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Quirico Migheli - One of the best experts on this subject based on the ideXlab platform.
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Proteome changes during yeast-like and pseudohyphal growth in the biofilm-forming yeast Pichia fermentans
Amino Acids, 2015Co-Authors: Biancaelena Maserti, Alessandra Podda, Lucia Giorgetti, Renata Carratore, Didier Chevret, Quirico MigheliAbstract:The Pichia fermentans strain DISAABA 726 is a biofilm-forming yeast that has been proposed as biocontrol agent to control brown rot on apple. How ever, when inoculated on peach, strain 726 shows yeast-like to pseudohyphal transition coupled to a pathogenic behaviour. To identify the proteins potentially involved in such transition process, a comparative proteome analysis of P. fermentans 726 developed on peach (filamentous growth) vs apple (yeast-like growth) was carried out using two-dimensional gel electrophoresis coupled with mass spectrometry analysis. The proteome comparison was also performed between the two different cell morphologies induced in a liquid medium amended with urea (yeast-like cells) or methionine (filamentous cells) to exclude fruit tissue impact on the transition. Seventy-three protein spots showed significant variations in abundance (±twofold, p
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Proteome changes during yeast-like and pseudohyphal growth in the biofilm-forming yeast Pichia fermentans
Amino Acids, 2015Co-Authors: Biancaelena Maserti, Alessandra Podda, Lucia Giorgetti, Didier Chevret, Renata Del Carratore, Quirico MigheliAbstract:The Pichia fermentans strain DISAABA 726 is a biofilm-forming yeast that has been proposed as biocontrol agent to control brown rot on apple. How ever, when inoculated on peach, strain 726 shows yeast-like to pseudohyphal transition coupled to a pathogenic behaviour. To identify the proteins potentially involved in such transition process, a comparative proteome analysis of P. fermentans 726 developed on peach (filamentous growth) vs apple (yeast-like growth) was carried out using two-dimensional gel electrophoresis coupled with mass spectrometry analysis. The proteome comparison was also performed between the two different cell morphologies induced in a liquid medium amended with urea (yeast-like cells) or methionine (filamentous cells) to exclude fruit tissue impact on the transition. Seventy-three protein spots showed significant variations in abundance (+/- twofold, p < 0.01, confidence intervals 99 %) between pseudohyphal vs yeast-like morphology produced on fruits. Among them, 30 proteins changed their levels when the two morphologies were developed in liquid medium. The identified proteins belong to several pathways and functions, such as glycolysis, amino acid synthesis, chaperones, and signalling transduction. The possible role of a group of proteins belonging to the carbohydrate pathway in the metabolic re-organisation during P. fermentans dimorphic transition is discussed.
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A putative phospholipase C is involved in Pichia fermentans dimorphic transition.
Biochimica et biophysica acta, 2013Co-Authors: Maria Lina Sanna, Giacomo Zara, Severino Zara, Quirico Migheli, Marilena Budroni, Ilaria Maria MannazzuAbstract:Abstract Background Pichia fermentans DiSAABA 726 is a dimorphic yeast that reversibly shifts from yeast-like to pseudohyphal morphology. This yeast behaves as a promising antagonist of Monilia spp. in the yeast-like form, but becomes a destructive plant pathogen in the pseudohyphal form thus raising the problem of the biological risk associated with the use of dimorphic yeasts as microbial antagonists in the biocontrol of phytopathogenic fungi. Methods Pichia fermentans DiSAABA 726 was grown in urea- and methionine-containing media in order to induce and separate yeast-like and pseudohyphal morphologies. Total RNA was extracted from yeast-like cells and pseudohyphae and retro-transcribed into cDNA. A rapid subtraction hybridization approach was utilized to obtain the cDNA sequences putatively over-expressed during growth on methionine-containing medium and involved in pseudohyphal transition. Results Five genes that are over-expressed during yeast-like/pseudohyphal dimorphic transition were isolated. One of these, encoding a putative phospholipase C, is involved in P. fermentans filamentation. In fact, while the inhibition of phospholipase C, by means of 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphorylcholine (Et-18), is accompanied by a significant reduction of pseudohyphae formation in P. fermentans, the addition of exogenous cAMP fully restores pseudohyphal growth also in the presence of Et-18. Conclusion Phospholipase C is part of a putative “methionine sensing machinery” that activates cAMP-PKA signal transduction pathway and controls P. fermentans yeast-like/pseudohyphal dimorphic transition. General significance Phospholipase C is a promising molecular target for further investigations into the link between pseudohyphae formation and pathogenicity in P. fermentans.
