| The immunostimulating effects of fermented dairy products are attributed to not onlythese bioactive compounds, but also to the probiotic properties of bacteria including theirability to adhere to and colonize the intestinal tract. However, until now there has been noeffective method to measure the adhesion of probiotics to the intestinal tract. Furthermore, there are not any papers that describe the relationship between intestinaladhesion and immunomodulation because it is very difficult to determine the ability of cellsto attach to intestinal epithelium in vivo. The research here was to develop a method for the transformation of lactic acidbacteria with lux genes to produce strains with a luminescent phenotype . At the same time,the physiological characteristics of these strains were investigated. These strains will beinvaluable for future research to elucidate the behaviour of probiotic bacteria both in vitroand, more importantly, in vivo. The results are summarized below: 1. The plasmid pMG36e contains a replication origin, which also could do insertion oflux genes into the vector and got the recombinant plasmid pMG36e-luxAB andpMG36e-luxCDABE. The recombinant plasmid pMG36e-luxCDABE and plasmidpMG36e-luxAB could be successfully transformed into Lactococcus lactis cell byelectroperation, and common Lactococcus lactis has been changed into bioluminescent onewith lux genes. So the p32 also can initiate replication of lux genes in gram-positivebacteria. The transformation of lux genes into L.lactis did not influence its biologicalcharacteristics of L.lactis significantly, which means that it is possible to utilize thebiological characteristics of the luminescent L.lactis transformed with lux genes to deducethe biological characteristics of L.lactis in vivo. 2. When grown on surface of agar plate added erythromycin, the luminescent L.lactistransformed with lux genes started to emit light after 40h, with a maximum light intensityoccurring at around 46h. Light emission ceased after 114h. In broth added erythromycin,the strongest light was seen at 5h, and vanished after 9h. When grown in broth added erythromycin, the strongest light of the luminescentL.lactis transformed with lux genes was seen at 5h and peak RLU of the luminescentABSTRACT VL.lactis transformed with luxAB genes was about 959759, and peak RLU of the luminescentL.lactis transformed with luxCDABE genes was about 556779; It is reported the peak RULof Listeria(Gram negative bactria) is at 2h and higher(106) than the peak RLU of theluminescent L.lactis transformed with lux genes. 3. When grown on surface of agar plate or in broth, the luminescent L.lactistransformed with luxAB genes showed significantly stronger light than the luminescentL.lactis transformed with luxCDABE genes, and when grown on surface of agar plate or inbroth of GM17, the luminescent L.lactis transformed with lux genes showed significantlystronger light than the luminescent L.lactis transformed with lux genes when grown onsurface of agar plate or in broth of M17, and when grown on surface of agar plate or inbroth supplemented with erythromycin, the luminescent L.lactis transformed with lux genesshowed significantly stronger light than the luminescent L.lactis transformed with lux geneswhen grown on surface of agar plate or in broth without erythromycin. 4. When incubated in a broth without erythromycin, the RLU of the luminescentL.lactis containing luxCDABE genes become smaller and smaller, and lose ability to set outlight after 3-5 times of transferring to a fresh medium; In contrast, when incubated in abroth without erythromycin, the luminescent L.lactis containing luxAB genes was able togive light after 10 times of transferring to a fresh medium. 5. When the luminescent L.lactis transformed with luxAB were incubated in 5h(atmaximal RLU) with GM17e, and even though the pH of medium was reduced to 2.54 bya...
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