Administration of the ProbioticEscherichia coliStrain A0 34/86 Resulted in a Stable Colonization of the Human Intestine During the First Year of Life

Colinfant New Born (CNB) is an orally administered probiotic preparation containing theEscherichia colistrain A0 34/86, which is specially marketed for use in newborns and infants. Although the impact of different probiotics on the composition of the human gut microbiota has been previously described, the effects ofE. coliprobiotic consumption during infancy on the development of intestinal microbiota are not known. The effect of oral administration of CNB on theEnterobacteriaceaepopulation was mapped using 16S rRNA gene sequencing in DNA samples isolated from the stools of one infant collected at 177 different time points during the first year of life.E. colistrains turnover was analyzed based on the detection of 26 genetic determinants, phylogroups, and pulsed-field gel electrophoresis (PFGE) analysis. Administration of CNB during the second and third month of life introduced theEscherichiagenus to the infant's intestinal tract, andEscherichiabecame dominant among theEnterobacteriaceaefamily (p < 0.01). Genetic determinants, typical for probioticE. coliA0 34/86 strain, were detected on the first day after application of CNB and persisted all year. In addition, nine transientE. colistrains were identified; these strains harbored different genetic determinants and showed different PFGE profiles. Transient strains were detected from 2 to 24 days in the stool samples. The firstEscherichiacolonizer originated from the application of the CNB probiotic preparation. ProbioticE. coliA0 34/86 successfully colonized the intestinal tract of an infant and became resident during the first year of life.