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Identification of differentially expressed genes associated with changes in the morphology of Pichia fermentans on apple and peach fruit
FEMS yeast research, 2012Co-Authors: Stefano Fiori, Marilena Budroni, Ilaria Maria Mannazzu, Barbara Scherm, Jia Liu, Robert E. Farrell, Bianca E. Maserti, Michael Wisniewski, Quirico MigheliAbstract:Pichia fermentans (strain DISAABA 726) is an effective biocontrol agent against Monilinia fructicola and Botrytis cinerea when inoculated in artificially wounded apple fruit but is an aggressive pathogen when inoculated on wounded peach fruit, causing severe fruit decay. Pichia fermentans grows as budding yeast on apple tissue and exhibits pseudohyphal growth on peach tissue, suggesting that dimorphism may be associated with pathogenicity. Two complementary suppressive subtractive hybridization (SSH) strategies, that is, rapid subtraction hybridization (RaSH) and PCR-based subtraction, were performed to identify genes differentially expressed by P. fermentans after 24-h growth on apple vs. peach fruit. Gene products that were more highly expressed on peach than on apple tissue, or vice versa, were sequenced and compared with available yeast genome sequence databases. Several of the genes more highly expressed, when P. fermentans was grown on peach, were related to stress response, glycolysis, amino acid metabolism, and alcoholic fermentation but surprisingly not to cell wall degrading enzymes such as pectinases or cellulases. The dual activity of P. fermentans as both a biocontrol agent and a pathogen emphasizes the need for a thorough risk analysis of potential antagonists to avoid unpredictable results that could negatively impact the safe use of postharvest biocontrol strategies.
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Pichia fermentans dimorphic changes depend on the nitrogen source.
Fungal biology, 2012Co-Authors: Maria Lina Sanna, Giacomo Zara, Severino Zara, Quirico Migheli, Marilena Budroni, Ilaria Maria MannazzuAbstract:Pichia fermentans DiSAABA 726 is a biofilm-forming yeast that undergoes dimorphic transition. Under yeast-like morphology it controls brown rot caused by Monilia spp. on apple fruit, while under pseudohyphal form, it shows pathogenic behaviour itself on peach fruit. The present study investigates the nutritional factors that induce and separate yeast-like and pseudohyphal morphologies under laboratory conditions. We show that P. fermentans DiSAABA 726 produces mainly yeast-like cells on media containing millimolar concentrations of urea and diammonium phosphate, and forms pseudohyphae at micromolar concentrations of these two salts. With ammonium sulphate, yeast-like or pseudohyphal morphology depends on the N concentration and the pH of the culture media. Amino acids such as methionine, valine, and phenylalanine invariably induce pseudohyphal morphology irrespective of the N concentration and the pH of the culture media. Methionol, 1-butanol, isobutanol, and isopropanol induce pseudohyphal growth, while phenylethanol and isoamyl alcohol fail to induce the formation of filaments. Thus, the morphogenesis of P. fermentans DiSAABA 726 depends more on the nitrogen source than on the N concentration, and is regulated by the quorum-sensing molecules that are generally produced from amino-acid assimilation under nitrogen starvation.
Baltasar Mayo - One of the best experts on this subject based on the ideXlab platform.
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Candida cabralensis sp. nov., a yeast species isolated from traditional Spanish blue-veined Cabrales cheese.
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Ana Belén Flórez, Carmela Belloch, Pablo Álvarez-martín, Amparo Querol, Baltasar MayoAbstract:Three yeast strains, 1AD8T, 3AD15 and 3AD23, belonging to a previously unknown yeast species were isolated from two independent batches of the Spanish blue-veined Cabrales cheese, a traditional cheese manufactured without the addition of starter and mould cultures. Physiological characterization revealed that the unknown yeast is not fermentative and does not assimilate lactose; rather it assimilates dl-lactic acid and ethanol, major end products of lactic acid bacteria metabolism in cheese. The novel yeast is anamorphic. Phylogenetic tree reconstruction based on nucleotide sequence comparison of the D1/D2 region of the 26S rRNA gene showed that Pichia terricola and Pichia fermentans are the closest relatives of the unknown species. The name Candida cabralensis sp. nov. is proposed, and the isolate 1AD8T (=CECT 13027T =CBS 11679T) is the type strain of this novel taxon.
