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Mitochondrial DNA. Part B, Resources 2022The outbreak of milky disease of Chinese mitten crab caused by seriously restricted the development of the crab industry. In this study, the mitochondrial genome...
The outbreak of milky disease of Chinese mitten crab caused by seriously restricted the development of the crab industry. In this study, the mitochondrial genome sequence of was assembled, annotated, and further analyzed. The results indicated that the complete mitochondrial genome of was 75,095 bp, which contained two rRNAs, 23 tRNAs, and 13 protein-coding genes. The phylogenetic tree of 13 yeasts based on the complete mitochondrial genome was constructed which showed that (accession number OK514652) and (accession number MW147605.1) were clustered in a clade. To sum up, our research results would further provide essential data for the systematics and evolution study of .
PubMed: 35844974
DOI: 10.1080/23802359.2022.2097025 -
Frontiers in Microbiology 2022is a globally distributed pathogenic yeast with a wide range of aquatic hosts. A new strain, LNES0119, isolated from the Chinese mitten crab , has caused a serious...
is a globally distributed pathogenic yeast with a wide range of aquatic hosts. A new strain, LNES0119, isolated from the Chinese mitten crab , has caused a serious reduction in production and marked economic loss for the aquaculture industry in China. Therefore, the whole-genome sequence of LNES0119 was sequenced using Illumina and Oxford Nanopore technology; whole-genome annotation and comparative genomic analyses of this pathogen were performed as well. A high-quality genome of LNES0119 was 16.13 Mb in size, with six scaffolds and six contigs, and encoded 5,567 putative predicted genes. Of these, 1,467 genes shared substantial homology with genes in the pathogen-host interactions database. Comparative genomic analyses of three strains and one non-pathogenic yeast, aff. , showed 331 unique genes in LNES0119, 30 of which were putatively related to pathogenicity. Overall, we identified several meaningful characteristics related to pathogenicity and virulence that may play essential roles in the infection and pathogenicity of LNES0119. Our study will aid in identifying potential targets for further exploration of the molecular basis of the pathogenicity of as well as the therapeutic intervention of infection.
PubMed: 35770163
DOI: 10.3389/fmicb.2022.939141 -
Frontiers in Microbiology 2022Lipids are essential energy storage compounds and are the core structural elements of all biological membranes. During wine alcoholic fermentation, the ability of yeasts...
Lipids are essential energy storage compounds and are the core structural elements of all biological membranes. During wine alcoholic fermentation, the ability of yeasts to adjust the lipid composition of the plasma membrane partly determines their ability to cope with various fermentation-related stresses, including elevated levels of ethanol and the presence of weak acids. In addition, the lipid composition of grape juice also impacts the production of many wine-relevant aromatic compounds. Several studies have evaluated the impact of lipids and of their metabolism on fermentation performance and aroma production in the dominant wine yeast , but limited information is available on other yeast species. Thus, the aim of this study was to evaluate the influence of specific fatty acid and sterol mixtures on various non- yeast fermentation rates and the production of primary fermentation metabolites. The data show that the response to different lipid mixtures is species-dependent. For , a slight increase in carbon dioxide production was observed in media enriched with unsaturated fatty acids whereas fermented significantly better in synthetic media containing a higher concentration of polyunsaturated fatty acids than monounsaturated fatty acids. fermentation rate increased in media supplemented with lipids present at an equimolar concentration. The data indicate that these different responses may be linked to variations in the lipid profile of these yeasts and divergent metabolic activities, in particular the regulation of acetyl-CoA metabolism. Finally, the results suggest that the yeast metabolic footprint and ultimately the wine organoleptic properties could be optimized species-specific lipid adjustments.
PubMed: 35677913
DOI: 10.3389/fmicb.2022.823581 -
Scientific Reports Jun 2022The gut mycobiota has never been studied either during pregnancy or in patients with gestational diabetes (GDM). This study aimed to analyze the fecal mycobiota of GDM...
The gut mycobiota has never been studied either during pregnancy or in patients with gestational diabetes (GDM). This study aimed to analyze the fecal mycobiota of GDM patients during the second (T2) and third (T3) trimester of pregnancy and to compare it with the mycobiota of pregnant normoglycemic women (controls). Forty-one GDM patients and 121 normoglycemic women were studied. GDM mycobiota was composed almost exclusively by the Ascomycota phylum; Basidiomicota accounted for 43% of the relative frequency of the controls. Kluyveromyces (p < 0.001), Metschnikowia (p < 0.001), and Pichia (p < 0.001) showed a significantly higher frequency in GDM patients, while Saccharomyces (p = 0.019), were more prevalent in controls. From T2 to T3, a reduction in fungal alpha diversity was found in GDM patients, with an increase of the relative frequency of Candida, and the reduction of some pro-inflammatory taxa. Many associations between fungi and foods and nutrients were detected. Finally, several fungi and bacteria showed competition or co-occurrence. Patients with GDM showed a predominance of fungal taxa with potential inflammatory effects when compared to normoglycemic pregnant women, with a marked shift in their mycobiota during pregnancy, and complex bacteria-fungi interactions.
Topics: Bacteria; Diabetes, Gestational; Feces; Female; Humans; Pregnancy; Pregnancy Trimesters; Pregnant Women
PubMed: 35654937
DOI: 10.1038/s41598-022-13438-0 -
The Science of the Total Environment Aug 2022Pesticides are a major anthropogenic threat to the biodiversity of freshwater ecosystems, having the potential to affect non-target aquatic organisms and disrupt the...
Pesticides are a major anthropogenic threat to the biodiversity of freshwater ecosystems, having the potential to affect non-target aquatic organisms and disrupt the processes in which they intervene. Important knowledge gaps have been recognised concerning the ecological effects of synthetic fungicides on non-target symbiotic aquatic fungi and the ecological processes where they intervene. The goal of this work was to assess the influence of three commonly used fungicides (myclobutanil, metalaxyl and cymoxanil), which differ in their mode of action, on a host (the crustacean Daphnia magna) × parasite (the yeast Metschnikowia bicuspidata) experimental model. Using a set of life history experiments, we evaluated the effect of each fungicide on the outcome of this relationship (disease) and on the fitness of both host and parasite. Contrasting results were observed: (i) cymoxanil and metalaxyl were overall innocuous to host and parasite at the tested concentrations, although host reproduction was occasionally reduced in the simultaneous presence of parasite and fungicide; (ii) on the contrary, myclobutanil displayed a clear antifungal effect, decreasing parasite prevalence and alleviating infection signs in the hosts. This antiparasitic effect of myclobutanil was further investigated with a follow-up experiment that manipulated the timing of application of the fungicide, to understand which stage of parasite development was most susceptible: while myclobutanil did not interfere in the early stages of infection, its antifungal activity was clearly observable at a later stage of the disease (by impairing the production of transmission stages of the parasite). More research is needed to understand the broader consequences of this parasite-clearance effect, especially in face of increasing evidence that parasites are ecologically more important than their cryptic nature might suggest.
Topics: Agrochemicals; Animals; Antifungal Agents; Antiparasitic Agents; Daphnia; Ecosystem; Fungicides, Industrial; Metschnikowia; Parasites; Porifera
PubMed: 35429554
DOI: 10.1016/j.scitotenv.2022.155296 -
Biology Letters Apr 2022Parasites impose different selection regimes on their hosts, which respond by increasing their resistance and/or tolerance. Parental challenge with parasites can enhance...
Parasites impose different selection regimes on their hosts, which respond by increasing their resistance and/or tolerance. Parental challenge with parasites can enhance the immune response of their offspring, a phenomenon documented in invertebrates and termed transgenerational immune priming. We exposed two parental generations of the model organism to the horizontally transmitted parasitic yeast and recorded resistance- and tolerance-related traits in the offspring generation. We hypothesized that parentally primed offspring will increase either their resistance or their tolerance to the parasite. Our susceptibility assays revealed no impact of parental exposure on offspring resistance. Nonetheless, different fitness-related traits, which are indicative of tolerance, were altered. Specifically, maternal priming increased offspring production and decreased survival. Grandmaternal priming positively affected age at first reproduction and negatively affected brood size at first reproduction. Interestingly, both maternal and grandmaternal priming significantly reduced within-host-parasite proliferation. Nevertheless, primed for two consecutive generations had no competitive advantage in comparison to unprimed ones, implying additive maternal and grandmaternal effects. Our findings do not support evidence of transgenerational immune priming from bacterial infections in the same host species, thus, emphasizing that transgenerational immune responses may not be consistent even within the same host species.
Topics: Animals; Daphnia; Parasites
PubMed: 35382587
DOI: 10.1098/rsbl.2022.0018 -
Molecules (Basel, Switzerland) Mar 2022Pulcherrimin is a secondary metabolite of yeasts belonging to the clade, and pulcherrimin formation is responsible for the antimicrobial action of its producers....
Pulcherrimin is a secondary metabolite of yeasts belonging to the clade, and pulcherrimin formation is responsible for the antimicrobial action of its producers. Understanding the environmental function of this metabolite can provide insight into various microbial interactions and enables the efficient development of new effective bioproducts and methods. In this study, we evaluated the antimicrobial and antiadhesive action of yeast pulcherrimin, as well as its protective properties under selected stressful conditions. Classical microbiological plate methods, microscopy, and physico-chemical testing were used. The results show that pure pulcherrimin does not have antimicrobial properties, but its unique hydrophilic nature may hinder the adhesion of hydrophilic bacterial cells to abiotic surfaces. Pulcherrimin also proved to be a good cell protectant against UV-C radiation at both high and low temperatures.
