Journal or Publishing Institution: Environmental Biosafety Research
Date of Publication: 07/01/2003
Study: http://www.ncbi.nlm.nih.gov/pubmed/15612415
Author(s): Alpert, C.A., Mater, D.D., Muller, M.C., Ouriet, M.F., Duval-Iflah, Y., and Corthier, G.
Article Type: Peer Reviewed Study
Abstract:
Since genetically modified (GM) lactic acid bacteria (LAB) might be released in open environments for future nutritional and medical applications, the purpose of this study was to determine an upper limit for the horizontal gene transfer (HGT) in the digestive tract (DT) from Lactococcus lactis carrying heterologous genes (lux genes encoding a bacterial luciferase) to Enterococcus faecalis. Two enterococcal wide host-range conjugative model systems were used: (i) a system composed of a mobilizable plasmid containing the heterologous lux genes and a native conjugative helper plasmid; and (ii) a Tn916-lux transposon. Both systems were tested under the most transfer-prone conditions, i.e. germfree mice mono-associated with the recipient E. faecalis. No transfer was observed with the transposon system. Transfers of the mobilizable plasmid carrying heterologous genes were below 10(2) transconjugants per g of faeces for a single donor dose and reached between 10(3) and 10(4) transconjugants per g of faeces when continuous inoculation of the donor strain was used. Once established in mice, transconjugants persisted at low levels in the mouse DT.
Keywords: horizontal gene transfer, lateral gene transfer, Lactococcus lactis, Enterococcus faecalis, conjugative transposon, conjugative and mobilizable plasmids, digestive tract, luciferase, genetically modified bacteria, gnotobiotic mice, rodents, gene flow
Citation:
Alpert, C.A., Mater, D.D., Muller, M.C., Ouriet, M.F., Duval-Iflah, Y., and Corthier, G., 2003. Worst-case scenarios for horizontal gene transfer from Lactococcus lactis carrying heterologous genes to Enterococcus faecalis in the digestive tract of gnotobiotic mice. Environmental Biosafety Research, 2(3), pp. 173-80.
Category:
- Health effects
Record ID: 38