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Phenotypic and molecular identification of yeast species associated with Spanish blue-veined Cabrales cheese
International Dairy Journal, 2007Co-Authors: Pablo Álvarez-martín, Ana Belén Flórez, Teresa-maría López-díaz, Baltasar MayoAbstract:Abstract Classification of 74 yeasts isolated during manufacture and ripening of Cabrales cheese was attemped by phenotypic and molecular methods. Phenotypic classification included the use of commercial kits and classical biochemical analyses. Molecular classification was performed by restriction fragment length polymorphism (RFLP) of the ITS1-5.8S-ITS2 region, sequencing and comparison of the sequences in databases. Forty-one isolates were identified by phenotypic tests, including strains of Debaryomyces hansenii (14 isolates), Kluyveromyces lactis (11 isolates) and Pichia fermentans (9 isolates). The identification was confirmed by the HaeIII and HinfI RFLP profiles and comparison of their corresponding nucleotide sequences. The phenotypic classification failed to identify many other species; 16 isolates assigned to Zygosaccharomyces were genetically related to Pichia (13 isolates) and Saccharomyces (3 isolates). Classification of a few isolates was not possible, either because yeast species are new or a lack of sequences for this region in databases.
Yong-sheng Tao - One of the best experts on this subject based on the ideXlab platform.
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Increased glycosidase activities improved the production of wine varietal odorants in mixed fermentation of P. fermentans and high antagonistic S. cerevisiae
Food chemistry, 2020Co-Authors: Qian-qian Wang, Yong-sheng TaoAbstract:Abstract A selected Pichia fermentans strain was simultaneously and sequentially inoculated in synthetic and real juice with S. cerevisiae strains of different antagonistic activities in a ratio 1:1 to observe the correlation between varietal odorants and glycosidase activities. Fermentations using pure S. cerevisiae strains were used for comparison. Yeast biomass and glycosidase activities were monitored, varietal odorants were detected using HS-SPME-GC/MS during fermentation. The final wine aroma attributes were analyzed by trained panelists. Results showed that co-inoculation with high antagonistic S. cerevisiae resulted in higher glycosidase activities than others. Pearson correlation analysis indicated that yeast biomass was positively related to glycosidase activities during fermentation. The increase in glycosidase activities was the main reason for the higher production of terpenes and C13-norisoprenoids, and for the lower C6 compound content, which lead to superior fruity and floral aromas in the final wine samples of the high antagonistic S. cerevisiae group.
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Evolution of volatile compounds treated with selected non-Saccharomyces extracellular extract during Pinot noir winemaking in monsoon climate
Food research international (Ottawa Ont.), 2019Co-Authors: Cai-lin Kong, Guo-jie Jin, Xiao-lin Zhu, Yong-sheng TaoAbstract:Abstract The dynamic pattern of volatiles during Pinot Noir winemaking in monsoon climate with yeast extracellular extract (EE) treatment was analyzed. EE from selected Pichia fermentans and Rhodotorula mucilaginosa strains, and almond β-glucosidase were added after 12-h alcohol fermentation, and the volatiles were determined every 24 h by GC–MS. After 6-month storage, wine aroma was evaluated instrumentally as well as by well-trained panelists. Results showed that enzyme treatments improved the contents of both varietal and fermentative volatiles. The levels of C6 compounds, terpenes, and higher alcohols increased constantly during alcohol fermentation, whereas acetates, short and medium chain fatty acid ethyl esters, phenylethyls, and fatty acids increased first, followed by gradual decrease. EE treatment retarded the decrease of fruity ester content in wine. Mathematical regression between wine aroma and volatiles showed that the relatively higher contents of acetates, ethyl esters, and C13-norisoprenoids in 6-month EE-treated wine were responsible for the improvement in floral aroma intensity.
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Flavor modification of dry red wine from Chinese spine grape by mixed fermentation with Pichia fermentans and S. cerevisiae
LWT, 2019Co-Authors: Cai-lin Kong, Xing-chen Wang, Chao-qi Chen, Yong-sheng TaoAbstract:Abstract Mixed fermentation of Pichia fermentans and Saccharomyces cerevisiae was designed to circumvent the problem of weak aroma in Chinese spine grape wines. Spine grape, “Xiang Pearl”, was used for wine production by red wine-making processes. Physicochemical indices were measured using titratable and spectroscopic methodologies. Volatiles were quantified by SPME-GC-MS, and aroma attributes were analyzed by trained panelists. Results showed mixed fermentation benefited color properties by improving total anthocyanin, polymeric anthocyanin, and total tannin contents. The content of varietal compounds, except those of thiols, were reduced, whereas fermentative compounds contents, especially those of higher alcohols, esters, and phenylethyls, were increased by mixed fermentation. Sensory analysis showed mixed fermentation enhanced fruity and floral traits in wine; this was confirmed by mathematical regression showing elevated levels of fermentative volatiles dominated the contribution to pleasant aroma, whereas reduced content of varietal compounds, with the exception of thiols, correlated negatively with favorable characteristics.
Ana Belén Flórez - One of the best experts on this subject based on the ideXlab platform.
