Development of strain-specific PCR reactions for the detection of the probiotic Escherichia coli strain Nissle 1917 in fecal samples

Analysis of the Genome Structure of the Nonpathogenic Probiotic Escherichia coli Strain Nissle 1917

“…186, 2004 GENOME ANALYSIS OF ESCHERICHIA COLI STRAIN NISSLE 1917 5439 Nissle 1917 is characterized by a specific combination of traits, as it acquired a set of important determinants which enable successful survival and colonization of the human intestine. In addition, this strain does not express important UPEC virulence factors (i.e., alpha-hemolysin, P-fimbrial adhesins, serum resistance-conferring long-chain O6 LPS), and it exhibits some phenotypic features which are not typical for the two UPEC isolates included into this study: the presence of six different iron uptake systems, the temperature-independent expression of curli and cellulose (unpublished results), a FimB-independent type 1 fimbrial switch (53), the presence of two small plasmids (9), and a semirough LPS responsible for serum sensitivity (20). This specific combination of traits, which most likely represents the basis of its probiotic nature, might mirror the process of evolutionary withdrawal from the pathogenic E. coli serotype O6 lineages, indicating that horizontal gene transfer, subsequent loss of horizontally acquired genetic information, and point mutations have been involved in the evolution of strain Nissle 1917.…”

“…All of the strain Nissle 1917-specific sequences included into the PCR screening approach were detectable in two of the investigated O6:K5 isolates (strains RZ442 and RZ525), thus suggesting a common clonal origin of these strains. However, further comparison of their genome content using PCR primer pairs for amplification of the two cryptic plasmids of strain Nissle 1917, pMUT1 and pMUT2 (9), showed that both strains contained only pMUT1. In addition, the E. coli strains RZ442 and RZ525 differ phenotypically from strain Nissle 1917.…”

Safety of ProbioticEscherichia coliStrain Nissle 1917 Depends on Intestinal Microbiota and Adaptive Immunity of the Host

“…The numbers of CFU per plate were determined and expressed as log 10 CFU/g organ (limit of detection, 50 CFU). For identification of E. coli strain Nissle 1917, PCR was performed using primers specific for the pMUT1 plasmid and for the pMUT2 plasmid as described previously (8).…”

Construction of recombinant E. coli Nissle 1917 (EcN) strains for the expression and secretion of defensins

“…This strain was originally isolated by Alfred Nissle in 1917 from a soldier who was not affected, in contrast to his comrades, by a severe outbreak of diarrhea (Blum-Oehler et al 2003). …”

“…coli Nissle 1917 has been thoroughly analyzed by means of microbiological, biochemical and molecular genetic methods (Blum-Oehler et al 2003, Blum et al 1995, Grozdanov et al 2004, Grozdanov et al 2002. The strain does not exhibit any virulence factors, but has gene clusters located on genomic islands (GEIs) responsible for the synthesis of several so-called `fitness factors´, which contribute to the strain's probiotic nature.…”