Te xtbook proceduresr equiret he use of individual aptamerse nriched in SELEX libraries whicha re subsequentlyc hemically synthesized after their biochemical characterization. Here we show that this reduction of the available sequence space of large libraries and thus the diversity of binding molecules reduces the labellinge fficiency and fidelity of selected single aptamerst owards different strainso ft he human pathogen Pseudomonas aeruginosa compared to ap olyclonal aptamer librarye nriched by aw hole-cell-SELEX involving fluorescent aptamers.T he library outperformed single aptamersi nr eliable and specific targeting of different clinically relevants trains,a llowed to inhibitv irulence associatedc ellular functions and identification of bound cell surface targets by aptamer based affinity purification and mass spectrometry.T he stunning ease of this FluCell-SELEX and the convincing performance of the P. aeruginosa specific library may pave the way towards generally new and efficient diagnostic techniques based on polyclonal aptamer libraries not only in clinical microbiology.

Growth in biofilms as a fascinating and complex microbial lifestyle has become widely accepted as one of the key features of pathogenic microbes, to successfully express their full virulence potential and environmental persistence. This also increases the threat posed by Candida auris, which has a high intrinsic ability to persist on abiotic surfaces including those of surgical instruments and medical tubing. In a previous study, cyclic and helical-stabilized analogues of the antifungal peptide Cm-p5 were designed and synthetized, and proved to have increased activities against C. albicans and C. parapsilosis, but not against planktonic C. auris cells cultivated in suspension cultures. Here, we demonstrate, initially, that these derivatives, however, exhibited semi-inhibitory concentrations between 10–21 µg/mL toward C. auris biofilms. Maturated biofilms were also arrested between 71–97%. These novel biofilm inhibitors may open urgently needed new routes for the development of novel drugs and treatments for the next stage of fight against C. auris.

Based on their unique properties, oligonucleotide aptamers have been named a gift of biological chemistry to life science. We report the development of DNA aptamers as the first high-affinity binding molecules available for fast and rapid labeling of the human gut bacterium Akkermansia muciniphila with a certain impact on Alzheimer´s disease. Fast and reliable analyses of the composition of microbiomes is an emerging field in microbiology. We describe the molecular evolution and biochemical characterization of a specific aptamer library by a FluCell-SELEX and the characterization of specific molecules from the library by bioinformatics. The aptamer AKK13.1 exerted universal applicability in different analysis techniques in modern microbiology, including fluorimetry, confocal laser scanning microscopy and flow cytometry. It was also functional as a specific binding entity hybridized to anchor primers chemically coupled via acrydite-modification to the surface of a polyacrylamide-hydrogel, which can be prototypically used for the construction of affinity surfaces in sensor chips. Together, the performance and methodological flexibility of the aptamers presented here may open new routes not only to develop novel Akkermansia-specific assays for clinical microbiology and the analyses of human stool samples but may also be an excellent starting point for the construction of novel electronic biosensors.

Oligonucleotide DNA aptamers represent an emergently important class of binding entities towards as different analytes as small molecules or even whole cells. Without the canonical isolation of individual aptamers following...

The interplay between mesopore size and degree of peptide aggregation controls both calcitonin adsorption onto and release from mesoporous silica nanoparticles.