caa a22 4500 397552327 CHVBK 20180308164753.0 cr unu---uuuuu 161202e199602 xx s 000 0 eng 10.1111/j.1574-6941.1996.tb00206.x doi (NATIONALLICENCE)oxford-10.1111/j.1574-6941.1996.tb00206.x Transfer of the plasmid RP1 in vivo in germ free mice and in vitro in gut extracts and laboratory media [Elektronische Daten] [Camilla U. Rang, Ruth M. Kennan, Tore Midtvedt, Lin Chao, Patricia L. Conway] The frequency of conjugal transfer of the plasmid RP1 from two different Escherichia coli donor strains (HB101 and X7, RifR) to the same E. coli recipient strain (X7, NalR) was measured in vivo (germ free mice) and in vitro (intestinal extracts, caecal contents and laboratory liquid and agar media). The transfer frequencies of the plasmid from X7, RifR and HB101 in vivo were not significantly different from those obtained when using intestinal extracts or caecal contents. In contrast, compared to in vivo, a significant difference in frequency of transfer was obtained from one of the donors, X7, RifR when using laboratory liquid media (P < 0.05) and a significant difference in frequency was noted for donor HB101 when using laboratory agar (P < 0.01). When comparing the ratio of transfer frequency between the two different donors, the plasmid consistently transferred at a higher frequency in vivo and in in vitro caecal contents from X7, RifR than from HB101 (P < 0.05). The same pattern was observed when using in vitro intestinal extracts (P > 0.05). In contrast, when laboratory agar was used, the opposite occurred and the transfer was greater from HB101 than from X7, RifR (P < 0.05). The transfer frequency in laboratory liquid media was highly variable from donor X7, RifR and no significant difference (P > 0.05) could be seen between the two donors. We conclude that the intestinal extracts and caecal contents better reflect the natural environment than any of the laboratory media tested for the parameter investigated. Furthermore, it is shown that transfer using laboratory agar did not reflect in vivo conditions. The data supports the concept of using sub-samples of an ecosystem as a microcosm for modelling the ecosystem. © 1996 Federation of European Microbiological Societies. All rights reserved Germ free mouse nationallicence Conjugal gene transfer nationallicence Intestinal tract nationallicence Gut microcosms nationallicence Rang Camilla U. Department of General and Marine Microbiology, Göteborg University, Göteborg, Sweden aut Kennan Ruth M. Department of General and Marine Microbiology, Göteborg University, Göteborg, Sweden aut Midtvedt Tore Department of Medical Microbial Ecology, Karolinska Institute, Stockholm, Sweden aut Chao Lin Department of Zoology, University of Maryland, Maryland, USA aut Conway Patricia L. School of Microbiology and Immunology, University of New South Wales, Sydney NSW 2052, Australia aut FEMS Microbiology Ecology Blackwell Publishing Ltd 19/2(1996-02), 133-140 19:2<133 1996 19 femsec https://doi.org/10.1111/j.1574-6941.1996.tb00206.x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1111/j.1574-6941.1996.tb00206.x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rang Camilla U. Department of General and Marine Microbiology, Göteborg University, Göteborg, Sweden aut NATIONALLICENCE 700 1- Kennan Ruth M. Department of General and Marine Microbiology, Göteborg University, Göteborg, Sweden aut NATIONALLICENCE 700 1- Midtvedt Tore Department of Medical Microbial Ecology, Karolinska Institute, Stockholm, Sweden aut NATIONALLICENCE 700 1- Chao Lin Department of Zoology, University of Maryland, Maryland, USA aut NATIONALLICENCE 700 1- Conway Patricia L. School of Microbiology and Immunology, University of New South Wales, Sydney NSW 2052, Australia aut NATIONALLICENCE 773 0- FEMS Microbiology Ecology Blackwell Publishing Ltd 19/2(1996-02), 133-140 19:2<133 1996 19 femsec Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford