Search bioRxiv⌕ Search

Biology subjects

De Vuyst, L.

Publications and source records attributed to De Vuyst, L..

6 recordsLinked to original sources

Decoding the microbiota of bors: multifunctional potential of a traditional Romanian beverage fermentation

Romanian bors, a traditional fermented wheat bran beverage, is produced through spontaneous fermentation and represents a complex microbial ecosystem. Despite its cultural importance and presumed health benefits, its microbial ecology and functional potential remain poorly characterized. The present study aimed to elucidate the microbial community structure of bors and link it to functional traits relevant to fermentation performance and food functionality by integrating culture-independent sequencing with culture-dependent isolation and functional characterization. A total of 32 bors samples (12 commercial and 20 homemade) were analyzed. Amplicon-based sequencing revealed a microbiome dominated by lactic acid bacteria (LAB), with lactobacilli accounting for the majority of the bacterial communities and Lactobacillus amylolyticus being identified as the most prevalent and abundant species. The yeast communities were mainly composed of fermentative taxa, including Pichia kudriavzevii and Kluyveromyces marxianus. Lactobacillus amylolyticus and P. kudriavzevii were also the most frequently isolated species among bacteria and yeasts, respectively. These results highlighted a strong adaptation of the microbial isolates to starch-rich cereal substrates and underscored the central role of these microorganisms in wheat bran fermentation for bors production. Whereas the sequencing-based analyses showed no significant differences in overall diversity between the commercial and homemade bors samples, the cultivation-based results indicated a higher bacterial richness in the commercial products. Notably, the culture-dependent method captured substantially fewer taxa, highlighting the complementary nature of the two approaches. Of a total of 101 bacterial strains (88 LAB and 13 acetic acid bacteria) isolated, many exhibited rapid growth and strong acidification capacity, reaching pH values below 4.5 within 12 h. A functional screening revealed that 21 % of these strains displayed -amylase activity, 65 % phytase activity, and 50 % {beta}-glucosidase activity, highlighting their capacity to metabolize cereal substrates and enhance the nutrient availability of bors. All strains showed antibacterial activity against at least one indicator bacterium tested, with a universal inhibition of Listeria monocytogenes. Overall, Romanian bors harbored a lactic acid bacteria-dominated core microbiome with a significant functional diversity. These findings underscored its potential as a rich source of functional and technologically important strains for application in starter and protective culture development.

microbiology↗

AutoSpectral improves spectral flow cytometry accuracy through optimised spectral unmixing and autofluorescence-matching at the cellular level

The advent of spectral flow cytometry has seen a rapid rise in the complexity of flow cytometry experiments, allowing the construction of assays with at least 50 fluorescent parameters. To correctly determine the contributions of each fluorophores signal to the high parameter data an accurate unmixing matrix needs to be generated. Even with single-stained controls, however, these matrixes include errors such as spillover spread, which compounds with each additional parameter, functionally limiting panel design. An additional source of errors is heterogeneity of cellular autofluorescence, which can affect both the unmixing matrix and misalign signals when the matrix is applied to individual cells in complex cell mixtures. Here we developed AutoSpectral, a statistical approach to automate the production of minimal-residual error unmixing matrixes and pair multiple distinct multifluorescent spectra to individual cells within a mixed sample, via an R-based software tool. AutoSpectral improves unmixing accuracy, improving incorrectly assigned cell positions by up to 9000-fold, reduces spread, particularly in samples with variable autofluorescence, and allows multi-lineage analysis of mixed populations, providing superior data for spectral flow cytometry experiments.

immunology↗

Rising together: Exploring Sourdough Fermentation Diversity through Co-design in the HealthFerm Citizen Science Initiative

Fermented foods are culturally significant and increasingly recognized for their potential health benefits, yet scientific data on household fermentation practices remain limited. We launched a co-designed citizen science (CS) initiative within the HealthFerm project to collect sourdough fermentation data across Europe. Over 1000 participants from 33 countries registered, with 671 samples submitted, enabling large-scale analysis of fermentation practices, motivations, and sourdough characteristics. Participants also completed standardized at-home experiments and sensory evaluations, generating a dataset linking baking habits with physicochemical and sensory profiles. Distinct patterns emerged: professional bakers used older, more frequently refreshed starters and fermented at higher temperatures. Ingredient choices and motivations varied by country, shaped by perceived health benefits. Beyond data collection, this initiative established a microbial biobank and harmonized metadata resource, while offering practical insights into co- design, logistics, and public engagement. The resulting framework provides a transferable model for participatory research in microbiology and food systems science.

