Monoclonal antibodies targeting the FimH adhesin protect against uropathogenic UTI.

As antimicrobial resistance increases, urinary tract infections (UTIs) are expected to pose an increased burden in morbidity and expense on the healthcare system, increasing the need for alternative antibiotic-sparing treatments. Most UTIs are caused by uropathogenic (UPEC), while causes a significant portion of non-UPEC UTIs. Both bacteria express type 1 pili tipped with the mannose-binding FimH adhesin critical for UTI pathogenesis.

Structural basis for adhesin secretion by the outer-membrane usher in type 1 pili.

Gram-negative bacteria produce chaperone-usher pathway pili, which are extracellular protein fibers tipped with an adhesive protein that binds to a receptor with stereochemical specificity to determine host and tissue tropism. The outer-membrane usher protein, together with a periplasmic chaperone, assembles thousands of pilin subunits into a highly ordered pilus fiber. The tip adhesin in complex with its cognate chaperone activates the usher to allow extrusion across the outer membrane.

Conformational ensembles in FimH impact uropathogenesis.

is an important pathogen causing difficult-to-treat urinary tract infections (UTIs). Over 1.5 million women per year suffer from recurrent UTI, reducing quality of life and causing substantial morbidity and mortality, especially in the hospital setting.

Dihydrothiazolo ring-fused 2-pyridone antimicrobial compounds treat skin and soft tissue infection.

We have developed GmPcides from a peptidomimetic dihydrothiazolo ring-fused 2-pyridone scaffold that has antimicrobial activities against a broad spectrum of Gram-positive pathogens. Here, we examine the treatment efficacy of GmPcides using skin and soft tissue infection (SSTI) and biofilm formation models by . Screening our compound library for minimal inhibitory (MIC) and minimal bactericidal (MBC) concentrations identified GmPcide PS757 as highly active against .

Discovery of Orally Bioavailable FmlH Lectin Antagonists as Treatment for Urinary Tract Infections.

FmlH, a bacterial adhesin of uropathogenic (UPEC), has been shown to provide a fitness advantage in colonizing the bladder during chronic urinary tract infections (UTIs). Previously reported -biphenyl glycosides based on βGal and βGalNAc have excellent binding affinity to FmlH and potently block binding to its natural carbohydrate receptor, but they lack oral bioavailability. In this paper, we outline studies where we have optimized compounds for improved pharmacokinetics, leading to the discovery of novel analogues with good oral bioavailability.

Dihydrothiazolo ring-fused 2-pyridone antimicrobial compounds treat skin and soft tissue infection.

We have developed GmPcides from a peptidomimetic dihydrothiazolo ring-fused 2-pyridone scaffold that have antimicrobial activities against a broad-spectrum of Gram-positive pathogens. Here we examine the treatment efficacy of GmPcides using skin and soft tissue infection (SSTI) and biofilm formation models by . Screening our compound library for minimal inhibitory (MIC) and minimal bactericidal (MBC) concentrations identified GmPcide PS757 as highly active against .

Microbial co-occurrences on catheters from long-term catheterized patients.

Catheter-associated urinary tract infections (CAUTIs), a common cause of healthcare-associated infections, are caused by a diverse array of pathogens that are increasingly becoming antibiotic resistant. We analyze the microbial occurrences in catheter and urine samples from 55 human long-term catheterized patients collected over one year. Although most of these patients were prescribed antibiotics over several collection periods, their catheter samples remain colonized by one or more bacterial species.

Vaccination with adhesin Abp2D provides protection against catheter-associated urinary tract infection.

Catheter-associated urinary tract infections (CAUTIs) contribute greatly to the burden of healthcare associated infections. is a Gram-negative bacterium with high levels of antibiotic resistance that is of increasing concern as a CAUTI pathogen. expresses fibrinogen-binding adhesins (Abp1D and Abp2D) that mediate colonization and biofilm formation on catheters, which become coated with fibrinogen upon insertion.

Structure-function correlates of fibrinogen binding by adhesins critical in catheter-associated urinary tract infections.

Multidrug-resistant  infections are an urgent clinical problem and can cause difficult-to-treat nosocomial infections. During such infections, like catheter-associated urinary tract infections (CAUTI), rely on adhesive, extracellular fibers, called chaperone-usher pathway (CUP) pili for critical binding interactions. The uropathogenic strain, UPAB1, and the pan-European subclone II isolate, ACICU, use the CUP pili Abp1 and Abp2 (previously termed Cup and Prp, respectively) in tandem to establish CAUTIs, specifically to facilitate bacterial adherence and biofilm formation on the implanted catheter.

