Thousands of yeasts have the potential for industrial application, though many were initially considered contaminants in the beer industry. However, these organisms are currently considered important components in beers because they contribute new flavors. Non-Saccharomyces wild yeasts can be important tools in the development of new products, and the objective of this work was to obtain and characterize novel yeast isolates for their ability to produce beer. Wild yeasts were isolated from environmental samples from Olympic National Park and analyzed for their ability to ferment malt extract medium and beer wort. Six different strains were isolated, of which Moniliella megachiliensis ONP131 displayed the highest levels of attenuation during fermentations. We found that M. megachiliensis could be propagated in common yeast media, tolerated incubation temperatures of 37 °C and a pH of 2.5, and was able to grow in media containing maltose as the sole carbon source. Yeast cultivation was considerably impacted (p < 0.05) by lactic acid, ethanol, and high concentrations of maltose, but ONP131 was tolerant to high salinity and hop acid concentrations. This is one of the first physiological characterizations of M. megachiliensis, which has potential for the production of beer and other fermented beverages.

Probiotics modulate the immune response and can increase the effectiveness of vaccines. Bacillus toyonensis is widely used as a probiotic in animal feed. The aim of this study was to assess the effects of B. toyonensis administration on the immune response to an experimental recombinant vaccine against bovine herpesvirus type 5 (BoHV-5) in mice. Mice were vaccinated with BoHV-5 recombinant glycoprotein D and supplemented with the probiotic B. toyonensis in two regimes: one group received the probiotic only during seven days prior to the initial vaccination while the second group was given the probiotic throughout the experimental period of seven weeks. Animals supplemented with probiotic B. toyonensis in two regimes showed an increase in total immunoglobulin (Ig)G, IgG1 and IgG2a levels in serum, in addition to higher titres of antibodies capable of neutralising the BoHV-5 virus than non-supplemented animals (P<0.05). Splenocytes from the supplemented mice had higher mRNA transcription levels of cytokines interleukin (IL)-4 and IL-12. These results show that the use of this probiotic may significantly contribute to the response elicited by recombinant vaccines, especially those that rely on increasing antibody and cell-mediated immune responses for efficacy. Further, the data support an immunomodulatory effect for probiotic B. toyonensis and imply that enhance effect on the immune response against a BoHV-5 recombinant vaccine in mice.

Mixed microbial cultures create sour beers but many brewers do not know which microbes comprise their cultures. The objective of this work was to use deep sequencing to identify microorganisms in sour beers brewed by spontaneous and non-spontaneous methods. Twenty samples were received from brewers, which were processed for microbiome analysis by next generation sequencing. For bacteria, primers were used to amplify the V3-V4 region of the 16S rRNA gene; fungal DNA detection was performed using primers to amplify the entire internal transcribed spacer region. The sequencing results were then used for taxonomy assignment, sample composition, and diversity analyses, as well as nucleotide BLAST searching. We identified 60 genera and 140 species of bacteria, of which the most prevalent were Lactobacillus acetotolerans, Pediococcus damnosus, and Ralstonia picketti/mannitolilytica. In fungal identification, 19 genera and 26 species were found, among which the most common yeasts were Brettanomyces bruxellensis and Saccharomyces cerevisiae. In some cases, genetic material from more than 60 microorganisms was found in a single sample. In conclusion, we were able to determine the microbiomes of various mixed cultures used to produce beer, providing useful information to better understand the sour beer fermentation process and brewing techniques.

