Interaction between atypical microorganisms andE. coliin catheter-associated urinary tract biofilms

Abstract

Most biofilms involved in catheter-associated urinary tract infections (CAUTIs) are polymicrobial, with disease causing (eg Escherichia coli) and atypical microorganisms (eg Delftia tsuruhatensis) frequently inhabiting the same catheter. Nevertheless, there is a lack of knowledge about the role of atypical microorganisms. Here, single and dual-species biofilms consisting of E. coli and atypical bacteria (D. tsuruhatensis and Achromobacter xylosoxidans), were evaluated. All species were good biofilm producers (Log 5.84-7.25 CFU cm(-2) at 192 h) in artificial urine. The ability of atypical species to form a biofilm appeared to be hampered by the presence of E. coli. Additionally, when E. coli was added to a pre-formed biofilm of the atypical species, it seemed to take advantage of the first colonizers to accelerate adhesion, even when added at lower concentrations. The results suggest a greater ability of E. coli to form biofilms in conditions mimicking the CAUTIs, whatever the pre-existing microbiota and the inoculum concentration.

Removal of Listeria monocytogenes dual-species biofilms using combined enzyme-benzalkonium chloride treatments

“…monocytogenes as previously reported (Azevedo et al 2014). However, AVC values of both species were equilibrated at 36, 48 and 72 hours (Fig.…”

An in vitro model of catheter-associated urinary tract infections to investigate the role of uncommon bacteria on the Escherichia coli microbial consortium

“…The role of uncommon bacteria is underestimated probably due to the absence of commercial media and kits to detect these bacteria in hospitals. But, as reported in previous studies [15,17], E. coli and uncommon bacteria are good biofilm producers on abiotic surfaces (e.g. silicone, polystyrene), and when in co-culture they are able to form a stable microbial consortia, where both bacteria coexist, even when inoculated at different proportions.…”

“…The growth rate for each bacterium was determined in AUM (without yeast extract and peptone) in a batch culture as described in a study performed by Azevedo et al [17].…”

“…In addition, the flow rate was adjusted to mimic a natural urine flow (see calculations in Supplementary Method 1); it should be noticed that within the human body the catheter will be subjected to an intermittent flow, with periods from absent to high flow rates. As previous experiments were performed under static conditions [15,17], the dynamic system used in present study allowed to simulate the periods of high urine flow rate. Also, this system only allows a correct simulation of an intraluminal colonization, as flow is restricted to the catheter lumen.…”

Synergistic cranberry juice combinations with natural‐borne antimicrobials for the eradication of uropathogenic Escherichia coli biofilm within a short time

“…UPEC biofilms were formed on silicon coupons as described previously, (Azevedo et al . ) with some modifications. Briefly, silicon coupons measuring 1·5 × 2 cm 2 were immersed for 30 min in 90% (v/v) ethanol (Petaling Jaya, Selangor, Malaysia), rinsed with distilled water (DW) and air‐dried.…”