Ring-fused 2-pyridones effective against multidrug-resistant Gram-positive pathogens and synergistic with standard-of-care antibiotics.

The alarming rise of multidrug-resistant Gram-positive bacteria has precipitated a healthcare crisis, necessitating the development of new antimicrobial therapies. Here we describe a new class of antibiotics based on a ring-fused 2-pyridone backbone, which are active against vancomycin-resistant enterococci (VRE), a serious threat as classified by the Centers for Disease Control and Prevention, and other multidrug-resistant Gram-positive bacteria. Ring-fused 2-pyridone antibiotics have bacteriostatic activity against actively dividing exponential phase enterococcal cells and bactericidal activity against nondividing stationary phase enterococcal cells.

Characterization of Host-Pathogen-Device Interactions in Pseudomonas aeruginosa Infection of Breast Implants.

Background: Pseudomonas aeruginosa accounts for 7 to 22 percent of breast implant-associated infections, which can result in reconstructive failures and explantation. Investigating host-pathogen-device interactions in mice and patient samples will improve the understanding of colonization mechanisms, for targeted treatments and clinical guidelines.

Methods: Mice with and without implants were infected with PAO1 laboratory strain or BIP2 or BIP16 clinical strains and killed at 1 day or 7 days after infection to evaluate for colonization of implants and underlying tissues by means of colony-forming unit enumeration.

Longitudinal multi-omics analyses link gut microbiome dysbiosis with recurrent urinary tract infections in women.

Recurrent urinary tract infections (rUTIs) are a major health burden worldwide, with history of infection being a significant risk factor. While the gut is a known reservoir for uropathogenic bacteria, the role of the microbiota in rUTI remains unclear. We conducted a year-long study of women with (n = 15) and without (n = 16) history of rUTI, from whom we collected urine, blood and monthly faecal samples for metagenomic and transcriptomic interrogation.

A host receptor enables type 1 pilus-mediated pathogenesis of Escherichia coli pyelonephritis.

Type 1 pili have long been considered the major virulence factor enabling colonization of the urinary bladder by uropathogenic Escherichia coli (UPEC). The molecular pathogenesis of pyelonephritis is less well characterized, due to previous limitations in preclinical modeling of kidney infection. Here, we demonstrate in a recently developed mouse model that beyond bladder infection, type 1 pili also are critical for establishment of ascending pyelonephritis.

Insights into the Microbiome of Breast Implants and Periprosthetic Tissue in Breast Implant-Associated Anaplastic Large Cell Lymphoma.

Though rare, breast implant-associated anaplastic large cell lymphoma (BIA-ALCL), a CD30+ T-cell lymphoma associated with textured breast implants, has adversely impacted our perception of the safety of breast implants. Its etiology unknown, one hypothesis suggests an initiating inflammatory stimulus, possibly infectious, triggers BIA-ALCL. We analyzed microbiota of breast, skin, implant and capsule in BIA-ALCL patients (n = 7), and controls via culturing methods, 16S rRNA microbiome sequencing, and immunohistochemistry.

Fimbriae reprogram host gene expression - Divergent effects of P and type 1 fimbriae.

Pathogens rely on a complex virulence gene repertoire to successfully attack their hosts. We were therefore surprised to find that a single fimbrial gene reconstitution can return the virulence-attenuated commensal strain Escherichia coli 83972 to virulence, defined by a disease phenotype in human hosts. E.

Deposition of Host Matrix Proteins on Breast Implant Surfaces Facilitates Staphylococcus Epidermidis Biofilm Formation: In Vitro Analysis.

Background: Staphylococcus epidermidis is a primary cause of breast implant-associated infection. S epidermidis possesses several virulence factors that enable it to bind both abiotic surfaces and host factors to form a biofilm. In addition S epidermidis colocalizes with matrix proteins coating explanted human breast implants.

The Detection of Bacteria and Matrix Proteins on Clinically Benign and Pathologic Implants.

Background: Bacterial contamination of breast implants causes infection, can lead to capsular contracture, and is implicated in breast implant-associated anaplastic large cell lymphoma. Bacteria, however, also colonize clinically benign breast implants and little is known about the biologic signals that trigger the switch from a benign to pathologic state.

Methods: Explanted smooth as well as Biocell and Siltex textured breast implants associated with clinically normal and pathologic conditions were analyzed in this observational study.

