The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Cletus P. Kurtzman - One of the best experts on this subject based on the ideXlab platform.
-
Phylogeny of the ascomycetous yeasts and the renaming of Pichia anomala to Wickerhamomyces anomalus
Antonie van Leeuwenhoek, 2011Co-Authors: Cletus P. KurtzmanAbstract:In this review, the phylogeny of the ascomycetous yeasts is discussed, with emphasis on the genus Pichia and its synonym Hansenula . The genus Pichia , as defined from phenotype, had nearly 100 assigned species, but the number of species has been reduced to 20 following phylogenetic circumscription on Pichia membranifaciens , the type species of the genus. The remaining species of Pichia have been reassigned to 20 different genera, many of which are newly described, such as Wickerhamomyces . The reason for reclassification of Pichia anomala in the genus Wickerhamomyces is discussed.
-
Systematics of methanol assimilating yeasts and neighboring taxa from multigene sequence analysis and the proposal of Peterozyma gen. nov., a new member of the Saccharomycetales
FEMS Yeast Research, 2010Co-Authors: Cletus P. Kurtzman, Christie J. RobnettAbstract:The relatedness among methanol-assimilating yeasts assigned to the genus Ogataea and neighboring taxa (Phylum Ascomycota , Subphylum Saccharomycotina , Class Saccharomycetes , Order Saccharomycetales ) was determined from phylogenetic analyses of gene sequences for nuclear large and small subunit (SSU) rRNAs, translation elongation factor-1α and mitochondrial SSU rRNA. On the basis of the analyses, Williopsis salicorniae and seven species of Pichia are proposed for transfer to the genus Ogataea , which has been emended, and Pichia angophorae , a nonhyphal species, is proposed for transfer to the mycelium forming genus Ambrosiozyma. Pichia toletana and Pichia xylosa form an independent lineage and are assigned to the genus Peterozyma , which is newly proposed.
-
Phylogenetic relationships among species of Pichia, Issatchenkia and Williopsis determined from multigene sequence analysis, and the proposal of Barnettozyma gen. nov., Lindnera gen. nov. and Wickerhamomyces gen. nov.
Fems Yeast Research, 2008Co-Authors: Cletus P. Kurtzman, Christie J. Robnett, Eleanor Basehoar-powersAbstract:Relationships among species assigned to the yeast genera Pichia, Issatchenkia and Williopsis, which are characterized by the ubiquinone CoQ-7 and inability to utilize methanol, were phylogenetically analyzed from nucleotide sequence divergence in the genes coding for large and small subunit rRNAs and for translation elongation factor-1alpha. From this analysis, the species separated into five clades. Species of Issatchenkia are members of the Pichia membranifaciens clade and are proposed for transfer to Pichia. Pichia dryadoides and Pichia quercuum are basal members of the genus Starmera. Williopsis species are dispersed among hat-spored taxa in each of the remaining three clades, which are proposed as the new genera Barnettozyma, Lindnera and Wickerhamomyces. Lineages previously classified as varieties of Pichia kluyveri, 'Issatchenkia'scutulata, Starmera amethionina and 'Williopsis'saturnus are elevated to species rank based on sequence comparisons.
-
Four new yeasts in the Pichia anomala clade
International Journal of Systematic and Evolutionary Microbiology, 2000Co-Authors: Cletus P. KurtzmanAbstract:Four new yeasts are described that were recognized as novel from nucleotide substitutions in domain D1/D2 of 26S rDNA, a region that is sufficiently divergent to allow resolution of most ascomycetous yeast species. The new species and their type strains are as follows: Pichia maclurae NRRL Y-5377T (= CBS 8671T); Pichia misumaiensis NRRL Y-17389T (= CBS 8062T); Candida mycetangii NRRL Y-6843T (= CBS 8675T); and Candida ulmi NRRL YB-2694T (= CBS 8670T). The two Pichia species form spherical ascospores and are heterothallic. Phylogenetic analysis of domain D1/D2 sequences placed the four new species in the Pichia anomala clade.