scientific communication and education↗

Adults patients with autoinflammation of unknown origin partially phenocopy the immune presentation of Still's disease

Autoinflammation of unknown origin remains amongst the most enigmatic of systemic autoinflammatory disorders (SAIDs), immunological disorders characterized by inappropriate activation of the innate immune response. Recent clinical research has identified multiple distinct disorders, although overlap in clinical characteristics and genetic drivers impede rapid and precise diagnosis, and the immunological underpinning of disease is poorly understood. Here we aimed to understand the immunological process behind patients with autoinflammation of unknown origin. In a multi-center European trial, we collected samples from 36 patients with recent disease activity, and used deep immunophenotyping and plasma proteomics to compare to 58 healthy controls and an additional demographically-similar 92 SAID patients. Key immunological changes were upregulation of CD38 and HLA across T cell subsets and upregulation of acute phase plasma proteins in autoinflammation of unknown origin patients. These previously poorly characterised patients partially phenocopied the Stills disease presentation. Together this study identifies potential biomarkers and disease-mediators in autoinflammation of unknown origin.

immunology↗

Comparative genome analysis of Lactobacillus mudanjiangensis, an understudied member of the Lactobacillus plantarum group

The genus Lactobacillus is known to be extremely diverse and consists of different phylogenetic groups that show a diversity roughly equal to the expected diversity of a typical bacterial genus. One of the most prominent phylogenetic groups within this genus is the Lactobacillus plantarum group which contains the understudied Lactobacillus mudanjiangensis species. Before this study, only one L. mudanjiangensis strain, DSM 28402T, was described but without whole-genome analysis. In this study, three strains classified as L. mudanjiangensis, were isolated from three different carrot juice fermentations and their whole-genome sequence was determined, together with the genome sequence of the type strain. The genomes of all four strains were compared with publicly available L. plantarum group genome sequences. This analysis showed that L. mudanjiangensis harbored the second largest genome size and gene count of the whole L. plantarum group. In addition, all members of this species showed the presence of a gene coding for a putative cellulose-degrading enzyme. Finally, three of the four L. mudanjiangensis strains studied showed the presence of pili on scanning electron microscopy (SEM) images, which were linked to conjugative gene regions, coded on plasmids in at least two of the strains studied. Author summaryLactobacillus mudanjiangensis is an understudied species within the Lactobacillus plantarum group. Since its first description, no other studies have reported its isolation. Here, we present the first four genome sequences of this species, which include the genome sequence of the type strain and three new L. mudanjiangensis strains isolated from fermented carrot juice. The genomes of all four strains were compared with publicly available L. plantarum group genome sequences. We found that this species harbored the second largest genome size and gene count of the whole L. plantarum group. Furthermore, we present the first scanning electron microscopy (SEM) images of L. mudanjiangensis, which showed the formation of pili in three strains that we linked to genes related to conjugation. Finally, we found the presence of a unique putative cellulose-degrading enzyme, opening the door for different industrial applications of these Lactobacillus strains.

microbiology↗

Integrated culturing, modeling and transcriptomics uncovers complex interactions and emergent behavior in a synthetic gut community

Whereas the composition of the human gut microbiome is relatively well resolved, predictive understanding of its response to perturbations such as diet shifts is still lacking. Here, we followed a bottom-up strategy to explore human gut community dynamics. We established a synthetic community composed of three representative human gut isolates in well-controlled conditions in vitro. We then explored species interactions by performing all mono- and pair-wise fermentation experiments and quantified with a mechanistic community model how well tri-culture dynamics was predicted from mono-culture data. With the model as a reference, we demonstrated that species grown in co-culture behaved differently than in mono-culture and confirmed their altered behavior at the transcriptional level. In addition, we showed with replicate tri-cultures and in simulations that dominance in tri-culture sensitively depends on initial conditions. Our work has important implications for gut microbial community modeling as well as ecological interaction detection from batch cultures.

bioinformatics↗