Identification and characterization of OmpT ‐like proteases in uropathogenic Escherichia coli clinical isolates

Here, we investigated omptin protease ‐mediated antimicrobial resistance among uropathogenicEscherichia coli clinical isolates. We found that clinical isolates with the highest omptin protease activity encode multiple omptin proteases, showing different substrate specificities. Our data suggest that the presence of multiple omptin family proteases in a single clinical isolate may provide a fitness advantage by expanding the range of natural antimicrobial peptides cleaved during urogenital tract colonization. AbstractBacterial colonization of the urogenital tract is limited by innate defenses, including the production of antimicrobial peptides (AMPs). UropathogenicEscherichia coli (UPEC) resist AMP ‐killing to cause a range of urinary tract infections (UTIs) including asymptomatic bacteriuria, cystitis, pyelonephritis, and sepsis. UPEC strains have high genomic diversity and encode numerous virulence factors that differentiate them from non‐UTI‐causing strains, includingompT. As OmpT homologs cleave and inactivate AMPs, we hypothesized that UPEC strains from patients with symptomatic UTIs have high OmpT protease activity. Therefore, we measured OmpT activity in 58 clinicalE.  coli isolates. While heterogeneous OmpT activities were observed, OmpT activity was significantly greater in UPEC strains isolated from patients with symptomatic infections. Unexpectedly, UPEC strains exhibiting the greatest protease activities harbored an additionalompT‐like gene calledarlC (o...
Source: MicrobiologyOpen - Category: Microbiology Authors: Tags: SPECIAL ISSUE: ANTIMICROBIAL RESISTANCE Source Type: research