caa a22 4500 397552912 CHVBK 20180308164755.0 cr unu---uuuuu 161202e199610 xx s 000 0 eng 10.1111/j.1574-6941.1996.tb00341.x doi (NATIONALLICENCE)oxford-10.1111/j.1574-6941.1996.tb00341.x Recombinant plasmid DNA mobilization by activated sludge strains grown in fixed-bed or sequenced-batch reactors [Elektronische Daten] [N. Frank, A.M. Simao-Beaunoir, M.A. Dollard, P. Bauda] The possibilities of mobilizing recombinant DNA (rDNA) by strains from activated sludge have been studied. A mixture of ten bacterial strains isolated from activated sludge was grown on a support in a continuously fed fixed-bed reactor or in suspension in a sequenced-batch reactor with biomass recycling. After reaching steady state, the bacteria in both types of reactors were used as the recipient population for evaluating the dissemination of the non-conjugative and non-mobilizable recombinant plasmid pCE328. The dissemination of this plasmid, derived from pBR328 (tra−, mob−, oriT−), was studied in comparison with that of pCE325 (pBR325 derivative tra−, mob−, oriT+), and that of the natural broad host range conjugative plasmid R388 (IncW). Initially the mobilization properties of pBR type recombinant plasmids between two strains of Escherichia coli were determined in the fixed-bed reactor. Only the mobilization of the recombinant plasmid bearing a transfer origin (pCE325) was observed. The survival of E. coli strains bearing either the non-transferable plasmid pCE328 or the conjugative plasmid R388 and added to the activated sludge reactors was measured in the effluent of both types of reactors. In the fixed-bed reactor effluent, the donor populations remained stable after three days of operation and reached 103 to 105 colony forming units (cfu) ml−1, whereas they decreased in the sequenced-batch reactors: donors bearing the pCE328 plasmid decreased by 2 log units in 20 days, whereas those bearing the R388 plasmid decreased by less than 1 log unit. Mobilization of the pCE328 plasmid could not be detected in any case. Transfer of the conjugative plasmid R388, used as a positive propagation control, was detected in strains arising from activated sludge in both types of reactors. Nevertheless, establishment of transconjugants was observed only in the fixed biomass at the rate of 10−7 transconjugants per recipient. © 1996 Federation of European Microbiological Societies. Published by Elsevier Science B.V. Genetically engineered microorganism nationallicence Mobilization nationallicence Biofilm nationallicence Sequenced-batch reactor nationallicence Frank N. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut Simao-Beaunoir A.M. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut Dollard M.A. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut Bauda P. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut FEMS Microbiology Ecology Blackwell Publishing Ltd 21/2(1996-10), 139-148 21:2<139 1996 21 femsec https://doi.org/10.1111/j.1574-6941.1996.tb00341.x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1111/j.1574-6941.1996.tb00341.x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Frank N. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut NATIONALLICENCE 700 1- Simao-Beaunoir A.M. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut NATIONALLICENCE 700 1- Dollard M.A. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut NATIONALLICENCE 700 1- Bauda P. Microbiology Laboratory, Centre des Sciences de l'Environnement, 1 rue des Recollets, 57040 Metz Cedex 1, France aut NATIONALLICENCE 773 0- FEMS Microbiology Ecology Blackwell Publishing Ltd 21/2(1996-10), 139-148 21:2<139 1996 21 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