Biphenyl Gal and GalNAc FmlH Lectin Antagonists of Uropathogenic E. coli (UPEC): Optimization through Iterative Rational Drug Design.

The F9/Yde/Fml pilus, tipped with the FmlH adhesin, has been shown to provide uropathogenic Escherichia coli (UPEC) a fitness advantage in urinary tract infections (UTIs). Here, we used X-ray structure guided design to optimize our previously described ortho-biphenyl Gal and GalNAc FmlH antagonists such as compound 1 by replacing the carboxylate with a sulfonamide as in 50. Other groups which can accept H-bonds were also tolerated.

Structural basis for usher activation and intramolecular subunit transfer in P pilus biogenesis in Escherichia coli.

Chaperone-usher pathway pili are extracellular proteinaceous fibres ubiquitously found on Gram-negative bacteria, and mediate host-pathogen interactions and biofilm formation critical in pathogenesis in numerous human diseases. During pilus assembly, an outer membrane macromolecular machine called the usher catalyses pilus biogenesis from the individual subunits that are delivered as chaperone-subunit complexes in the periplasm. The usher orchestrates pilus assembly using all five functional domains: a 24-stranded transmembrane β-barrel translocation domain, a β-sandwich plug domain, an amino-terminal periplasmic domain and two carboxy-terminal periplasmic domains (CTD1 and CTD2).

Structure-Function Analysis of the Curli Accessory Protein CsgE Defines Surfaces Essential for Coordinating Amyloid Fiber Formation.

Curli amyloid fibers are produced as part of the extracellular biofilm matrix and are composed primarily of the major structural subunit CsgA. The CsgE chaperone facilitates the secretion of CsgA through CsgG by forming a cap at the base of the nonameric CsgG outer membrane pore. We elucidated a series of finely tuned nonpolar and charge-charge interactions that facilitate the oligomerization of CsgE and its ability to transport unfolded CsgA to CsgG for translocation.

Structure-based discovery of glycomimetic FmlH ligands as inhibitors of bacterial adhesion during urinary tract infection.

Treatment of bacterial infections is becoming a serious clinical challenge due to the global dissemination of multidrug antibiotic resistance, necessitating the search for alternative treatments to disarm the virulence mechanisms underlying these infections. Uropathogenic (UPEC) employs multiple chaperone-usher pathway pili tipped with adhesins with diverse receptor specificities to colonize various host tissues and habitats. For example, UPEC F9 pili specifically bind galactose or -acetylgalactosamine epitopes on the kidney and inflamed bladder.

Catheterization alters bladder ecology to potentiate infection of the urinary tract.

Methicillin-resistant (MRSA) is an emerging cause of catheter-associated urinary tract infection (CAUTI), which frequently progresses to more serious invasive infections. We adapted a mouse model of CAUTI to investigate how catheterization increases an individual's susceptibility to MRSA UTI. This analysis revealed that catheterization was required for MRSA to achieve high-level, persistent infection in the bladder.

Selective depletion of uropathogenic E. coli from the gut by a FimH antagonist.

Urinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) affect 150 million people annually. Despite effective antibiotic therapy, 30-50% of patients experience recurrent UTIs. In addition, the growing prevalence of UPEC that are resistant to last-line antibiotic treatments, and more recently to carbapenems and colistin, make UTI a prime example of the antibiotic-resistance crisis and emphasize the need for new approaches to treat and prevent bacterial infections.

Evolutionary fine-tuning of conformational ensembles in FimH during host-pathogen interactions.

Positive selection in the two-domain type 1 pilus adhesin FimH enhances fitness in urinary tract infection (UTI). We report a comprehensive atomic-level view of FimH in two-state conformational ensembles in solution, composed of one low-affinity tense (T) and multiple high-affinity relaxed (R) conformations. Positively selected residues allosterically modulate the equilibrium between these two conformational states, each of which engages mannose through distinct binding orientations.

Antibody-Based Therapy for Enterococcal Catheter-Associated Urinary Tract Infections.

Unlabelled: Gram-positive bacteria in the genus Enterococcus are a frequent cause of catheter-associated urinary tract infection (CAUTI), a disease whose treatment is increasingly challenged by multiantibiotic-resistant strains. We have recently shown that E. faecalis uses the Ebp pilus, a heteropolymeric surface fiber, to bind the host protein fibrinogen as a critical step in CAUTI pathogenesis.