Survival of Lactobacillus helveticus strain CP53 in the human gastrointestinal tract

A strain of Lactobacillus helveticus carrying the cryptic plasmid pCP53 tva s used for a detailed analysis of the survival and persistence of this orga nism in the faeces of volunteers administered oral doses of the strain. The CP53 strain had high affinity for Caco-2 cells, but displayed low bile aci d resistance in vitro. Rifampicin-resistant colonies could be reisolated fr om the faeces of four of seven subjects fed with the rifampicin-resistant C P53 derivative strain. Moreover, the recovery of cells, as estimated by pla smid analysis, was higher than that estimated by measuring the number of ri fampicin-resistant cells. From these results, vue conclude that the CP53 st rain can survive passage through the gastrointestinal tract.