution.

[28]  R. Burlage,et al.  Bioluminescent sensors for detection of bioavailable Hg(II) in the environment , 1993, Applied and environmental microbiology.

[29]  T. Kairesalo,et al.  Mobility and bioavailability of lead in contaminated boreal forest soil , 2000 .

[30]  G. Paton,et al.  Assessment of bioavailability of heavy metals using lux modified constructs of Pseudomonas fluorescens , 1995 .

[31]  S. J. Beard,et al.  Zinc(II) tolerance in Escherichia coli K‐12: evidence that the zntA gene (o732) encodes a cation transport ATPase , 1997, Molecular microbiology.

[32]  Ralph R. Turner,et al.  Application of a mer-lux biosensor for estimating bioavailable mercury in soil , 2000 .

[33]  G. Castillo,et al.  Ecotoxicity assessment of metals and wastewater using multitrophic assays , 2000 .

[34]  V. Golimbet,et al.  Viability and genetic stability of the bacterium Escherichia coli HB101 with the recombinant plasmid during preservation by various methods. , 1991, Cryobiology.

[35]  M. R. Binet,et al.  Cd(II), Pb(II) and Zn(II) ions regulate expression of the metal‐transporting P‐type ATPase ZntA in Escherichia coli , 2000, FEBS letters.

[36]  P. Vanhala,et al.  Soil respiration, ATP content, and Photobacterium toxicity test as indicators of metal pollution in soil , 1994 .

[37]  Herbert Muntau,et al.  Certification of trace metal extractable contents in a sediment reference material (CRM 601) following a three-step sequential extraction procedure , 1997 .

[38]  N. Brown,et al.  ZntR is a Zn(II)‐responsive MerR‐like transcriptional regulator of zntA in Escherichia coli , 1999, Molecular microbiology.