Growth of L. salivarius LS201(pLS210), L. plantarum NCIMB8826(pLS210), and L. fermentum DSM20055(pLS210) and the concomitant detection of bioluminescence (A, B). (A) Lane 1, L. salivarius LS201(pLS210); lane 2, L. plantarum NCIMB8826(pLS210); lane 3, L. fermentum DSM20055(pLS210); 0 h, time of inoculation. (B) Closed symbols, growth of Lactobacillus; open symbols, strength of bioluminescence; circle, L. salivarius LS201(pLS210); square, L. plantarum NCIMB8826(pLS210); triangle, L. fermentum DSM20055(pLS210). The error bars indicate the standard deviations of the results from three individual experiments. (C) Expression of gfp+ in L. salivarius LS201 by pLS214. Fluorescence was detected by fluorescence microscopy as described in Materials and Methods.