INVESTIGADORES
MENDOZA Lucia Margarita
congresos y reuniones científicas
Título:
Biofilm-forming vaginal lactobacilli inhibit Eschericia coli isolated from women with urinary infections
Autor/es:
M. CECILIA LECCESE TERRAF; M. SILVINA JUAREZ TOMAS; LUCÍA M. MENDOZA; CLARA SILVA; M. ELENA FATIMA NADER-MACÍAS
Lugar:
Córdoba
Reunión:
Jornada; 3ra Reunión Internacional de Ciencias Farmacéuticas (RICIFA 2014); 2014
Resumen:
Lactobacilli are the dominant microorganisms of
the healthy human vagina and participate in the maintenance of the ecological
balance of the urogenital tract. They can
inhibit the growth of urogenital
pathogens by different mechanisms. The intravaginal administration of
beneficial lactobacilli in pharmaceutical products has been proposed to restore
the vaginal microbiome. The biofilm formation of lactobacilli is a beneficial
characteristic to favor their mucosal colonization and/or permanence. In this
study, the virulence factors of clinical Escherichia coli isolates and the inhibitory
ability of biofilm-forming vaginal lactobacilli against this uropathogen
were evaluated. The resistance of E. coli 36 and 36a (isolated from a
patient with pyelonephritis) and E. coli
275 (isolated from a patient with recurrent cystitis) to different antibiotics (determined
by disc diffusion method, according to Clinical and Laboratory Clinical
Institute recommendations) and the presence of virulence genes (by multiplex
PCR) were assayed. Antimicrobial activity of vaginal Lactobacillus rhamnosus CRL1332, Lactobacillus reuteri CRL1324 and Lactobacillus gasseri CRL 1263 was assayed
using the agar plate diffusion technique. Lactobacillus
supernatant aliquots were assayed, either untreated, neutralized with NaOH or
neutralized and treated with catalase. E. coli 36 and 36a were susceptible to all
the antibiotics tested, while E. coli
275 resulted an ESBL (extended-spectrum-beta-lactamase)-producing strain. In E. coli 36 and 36a, fimH, papAH (adhesins), fyuA (siderophore), traT (serum resistance) and kpsMTII
(capsule) genes were detected. In E. coli
275, fimH, fyuA, traT and agn43 (biofilm formation) genes were evidenced.
L.
reuteri CRL1324 and L. rhamnosus CRL1332 were able to
inhibit the growth of the three E. coli strains.
The inhibitory activity against E. coli
disappeared after the supernatant neutralization, indicating that organic acids
are responsible of the antagonism. The Lactobacillus strains evaluated are promising probiotic
candidates to prevent or treat urinary infections caused by E. coli.