Effects of tetracycline on the soil microflora: function, diversity, resistance
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Tetracycline is a widely used antibiotic in animal production. Significant amounts of the substance reach the soil via feces, urine and manure application. As tetracycline is a persistent compound with antibacterial activity, its presence in soil may have undesired direct and indirect effects. These have been investigated so far focusing on effects on selected microbial functions.
The aim of the present study was to obtain comprehensive information on potential effects of tetracycline on the soil microflora under environmentally relevant conditions. The investigations included function and structure of the microbial biocoenosis and the distribution of resistance genes.
Pig manure rich in tetracycline resistance genes was applied to a sandy soil. This soil as well as an unamended soil were additionally treated with several concentrations of tetracycline. The spiked soils were incubated in outdoor lysimeters for several months. Substrate induced respiration, PLFAs, ten selected resistance genes, and the concentrations of tetracycline were determined.
The test concentrations, though far exceeding environmental relevance, caused only small effects. An establishment of resistance could not be detected. Applied resistance genes were not detectable at the end of the study even in the presence of added tetracycline.
Due to the high sorption capacity of the antibiotic, environmentally relevant concentrations of tetracycline do not seem to cause undesired effects on the soil microflora.
KeywordsAntibiotics microbial function microbial structure soil tetracycline resistance
- Commission of the EEC (1992) : Directive 92/18/EEC. Off J EEC L 97, 1-12Google Scholar
- Cooper AD, Stubbings GWF, Kelly M, Tarbin JA, Farrington WHH, Shearer G (1998): Improved method for the on-line metal chelate affinity chromatogra-phy-high-performance liquid chromatographic determination of tetracycline antibiotics in animal products. Journal of Chromatography A 812, 321–326CrossRefGoogle Scholar
- Daane LL, Molina JA, Berry EC, Sadowsky MJ (1996): Influence of earthworm activity on gene transfer fromPseudomonas fluorescence to indigenous soil bacteria. Appl Environ Microbiol 62, 515–521Google Scholar
- EN ISO 10712 (1995): Water quality —Pseudomonas putida growth inhibition test (Pseudomonas cell multiplication inhibition test) (ISO 10712:1995)Google Scholar
- Franklin TJ, Snow GA (1981): Biochemistry of antimicrobial action, 3nd edition. Chapman and Hall: London, 217 pp.Google Scholar
- Fruend H-C, Schoesser A, Westendorp H (2000): Effects of tetracycline on the soil microflora determined with microtiter plates and respiration measurement. Mitteilungen Dtsch Bodenkundl Gesellsch 93, 244–247Google Scholar
- Gotz A, Smalla K (1997): Manure enhances plasmid mobilization and survival inPseudomonas putida introduced into the field soil. Appl Environ Microbiol 63, 1980–1986Google Scholar
- Guillaume G, Verbrugge D, Chasseur-Libotte M-L, Moens W, Collard J-M (2000): PCR typing of tetracycline resistance determinants (Tet A-E) inSalmonella enterica serotype Hadar and in the microbial community of activated sludges from hospital and urban wastewater treatment facilities in Belgium. FEMS Microbiol Ecol 32, 77–85Google Scholar
- Hamscher G, Sczesny S, Abu-Qare A, Hoeper H, Nau H (2000): Stoffe mit pharmakologischer Wirkung einschließlich hormonell aktiver Substanzen in der Umwelt: Nachweis von Tetracyclinen in güllegedüngten Böden. Dtsch Tierarztl Wschr 107, 293–348Google Scholar
- Hoeper H, Kues J, Nau H, Hamscher G (2002): Eintrag und Verbleib von Tierarzneimittelwirkstoffen in Böden. Bodenschutz 4/02, 141–147Google Scholar
- Hoffmann A, Thimm T, Dröge M, Moore ERB, Munch JC, Tebbe CC (1998): Intergeneric transfer of conjugative and mobilizable plasmids harboured byEscherichia coli in the gut of the soil microarthropodFolsomia Candida (collembola). Appl Environ Microbiol 64, 2652–2659Google Scholar
- ISO/DIS 15685 (2001): Soil quality — Determination of potential nitrification — Rapid test by ammonium oxidationGoogle Scholar
- ISO/DIS 17155 (2001): Soil quality — Determination of abundance and activity of soil microflora using respiration curvesGoogle Scholar
- Lilley AK, Bailey MJ (997): The acquisition of indigenous plasmids by genetically marked Pseudomonad population colonizing the sugar beet phyto-sphere is related to local environmental conditions. Adv Appl Microbiol 63, 1577–1583Google Scholar
- Schnabel EL, Jones AL (1999): Distribution of Tetracycline resistance genes and transposons among phylloplane bacteria in Michigan apple orchards. Appl Environ Microbiol65, 4898–4907Google Scholar
- Sczesny S (2001): Analytik von Tetracyclinen in Umwelt- und Lebensmittel-proben mittels selektiver Extraktionsverfahren und sensitivem Nachweis durch HPLC gekoppelt mit mikrobiologischem Assay und Tandem-Massenspektrometrie. Dissertation. Tierärztliche Hochschule HannoverGoogle Scholar
- Smit E, Wolters A, van Elsas JD (1998): Self-transmissible mercury resistance plasmids with gene-mobilizing capacity in soil bacterial populations: Influence of wheat roots and mercury addition. Appl Environ Microbiol 64, 1210–1219Google Scholar
- Thimm T, Hoffman A, Fritz I, Tebbe CC (2001): Contribution of the earthwormLumbricus rubellus (Annelida, Oligochaeta) to the establishment of plasmids in soil bacterial communities. Microbiol Ecol 41, 341–351Google Scholar