Topics: Anti-Bacterial Agents; Bone Plates; Cold Temperature; Microbial Interactions; Microbiological Techniques
PubMed: 35335219
DOI: 10.3390/molecules27061855 -
American Journal of Botany Mar 2022Yeasts are often present in floral nectar and can influence plant fitness directly (independently of pollinators) or indirectly by influencing pollinator visitation and...
PREMISE
Yeasts are often present in floral nectar and can influence plant fitness directly (independently of pollinators) or indirectly by influencing pollinator visitation and behavior. However, few studies have assessed the effect of nectar yeasts on plant reproductive success or compared effects across different plant species, limiting our understanding of the relative impact of direct vs. indirect effects.
METHODS
We inoculated the nectar of six plant species in the field with the cosmopolitan yeast Metschnikowia reukaufii to analyze the direct and indirect effects on female reproductive success over 2 years. The pollinator assemblage for each species was recorded during both flowering years.
RESULTS
Direct yeast effects on female fecundity were statistically nonsignificant for all plant species. There were significant indirect, pollinator-mediated effects on fruit production and seed mass for the two species pollinated almost exclusively by bumblebees or hawkmoths, with the direction of the effects differing for the quantity- and quality-related fitness components. There were no consistent effects of the yeast on maternal fecundity for any of the species with diverse pollinator assemblages.
CONCLUSIONS
Effects of M. reukaufii on plant reproduction ranged from negative to neutral or positive depending on the plant species. The among-species variation in the indirect effects of nectar yeasts on plant pollination could reflect variation in the pollinator community, the specific microbes colonizing the nectar, and the order of microbial infection (priority effects), determining potential species interactions. Elucidating the nature of these multitrophic plant-pollinator-microbe interactions is important to understand complex processes underlying plant pollination.
Topics: Flowers; Plant Nectar; Plants; Pollination; Reproduction; Yeasts
PubMed: 35315515
DOI: 10.1002/ajb2.1834 -
Microbiology and Immunology Jun 2022Skin colonization by the emerging pathogen Candida auris is common in outbreaks within medical settings. Culture-based screening of patients is an effective management...
Skin colonization by the emerging pathogen Candida auris is common in outbreaks within medical settings. Culture-based screening of patients is an effective management strategy to control the pathogen, and the newly developed CHROMagar™ Candida Plus medium is claimed to enable the presumptive identification of C. auris. Here, we evaluated the use of this medium with 63 C. auris strains comprising its four well-established clades, as well as genetically related comparators, including species from the Metschnikowia clade. The colors and halos of both confluent growth and discrete colonies of all the tested strains were compared. It was found that on CHROMagar™ Candida Plus, C. auris formed characteristic white colonies with blue-green halos that were more evident after 72 hr of incubation at 35°C than after 48 hr. However, distinguishing between closely related species such as Candida haemulonii, Candida pseudohaemulonii, and Candida duobushaemulonii required the consideration of parameters other than color, including colony size and growth ability at 35°C. In conclusion, the novel chromogenic medium CHROMagar™ Candida Plus constitutes an easy screening tool for C. auris.
Topics: Agar; Antifungal Agents; Candida; Candida auris; Candidiasis; Humans
PubMed: 35229341
DOI: 10.1111/1348-0421.12973 -
Microorganisms Jan 2022() is responsible for grape infection and damage to the winemaking and table grape sectors. Although anti- chemicals are available, they are considered unsustainable...
BACKGROUND
() is responsible for grape infection and damage to the winemaking and table grape sectors. Although anti- chemicals are available, they are considered unsustainable for resistance phenomenon and adverse effects on the environment and human health. Research is focused on developing alternative approaches, such as exploiting biological control agents (BCAs). In this context, 19 yeasts of the genera , , , and were tested as antimicrobial agents against development.
METHODS
A combination of in vitro tests based on dual-culture methods, volatile organic compound production assay, laboratory tests on grape berries (punctured and sprayed with yeasts) and field experiments based on yeast treatments on grapes in vineyards allowed the selection of two potential BCAs.
RESULTS
DiSVA 269 and DiSVA 211 exhibited the best ability to contain the development of , showing the severity, the decay and the McKinney index lower than a commercial biological formulation consisting of a mixture of two different strains, which were used as positive controls.
CONCLUSIONS
The results indicated that the selected strains were effective BCA candidates to counteract in the field, applying them in the partial or total replacement of conventional treatments.
PubMed: 35208653
DOI: 10.3390/microorganisms10020200