Virulence Factors of Uropathogenic E. coli

Abstract

In order for a successful infection and creating a satisfactory environment inside the host, strains of uropathogenic Escherichia coli (UPEC) need some special features that are achieved by expressing particular genes, called virulence factors. Two of the most important surface virulence factors of UPEC are type 1 fimbriae and P fimbriae that are crucial for the colonization process inside the urinary tract. Expression of these virulence factors converts a commensal strain into an uropathogen. Beside these factors, outer membrane proteins also contribute to virulence being involved in the secretory machinery; an example of such type is TolC protein that transfers α-hemolysin across the outer membrane of E. coli. However, α-hemolysin along with many other toxins serves various pathogenic roles during UTIs including adhesion, colonization, cytotoxic activity, etc. Moreover, virulence factors located on bacterial surface including capsule and lipopolysaccharides may also have the contribution to UTIs providing antiphagocytosis and antibactericidal complement activity.

Cranberry Polyphenols and Prevention against Urinary Tract Infections: Relevant Considerations

“…In addition, it can be an opportunistic pathogen that uses the intracellular environment to survive and protect itself against the action of antibiotics. Several epidemiological, serological, and bacteriological studies revealed that UPEC is the pathogen most frequently associated with UTIs [40], accounting for three-quarters of all UTIs among outpatients [41,42]. These bacteria have evolved a multitude of virulence factors and strategies that facilitate bacterial growth and persistence within the adverse settings of the host urinary tract.…”

“…Other factors of virulence to highlight are the production of toxins, including α-hemolysin (HlyA), cytotoxic necrotizing factor1 (CNF1), secreted autotransporter toxin (SAT), cytolysin A, plasmid-encoded toxin (PET), vacuolating autotransporter toxin (VAT), Shigella enterotoxin-1 (ShET-1) and arginine succinyltransferase (AST) [48], and iron-chelating factors (siderophores) that enables UPEC to capture iron, both mechanisms impair host immune system and obtain nutrients and growth factors necessary for their survival. The expression of these virulence factors converts an E. coli commensal strain into an uropathogen, and, often, the inhibition of a single adhesin may cost enough to a bacterium to lose its virulence [40]. Moreover, virulence factors located on a bacterial surface, including capsule and lipopolysaccharides, may also contribute to UTIs providing antiphagocytosis and antibactericidal complement activity [40].…”

“…The expression of these virulence factors converts an E. coli commensal strain into an uropathogen, and, often, the inhibition of a single adhesin may cost enough to a bacterium to lose its virulence [40]. Moreover, virulence factors located on a bacterial surface, including capsule and lipopolysaccharides, may also contribute to UTIs providing antiphagocytosis and antibactericidal complement activity [40]. In recent years, the understanding of virulence factors and the behavior of this pathogen has increased remarkably, and may facilitate the application of more precise approaches in phenotypic, molecular diagnosis and the development of alternatives strategies to antibiotics based on antivirulence prophylaxis.…”

Cranberry Polyphenols and Prevention against Urinary Tract Infections: A Brief Review

“…Other factors of virulence to highlight are the production of toxins, including α-hemolysin (HlyA), cytotoxic necrotizing factor1 (CNF1), secreted autotransporter toxin (SAT), cytolysin A, plasmidencoded toxin (PET), vacuolating autotransporter toxin (VAT), Shigella enterotoxin-1 (ShET-1) and arginine succinyltransferase (AST) [48], and iron-chelating factors (siderophores) that enables UPEC to capture iron, both mechanisms impair host immune system and obtain nutrients and growth factors necessary for their survival. The expression of these virulence factors converts an E. coli commensal strain into an uropathogen, and often, the inhibition of a single adhesin may cost enough to a bacterium to lose its virulence [40]. Moreover, virulence factors located on a bacterial surface, including capsule and lipopolysaccharides, may also contribute to UTIs providing antiphagocytosis and antibactericidal complement activity [40].…”

Prospective antibacterial behavior of some essential aromatic oils against new Escherichia coli strain of extended-spectrum Beta-lactam

“…Clove oil because of its antimicrobial characteristics is used for pathogenic bacterial control (Packyanathan and Prakasam, 2017). Essential oils can be used as alternatives to treat many infectious diseases (Packyanathan and Prakasam, 2017;Parvez and Rahman, 2018;Hassan et al, 2018). Clove oil has antimicrobial, antifungal, antiseptic, antiviral, stimulant, and aphrodisiac properties, in addition to different basic minerals and vitamins, especially vitamin A, and may offer health advantages.…”