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Candida cabralensis sp. nov., a yeast species isolated from traditional Spanish blue-veined Cabrales cheese.
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Ana Belén Flórez, Carmela Belloch, Pablo Álvarez-martín, Amparo Querol, Baltasar MayoAbstract:Three yeast strains, 1AD8T, 3AD15 and 3AD23, belonging to a previously unknown yeast species were isolated from two independent batches of the Spanish blue-veined Cabrales cheese, a traditional cheese manufactured without the addition of starter and mould cultures. Physiological characterization revealed that the unknown yeast is not fermentative and does not assimilate lactose; rather it assimilates dl-lactic acid and ethanol, major end products of lactic acid bacteria metabolism in cheese. The novel yeast is anamorphic. Phylogenetic tree reconstruction based on nucleotide sequence comparison of the D1/D2 region of the 26S rRNA gene showed that Pichia terricola and Pichia fermentans are the closest relatives of the unknown species. The name Candida cabralensis sp. nov. is proposed, and the isolate 1AD8T (=CECT 13027T =CBS 11679T) is the type strain of this novel taxon.
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Phenotypic and molecular identification of yeast species associated with Spanish blue-veined Cabrales cheese
International Dairy Journal, 2007Co-Authors: Pablo Álvarez-martín, Ana Belén Flórez, Teresa-maría López-díaz, Baltasar MayoAbstract:Abstract Classification of 74 yeasts isolated during manufacture and ripening of Cabrales cheese was attemped by phenotypic and molecular methods. Phenotypic classification included the use of commercial kits and classical biochemical analyses. Molecular classification was performed by restriction fragment length polymorphism (RFLP) of the ITS1-5.8S-ITS2 region, sequencing and comparison of the sequences in databases. Forty-one isolates were identified by phenotypic tests, including strains of Debaryomyces hansenii (14 isolates), Kluyveromyces lactis (11 isolates) and Pichia fermentans (9 isolates). The identification was confirmed by the HaeIII and HinfI RFLP profiles and comparison of their corresponding nucleotide sequences. The phenotypic classification failed to identify many other species; 16 isolates assigned to Zygosaccharomyces were genetically related to Pichia (13 isolates) and Saccharomyces (3 isolates). Classification of a few isolates was not possible, either because yeast species are new or a lack of sequences for this region in databases.
Pablo Álvarez-martín - One of the best experts on this subject based on the ideXlab platform.
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Candida cabralensis sp. nov., a yeast species isolated from traditional Spanish blue-veined Cabrales cheese.
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Ana Belén Flórez, Carmela Belloch, Pablo Álvarez-martín, Amparo Querol, Baltasar MayoAbstract:Three yeast strains, 1AD8T, 3AD15 and 3AD23, belonging to a previously unknown yeast species were isolated from two independent batches of the Spanish blue-veined Cabrales cheese, a traditional cheese manufactured without the addition of starter and mould cultures. Physiological characterization revealed that the unknown yeast is not fermentative and does not assimilate lactose; rather it assimilates dl-lactic acid and ethanol, major end products of lactic acid bacteria metabolism in cheese. The novel yeast is anamorphic. Phylogenetic tree reconstruction based on nucleotide sequence comparison of the D1/D2 region of the 26S rRNA gene showed that Pichia terricola and Pichia fermentans are the closest relatives of the unknown species. The name Candida cabralensis sp. nov. is proposed, and the isolate 1AD8T (=CECT 13027T =CBS 11679T) is the type strain of this novel taxon.
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Phenotypic and molecular identification of yeast species associated with Spanish blue-veined Cabrales cheese
International Dairy Journal, 2007Co-Authors: Pablo Álvarez-martín, Ana Belén Flórez, Teresa-maría López-díaz, Baltasar MayoAbstract:Abstract Classification of 74 yeasts isolated during manufacture and ripening of Cabrales cheese was attemped by phenotypic and molecular methods. Phenotypic classification included the use of commercial kits and classical biochemical analyses. Molecular classification was performed by restriction fragment length polymorphism (RFLP) of the ITS1-5.8S-ITS2 region, sequencing and comparison of the sequences in databases. Forty-one isolates were identified by phenotypic tests, including strains of Debaryomyces hansenii (14 isolates), Kluyveromyces lactis (11 isolates) and Pichia fermentans (9 isolates). The identification was confirmed by the HaeIII and HinfI RFLP profiles and comparison of their corresponding nucleotide sequences. The phenotypic classification failed to identify many other species; 16 isolates assigned to Zygosaccharomyces were genetically related to Pichia (13 isolates) and Saccharomyces (3 isolates). Classification of a few isolates was not possible, either because yeast species are new or a lack of sequences for this region in databases.