-
DNA relatedness among saturn-spored yeasts assigned to the generaWilliopsis andPichia
Antonie van Leeuwenhoek, 1991Co-Authors: Cletus P. KurtzmanAbstract:Saturn-spored species assigned to the genera Williopsis and Pichia were compared from extent of nuclear DNA complementarity. Of the Pichia spp., four were recognized as distinct taxa: P. dispora, P. saitoi, P. zaruensis and Pichia sp. nov. Among Williopsis spp., the following were accepted: W. californica, W. mucosa comb. nov., W. pratensis, W. saturnus var. saturnus, W. saturnus var. mrakii comb. nov., W. saturnus var. sargentensis comb. nov., W. saturnus var. subsufficiens comb. nov. and Williopsis sp. nov. The new Pichia and Williopsis species are described elsewhere. Moderate (36–68%) DNA relatedness was detected between the former Pichia sargentensis and varieties of W. saturnus again demonstrating that nitrate assimilation is not a reliable criterion for separating yeast species.
Johan Schnurer - One of the best experts on this subject based on the ideXlab platform.
-
biocontrol of mold growth in high moisture wheat stored under airtight conditions by Pichia anomala Pichia guilliermondii and saccharomyces cerevisiae
Applied and Environmental Microbiology, 1995Co-Authors: Stina Petersson, Johan SchnurerAbstract:Pichia anomala inhibits the growth of Penicillium roqueforti and Aspergillus candidus on agar. In this investigation, antagonistic activity on agar against 17 mold species was determined. The abilities of Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae to inhibit the growth of the mold Penicillium roqueforti in nonsterile high-moisture wheat were compared by adding 10(3) Penicillium roqueforti spores and different amounts of yeast cells per gram of wheat. Inoculated grain was packed in glass tubes, incubated at 25 degrees C with a restricted air supply, and the numbers of yeast and mold CFU were determined on selective media after 7 and 14 days. Pichia anomala reduced growth on agar plates for all of the mold species tested in a dose-dependent manner. Aspergillus fumigatus and Eurotium amstelodami were the most sensitive, while Penicillium italicum and Penicillium digitatum were the most resistant. Pichia anomala had the strongest antagonistic activity in wheat, with 10(5) and 10(6) CFU/g completely inhibiting the growth of Penicillium roqueforti. Inhibition was least pronounced at the optimum temperature (21 degrees C) and water activity (0.95) for the growth of Penicillium roqueforti. Pichia guilliermondii slightly reduced the growth of Penicillium roqueforti in wheat inoculated with 10(5) and 10(6) yeast CFU/g. S. cerevisiae inhibited mold growth only weakly at the highest inoculum level. Pichia anomala grew from 10(3) to 10(7) CFU/g of wheat in 1 week. To reach the same level, Pichia guilliermondii had to be inoculated at 10(4) CFU while S. cerevisiae required an inoculum of 10(5) CFU to reach 10(7) CFU/g of wheat.
-
Biocontrol of Mold Growth in High-Moisture Wheat Stored under Airtight Conditions by Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae (VOL 61, PG 1029, 1995)
Applied and Environmental Microbiology, 1995Co-Authors: Stina Petersson, Johan SchnurerAbstract:Biocontrol of Mold Growth in High-Moisture Wheat Stored under Airtight Conditions by Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae (VOL 61, PG 1029, 1995)
Richard E Goodman - One of the best experts on this subject based on the ideXlab platform.
-
evaluating potential risks of food allergy and toxicity of soy leghemoglobin expressed in Pichia pastoris
Molecular Nutrition & Food Research, 2018Co-Authors: Yuan Jin, Kwame Andohkumi, Rachel Z Fraser, Richard E GoodmanAbstract:cope : The Soybean (Glycine max) leghemoglobin c2 (LegHb) gene was introduced into Pichia pastoris yeast for sustainable production of a heme-carrying protein, for organoleptic use in plant-based meat. The potential allergenicity and toxicity of LegHb and 17 Pichia host-proteins each representing ≥1% of total protein in production batches were evaluated by literature review, bioinformatics sequence comparisons to known allergens or toxins, and in vitro pepsin digestion. Methods and results Literature searches found no evidence of allergenicity or toxicity for these proteins. There were no significant sequence matches of LegHb to known allergens or toxins. Eleven Pichia proteins had modest identity matches to minor environmental allergens and thirteen Pichia proteins had significant matches to proteins from toxic sources. Yet the matched allergens and toxins had similar matches to proteins from the commonly consumed yeast Saccharomyces cerevisiae, without evidence of food allergy or toxicity. The demonstrated history of safe use indicates additional tests for allergenicity and toxicity are not needed. The LegHb and Pichia sp. proteins were rapidly digested by pepsin at pH 2. Conclusion : These results demonstrate that foods containing recombinant soy LegHb produced in Pichia sp. are unlikely to present an unacceptable risk of allergenicity or toxicity to consumers. This article is protected by copyright. All rights reserved
Stina Petersson - One of the best experts on this subject based on the ideXlab platform.
