Study of resistance mechanisms and capacity for biofilm production of entrococci isolated from animals in comparison with strains from human infectons

The present study investigated the possible correlation between carriage of the virulence genes esp and fsrb, production of hemolysin and gelatinase and biofilm formation in human vs. animal enterococcal isolates. A collection of 219 enterococcal isolates recovered from clinical and fecal surveillance samples of hospitalized patients and 132 isolates from animal feces were studied. Isolates were tested for hemolysin and gelatinase phenotypically and for quantitative biofilm production by a microtitre method. Genes esp and fsrb were detected by PCR. Human Enterococcus faecium and Enterococcus faecalis isolates from both surveillance and clinical samples produced biofilm significantly more often than animal isolates (P < 0.0001 for both species). The quantity of biofilm did not differ significantly between human and animal isolates, while was significantly higher in esp-positive compared with esp-negative human E. faecium isolates (P < 0.0001). The frequency of esp gene carriage was significantly higher in human compared with animal E. faecium and E. faecalis isolates (P < 0.0001). The gene fsrb was detected significantly more often in animal than human E. faecium isolates (P 0.004). Hemolysin production was significantly more common in human clinical compared with animal E. faecalis isolates (P < 0.0001). Similar proportions of animal and human E. faecalis produced gelatinase, which was significantly correlated with the presence of fsrb gene (P < 0.0001) in both human clinical and animal E. faecalis isolates. The hemolysin trait did not exhibit any correlation with the presence of esp and fsrb genes, but appeared to be linked with enhanced quantity of biofilm production in both human clinical and animal E. faecalis isolates. Production of gelatinase was associated with the proportion and the degree of biofilm production mainly in animal E. faecalis isolates.Η παρούσα μελέτη διερεύνησε την πιθανή συσχέτιση μεταξύ της παρουσίας των γονιδίων esp και fsrb, της παραγωγής αιμολυσίνης, ζελατινάσης και του σχηματισμού βιομεμβράνης σε στελέχη εντεροκόκκων από ανθρώπους σε σύγκριση με στελέχη από ζώα. Μελετήθηκαν 219 στελέχη εντερόκοκκων που ανακτήθηκαν από κλινικά δείγματα και από κόπρανα ασθενών και 132 στελέχη από κόπρανα ζώων. Τα στελέχη εξετάστηκαν για την παραγωγή αιμολυσίνης και ζελατινάσης με φαινοτυπικές μεθόδους και για την παραγωγή βιομεμβράνης με τη μέθοδο μικροτιτλοποίησης πλακών. Τα γονίδια esp και fsrb ανιχνεύθηκαν με PCR. Τα ανθρώπινα στελέχη Enterococcus faecium και Enterococcus faecalis τόσο από κόπρανα όσο και από κλινικά δείγματα σχημάτισαν βιομεμβράνες πολύ πιο συχνά από ό, τι τα ζωϊκά στελέχη (P < 0.0001 και για τα δύο είδη). Η ποσότητα της βιομεμβράνης δεν διέφερε σημαντικά μεταξύ των ανθρώπινων και των στελεχών από ζώα, ενώ ήταν σημαντικά υψηλότερη στα esp-θετικά σε σύγκριση με τα esp-αρνητικά ανθρώπινα στελέχη Ε. faecium (P < 0.0001). Η συχνότητα του γονιδίου esp ήταν σημαντικά υψηλότερη στα ανθρώπινα σε σύγκριση με τα ζωϊκά στελέχη Ε. faecium και E. faecalis (P < 0.0001). Το γονίδιο fsrb εντοπίστηκε σημαντικά πιο συχνά στα ζωϊκά στελέχη Ε. faecium από τα ανθρώπινα (P 0.004). H παραγωγή της αιμολυσίνης ήταν σημαντικά συχνότερη στα ανθρώπινα κλινικά E. faecalis σε σύγκριση με τα στελέχη ζώων (P < 0.0001). Παρόμοια ποσοστά των ανθρώπινων και των ζωϊκών E. faecalis παράγανε ζελατινάση, η οποία συσχετίστηκε σημαντικά με την παρουσία του γονιδίου fsrb (P <0.0001) τόσο στα κλινικά όσο και στα ζωικά στελέχη Ε. faecalis. H ιδιότητα της αιμολυσίνης δεν παρουσίασε καμία συσχέτιση με την παρουσία των γονιδίων esp και fsrb αλλά φάνηκε να συνδέεται με αυξημένη ποσότητα της παραγόμενης βιομεμβράνης τόσο των ανθρώπινων κλινικών όσο και των ζωϊκών στελεχών E. faecalis. Η παραγωγή ζελατινάσης συνδέθηκε με το ποσοστό και τον βαθμό της παραγωγής βιομεμβράνης κυρίως σε στελέχη E. faecalis από κόπρανα ζώων

