Biofilm Formation by Uropathogenic Escherichia coli Is Favored under Oxygen
Conditions That Mimic the Bladder Environment.
Authors Eberly AR, Floyd KA, Beebout CJ, Colling SJ, Fitzgerald MJ, Stratton CW, Schmitz
JE, Hadjifrangiskou M
Submitted By Submitted Externally on 11/13/2017
Status Published
Journal International journal of molecular sciences
Year 2017
Date Published 9/1/2017
Volume : Pages 18 : Not Specified
PubMed Reference 28973965
Abstract One of the most common urologic problems afflicting millions of people worldwide
is urinary tract infection (UTI). The severity of UTIs ranges from asymptomatic
bacteriuria to acute cystitis, and in severe cases, pyelonephritis and
urosepsis. The primary cause of UTIs is uropathogenic Escherichia coli (UPEC),
for which current antibiotic therapies often fail. UPEC forms multicellular
communities known as biofilms on urinary catheters, as well as on and within
bladder epithelial cells. Biofilm formation protects UPEC from environmental
conditions, antimicrobial therapy, and the host immune system. Previous studies
have investigated UPEC biofilm formation in aerobic conditions (21% oxygen);
however, urine oxygen tension is reduced (4-6%), and urine contains molecules
that can be used by UPEC as alternative terminal electron acceptors (ATEAs) for
respiration. This study was designed to determine whether these different
terminal electron acceptors utilized by E. coli influence biofilm formation. A
panel of 50 urine-associated E. coli isolates was tested for the ability to form
biofilm under anaerobic conditions and in the presence of ATEAs. Biofilm
production was reduced under all tested sub-atmospheric levels of oxygen, with
the notable exception of 4% oxygen, the reported concentration of oxygen within
the bladder.