Extracellular vesicles (EVs) play crucial roles in fungal communication and host immune modulation, representing potential therapeutic targets for fungal infections. This study investigated the role of fungal EVs in both intra- and interspecies communication, focusing on their effects on virulence and immune responses. Co-incubation experiments were performed using EVs derived from Candida albicans and Candidozyma auris to assess interactions with C. albicans planktonic cells and biofilms, as well as Cryptococcus neoformans and Cryptococcus gattii EVs interacting with C. neoformans cultures. EVs were observed associating with recipient cell surfaces, suggesting subsequent internalization. Functional assays revealed that EV exposure led to increased expression of CAP59, LAC1, URE1, and ERG11 genes, correlating with reduced antifungal susceptibility in both planktonic and biofilm forms. Additionally, EVs facilitated cross-species communication, enhancing biofilm adhesion and dispersion, which emphasizes their role in phenotypic modulation. Macrophages stimulated with fungal EVs exhibited receptor-specific gene expression changes (dependent on the EVs’ origin, including variation among species of the same genus), along with a pro-inflammatory phenotype marked by increased iNOS expression, enhanced TBK1/STAT1 production, and elevated levels of IL-1β, IL-6, and IL-8. Collectively, these findings underscore a critical role for fungal EVs in interspecies communication, biofilm regulation, and immune modulation, offering valuable insights into fungal pathogenicity mechanisms. IMPORTANCE: Currently, no vaccines exist to prevent fungal infections, underscoring the need for new therapies. As fungal diseases increase globally, understanding fungal biology is essential to identifying treatment targets. Fungi use extracellular vesicles (EVs) to communicate and evade immune responses. EVs mediate cell-cell communication, transporting proteins, polysaccharides, lipids, and nucleic acids, serving as “messages” exchanged within a fungal network. Understanding how these vesicles facilitate communication not only within a single species but also across different fungal species can shed light on their contribution to infection persistence and cross-species adaptability. Moreover, EVs may have a broader role in inter-kingdom signaling, influencing how fungi interact with host immune cells. The impact of fungal EVs on human innate immune responses remains a largely underexplored area, with significant gaps in our knowledge. This study aims to examine how fungal EVs affect immune responses and whether their signaling varies across species, potentially revealing new therapeutic targets.

Candida haemulonii comprises a group of pathogenic fungi with notable resistance to antifungal treatments and diagnostic challenges. The Candida haemulonii variety vulnera is of particular clinical importance due to its multidrug resistance and association with invasive infections, particularly in immunocompromised patients such as diabetics and neonates. Moreover, it has been implicated in hospital outbreaks, posing a significant challenge for infection control and antifungal treatment. Extracellular vesicles (EVs) released by these fungi play critical roles in pathogen-host interactions, potentially influencing antifungal resistance, immune evasion, and virulence. Previous studies conducted by our group have demonstrated that EVs carry immunogenic cargo that can influence the host's immune response. A comprehensive understanding of the molecular composition of these EVs is crucial for unraveling the mechanisms that govern resistance and virulence in C. haemulonii var. vulnera. This study characterizes the proteomic and miRNA-like cargo of EVs from C. haemulonii var. vulnera, revealing components that contribute to its adaptation and survival mechanisms. Proteomic analysis identified 124 EV-specific proteins, including BMH1, TEF1, CDC19, and PDC11, which are linked to processes such as metabolic adaptation, cell wall remodeling, and biofilm formation. miRNA-like molecules associated with mitochondrial function, such as the electron transport chain and regulation of the citric acid cycle, were also detected. These findings provide insights into EV-mediated molecular mechanisms driving fungal pathogenesis and resistance. By characterizing the EV cargo, this study highlights potential targets for antifungal therapies and offers a framework for understanding EV roles in fungal adaptation and pathogenicity. The Candida haemulonii complex poses significant clinical challenges due to its intrinsic resistance to conventional antifungal therapies and diagnostic complexities. This research explores the cargo of EVs released by C. haemulonii var. vulnera, revealing a selective mechanism for exporting proteins and RNA molecules critical to the fungus’ adaptation and survival in diverse environments. Proteomic and RNA analyses identified molecules involved in metabolic reprogramming, immune modulation, and stress response. These findings highlight the role of EVs in mediating host-pathogen interactions, facilitating immune evasion, and contributing to fungal virulence. Understanding the EV cargo expands our knowledge of fungal biology and underscores the therapeutic potential of targeting EV-associated molecules in antifungal strategies.