-
biocontrol of mold growth in high moisture wheat stored under airtight conditions by Pichia anomala Pichia guilliermondii and saccharomyces cerevisiae
Applied and Environmental Microbiology, 1995Co-Authors: Stina Petersson, Johan SchnurerAbstract:Pichia anomala inhibits the growth of Penicillium roqueforti and Aspergillus candidus on agar. In this investigation, antagonistic activity on agar against 17 mold species was determined. The abilities of Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae to inhibit the growth of the mold Penicillium roqueforti in nonsterile high-moisture wheat were compared by adding 10(3) Penicillium roqueforti spores and different amounts of yeast cells per gram of wheat. Inoculated grain was packed in glass tubes, incubated at 25 degrees C with a restricted air supply, and the numbers of yeast and mold CFU were determined on selective media after 7 and 14 days. Pichia anomala reduced growth on agar plates for all of the mold species tested in a dose-dependent manner. Aspergillus fumigatus and Eurotium amstelodami were the most sensitive, while Penicillium italicum and Penicillium digitatum were the most resistant. Pichia anomala had the strongest antagonistic activity in wheat, with 10(5) and 10(6) CFU/g completely inhibiting the growth of Penicillium roqueforti. Inhibition was least pronounced at the optimum temperature (21 degrees C) and water activity (0.95) for the growth of Penicillium roqueforti. Pichia guilliermondii slightly reduced the growth of Penicillium roqueforti in wheat inoculated with 10(5) and 10(6) yeast CFU/g. S. cerevisiae inhibited mold growth only weakly at the highest inoculum level. Pichia anomala grew from 10(3) to 10(7) CFU/g of wheat in 1 week. To reach the same level, Pichia guilliermondii had to be inoculated at 10(4) CFU while S. cerevisiae required an inoculum of 10(5) CFU to reach 10(7) CFU/g of wheat.
-
Biocontrol of Mold Growth in High-Moisture Wheat Stored under Airtight Conditions by Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae (VOL 61, PG 1029, 1995)
Applied and Environmental Microbiology, 1995Co-Authors: Stina Petersson, Johan SchnurerAbstract:Biocontrol of Mold Growth in High-Moisture Wheat Stored under Airtight Conditions by Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae (VOL 61, PG 1029, 1995)
Feng-li Hui - One of the best experts on this subject based on the ideXlab platform.
-
Pichia nanzhaoensis sp. nov. and Pichia paraexigua f.a., sp. nov., two yeast species isolated from rotting wood.
International journal of systematic and evolutionary microbiology, 2018Co-Authors: Wan-li Gao, Kai-fang Liu, Lun-guang Yao, Feng-li HuiAbstract:Four yeast strains were isolated from rotting wood samples collected in the Baotianman Nature Reserve in Henan Province, Central China. On the basis of sequence analysis of the D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer regions, they were suggested to be two novel species of the genus Pichia. Pichia nanzhaoensis sp. nov. produces one to four spherical ascospores per ascus, and is most closely related to Candida pseudolambica. Pichia paraexigua f.a., sp. nov. is a sister taxa to Pichia exigua, but the formation of ascospores was not observed on various sporulation media. P. nanzhaoensis sp. nov. can weakly assimilate inulin, whereas P. paraexigua sp. nov. can weakly assimilate d-glucosamine. The type strain of Pichia nanzhaoensis is NYNU 178136T (=CICC 33279T=CBS 15346T) and the type strain of Pichia paraexigua is NYNU 178135T (=CICC 33278T=CBS 15237T).