Differences in biofilm formation and virulence factors between clinical and fecal enterococcal isolates of human and animal origin

The present study investigated the possible correlation between carriage of the virulence genes esp and fsrb, production of hemolysin and gelatinase and biofilm formation in human vs. animal enterococcal isolates. A collection of 219 enterococcal isolates recovered from clinical and fecal surveillance samples of hospitalized patients and 132 isolates from animal feces were studied. Isolates were tested for hemolysin and gelatinase phenotypically and for quantitative biofilm production by a microtitre method. Genes esp and fsrb were detected by PCR. Human Enterococcus faecium and Enterococcus faecalis isolates from both surveillance and clinical samples produced biofilm significantly more often than animal isolates (P &lt; 0.0001 for both species). The quantity of biofilm did not differ significantly between human and animal isolates, while was significantly higher in esp-positive compared with esp-negative human E. faecium isolates (P &lt; 0.0001). The frequency of esp gene carriage was significantly higher in human compared with animal E. faecium and E. faecalis isolates (P &lt; 0.0001). The gene fsrb was detected significantly more often in animal than human E. faecium isolates (P 0.004). Hemolysin production was significantly more common in human clinical compared with animal E. faecalis isolates (P &lt; 0.0001). Similar proportions of animal and human E. faecalis produced gelatinase, which was significantly correlated with the presence of fsrb gene (P &lt; 0.0001) in both human clinical and animal E. faecalis isolates. The hemolysin trait did not exhibit any correlation with the presence of esp and fsrb genes, but appeared to be linked with enhanced quantity of biofilm production in both human clinical and animal E. faecalis isolates. Production of gelatinase was associated with the proportion and the degree of biofilm production mainly in animal E. faecalis isolates. © 2012 Elsevier Ltd

Differences in biofilm formation and virulence factors between clinical and fecal enterococcal isolates of human and animal origin

The present study investigated the possible correlation between carriage of the virulence genes esp and fsrb, production of hemolysin and gelatinase and biofilm formation in human vs. animal enterococcal isolates. A collection of 219 enterococcal isolates recovered from clinical and fecal surveillance samples of hospitalized patients and 132 isolates from animal feces were studied. Isolates were tested for hemolysin and gelatinase phenotypically and for quantitative biofilm production by a microtitre method. Genes esp and fsrb were detected by PCR. Human Enterococcus faecium and Enterococcus faecalis isolates from both surveillance and clinical samples produced biofilm significantly more often than animal isolates (P < 0.0001 for both species). The quantity of biofilm did not differ significantly between human and animal isolates, while was significantly higher in esp-positive compared with esp-negative human E. faecium isolates (P < 0.0001). The frequency of esp gene carriage was significantly higher in human compared with animal E. faecium and E. faecalis isolates (P < 0.0001). The gene fsrb was detected significantly more often in animal than human E. faecium isolates (P 0.004). Hemolysin production was significantly more common in human clinical compared with animal E. faecalis isolates (P < 0.0001). Similar proportions of animal and human E. faecalis produced gelatinase, which was significantly correlated with the presence of fsrb gene (P < 0.0001) in both human clinical and animal E. faecalis isolates. The hemolysin trait did not exhibit any correlation with the presence of esp and fsrb genes, but appeared to be linked with enhanced quantity of biofilm production in both human clinical and animal E. faecalis isolates. Production of gelatinase was associated with the proportion and the degree of biofilm production mainly in animal E. faecalis isolates. (c) 2012 Elsevier Ltd. All rights reserved

Effects of single- and multi-strain probiotics on biofilm formation and in vitro adhesion to bladder cells by urinary tract pathogens

Inhibition of biofilm seems to be a major mechanism of urinary tract pathogen exclusion, related to, and possibly dependent upon, the probiotic ability to reduce environmental pH. Exclusion via competition of binding sites is a possible in vivo mechanism for these probiotics. If an additive or synergistic effect exists between strains within a mixture, it does not manifest itself in a greater effect through these two inhibitory mechanisms