Ortho-Substituted α-Phenyl Mannoside Derivatives Promoted Early-Stage Adhesion and Biofilm Formation of E. coli 83972

Tackling catheter-associated urinary tract infections with next-generation antimicrobial technologies

Urinary catheters and other medical devices associated with the urinary tract such as stents are major contributors to nosocomial urinary tract infections (UTIs) as they provide an access path for pathogens to enter the bladder. Considering that catheter-associated urinary tract infections (CAUTIs) account for approximately 75% of UTIs and that UTIs represent the most common type of healthcare-associated infections, novel anti-infective device technologies are urgently required. The rapid rise of antimicrobial resistance in the context of CAUTIs further highlights the importance of such preventative strategies. In this review, the risk factors for pathogen colonization in the urinary tract are dissected, taking into account the nature and mechanistics of this unique environment. Moreover, the most promising next-generation preventative strategies are critically assessed, focusing in particular on anti-infective surface coatings. Finally, emerging approaches in this field and their likely clinical impact are examined.

Fimbria targeting superparamagnetic iron oxide nanoparticles enhance the antimicrobial and antibiofilm activity of ciprofloxacin against quinolone-resistant E. coli

High quinolone resistance of Escherichia coli limits the therapy options for urinary tract infection (UTI). In response to the urgent need for efficient treatment of multidrug-resistant infections, we designed a fimbriae targeting superparamagnetic iron oxide nanoparticle (SPION) delivering ciprofloxacin to ciprofloxacin-resistant E. coli. Bovine serum albumin (BSA) conjugated poly(acrylic acid) (PAA) coated SPIONs (BSA@PAA@SPION) were developed for encapsulation of ciprofloxacin and the nanoparticles were tagged with 4-aminophenyl-α-D-mannopyrannoside (mannoside, Man) to target E. coli fimbriae. Ciprofloxacin-loaded mannoside tagged nanoparticles (Cip-Man-BSA@PAA@SPION) provided high antibacterial activity (97.1 and 97.5%, respectively) with a dose of 32 μg/mL ciprofloxacin against two ciprofloxacin-resistant E. coli isolates. Furthermore, a strong biofilm inhibition (86.9% and 98.5%, respectively) was achieved in the isolates at a dose 16 and 8 times lower than the minimum biofilm eradication concentration (MBEC) of ciprofloxacin. Weaker growth inhibition was observed with untargeted nanoparticles, Cip-BSA@PAA@SPIONs, confirming that targeting E. coli fimbria with mannoside-tagged nanoparticles increases the ciprofloxacin efficiency to treat ciprofloxacin-resistant E. coli. Enhanced killing activity against ciprofloxacin-resistant E. coli planktonic cells and strong growth inhibition of their biofilms suggest that Cip-Man-BSA@PAA@SPION system might be an alternative and/or complementary therapeutic option for the treatment of quinolone-resistant E. coli infections.

Comprehensive spectral libraries for various rabbit eye tissue proteomes

Rabbits have been widely used for studying ocular physiology and pathology due to their relatively large eye size and similar structures with human eyes. Various rabbit ocular disease models, such as dry eye, age-related macular degeneration, and glaucoma, have been established. Despite the growing application of proteomics in vision research using rabbit ocular models, there is no spectral assay library for rabbit eye proteome publicly available. Here, we generated spectral assay libraries for rabbit eye compartments, including conjunctiva, cornea, iris, retina, sclera, vitreous humor, and tears using fractionated samples and ion mobility separation enabling deep proteome coverage. The rabbit eye spectral assay library includes 9,830 protein groups and 113,593 peptides. We present the data as a freely available community resource for proteomic studies in the vision field. Instrument data and spectral libraries are available via ProteomeXchange with identifier PXD031194.

Measurement(s)	database type spectral library
Technology Type(s)	ion mobility spectrometry-mass spectrometry
Sample Characteristic - Organism	Oryctolagus cuniculus
Sample Characteristic - Environment	eye
Sample Characteristic - Location	United States of America

Positively-charged microcrystalline cellulose microparticles: Rapid killing effect on bacteria, trapping behavior and excellent elimination efficiency of biofilm matrix from water environment

Pathogen and biofilm contamination in aqueous systems leave millions of people at risk of waterborne diseases. Herein, to address this issue, a green and highly efficient strategy is developed to concurrently trap and kill bacteria, eliminate the debris and the existing biofilm matrix in water environment via magnetic microparticles. The particles (TPFPs) were prepared from the in-situ deposition of Fe₃O₄ nanoparticles onto the surface of antibacterial functionalized microcrystalline cellulose (MCC). Noticeably, TPFPs can completely inactivate both S. aureus and E. coli once contacting for 30 min by disrupting the bacterial membrane. Meanwhile, the MCC-based magnetic particles retained 100% biocidal efficiency against E. coli (5 * 10⁴E. coli/mg particles) during ten recycling procedures without any treatment. More importantly, according to the results of trapping behavior and antibiofilm assays, not only bacteria could be captured by the particles (trapping rate was over 85%), but also the residual debris from dead bacteria and fragmented biofilm was together removed based on the special structure and functions of the antibacterial particles (~ 80%), including extremely rough surfaces, surficial positive charge and magneto-responsive property. This study presents an efficient approach for microorganism management in water system which can be expectantly applied to improve the water safety.