The Experts below are selected from a list of 12 Experts worldwide ranked by ideXlab platform
Cletus P. Kurtzman - One of the best experts on this subject based on the ideXlab platform.
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Relationships among genera of the Saccharomycotina (Ascomycota) from multigene phylogenetic analysis of type species
Fems Yeast Research, 2012Co-Authors: Cletus P. KurtzmanAbstract:Relationships among ascomycetous yeast genera (subphylum Saccharomycotina, phylum Ascomycota) have been uncertain. In the present study, type species of 70 currently recognized genera are compared from divergence in the nearly entire nuclear gene sequences for large subunit rRNA, small subunit (SSU) rRNA, translation elongation factor-1α, and RNA polymerase II, subunits 1 (RPB1) and 2 (RPB2). The analysis substantiates earlier proposals that all known ascomycetous yeast genera now assigned to the Saccharomycotina represent a single clade. Maximum likelihood analysis resolved the taxa into eight large multigenus clades and four-one- and two-genus clades. Maximum parsimony and neighbor-joining analyses gave similar results. Genera of the family Saccharomycetaceae remain as one large clade as previously demonstrated, to which the genus Cyniclomyces is now assigned. Pichia, Saturnispora, Kregervanrija, Dekkera, Ogataea and Ambrosiozyma are members of a single large clade, which is separate from the clade that includes Barnettozyma, Cyberlindnera, Phaffomyces, Starmera and Wickerhamomyces. Other clades include Kodamaea, Metschnikowia, Debaryomyces, Cephaloascus and related genera, which are separate from the clade that includes Zygoascus, Trichomonascus, Yarrowia and others. This study once again demonstrates that there is limited congruence between a system of classification based on phenotype and a system determined from DNA sequences.
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Cephaloascus hanawa 1920
The Yeasts (Fifth Edition), 2011Co-Authors: Cletus P. Kurtzman, Sybren G De HoogAbstract:Publisher Summary This chapter studies the genus Cephaloascus. In the determination of asexual reproduction, budding cells are usually present; pseudohyphae and true hyphae are prevalent. Blastoconidia are formed sympodially in short chains on large denticles; terminal blastoconidia are clavate. Colonies are smooth or farinose and white to pale cream-colored. In sexual reproduction, it is seen that ascophores are erect, hyaline or brown, and bear a cluster of asci at their apex. Asci arise in short, branched chains, are ellipsoidal, thin-walled, and open by apical deterioration; asci usually contain four hat-shaped ascospores. In physiology and biochemistry, it is seen that sugars may be weakly fermented. Nitrate is not assimilated. Coenzyme Q-9 is formed. The diazonium blue B reaction is negative. The chapter further examines the phylogenetic placement. The type of species mentioned is Cephaloascus fragrans. The species accepted are Cephaloascus albidus and Cephaloascus fragrans. The systematic discussion of the species includes growth on 4% malt extract/0.5% yeast extract agar, growth on the surface of assimilation media, formation of ascospores, CoQ, Mol% G1C, gene sequence accession number, type strain, cell carbohydrates, origin of the strain studied, complementary mating types, type strain, systematics, ecology, biotechnology, agriculture and food, and clinical importance.
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21 Cephaloascus hanawa
The Yeasts (Fourth Edition)#R##N#A Taxonomic Study, 1998Co-Authors: G S De Hoog, Cletus P. KurtzmanAbstract:Publisher Summary This chapter focuses on Cephaloascus genus and its constituent species. The colonies of this genus are smooth or farinose, and their color ranges from white to pale cream. Budding cells may be present and pseudomycelium and true hyphae are prevalent. Conidia are formed sympodially on large denticles in short chains and ultimate conidia are clavate. Ascophores are erect, hyaline or locally brown, and bear a cluster of asci at their apex. Asci arise in short, branched chains, ellipsoidal, thin-walled, and open by apical deterioration. They mostly contain 4 hat-shaped ascospores. The constituent species of this genus are Cephaloascus albidus and Cephaloascus fragrans. The ascophores of Cephaloascus albidus are erect, stout, hyaline, smooth and firm-walled. The Asci are formed in short chains in a terminal cluster on the ascophore and are thin-walled and ellipsoidal. Asci mostly contain 4 ascospores which are hat-shaped and open by apical deterioration. The ascophores of Cephaloascus fragrans are erect, stout, thick-walled, and often become rough-walled and golden brown in the apical part. Its asci are formed in short chains on metulae at the apex of ascophores, which open by deterioration at the tip.
P.a. Dixon - One of the best experts on this subject based on the ideXlab platform.
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Segregation of dwarf ascophore mutants in Cephaloascus fragrans
Transactions of The British Mycological Society, 2009Co-Authors: P.a. DixonAbstract:Dwarf ascophore mutants of Cephaloascus fragrans were produced by u.v. irradiation. The dwarf ascophore phenotype was due to a reduction in both cell number and cell length. In some strains the mutant ascophores were associated with a reduction in mycelial growth rate of 40–60% but in others the reduction was only 15–30%. In matings between different ascophore mutants wild-type ascophores were produced at the zone of contact indicating that they were determined by non-allelic recessive alleles. In crosses involving ascophore mutants, with wild-type mycelial growth rates, single ascophore cultures derived from hybrid spore-drops showed single gene segregation.
Sybren G De Hoog - One of the best experts on this subject based on the ideXlab platform.
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Cephaloascus hanawa 1920
The Yeasts (Fifth Edition), 2011Co-Authors: Cletus P. Kurtzman, Sybren G De HoogAbstract:Publisher Summary This chapter studies the genus Cephaloascus. In the determination of asexual reproduction, budding cells are usually present; pseudohyphae and true hyphae are prevalent. Blastoconidia are formed sympodially in short chains on large denticles; terminal blastoconidia are clavate. Colonies are smooth or farinose and white to pale cream-colored. In sexual reproduction, it is seen that ascophores are erect, hyaline or brown, and bear a cluster of asci at their apex. Asci arise in short, branched chains, are ellipsoidal, thin-walled, and open by apical deterioration; asci usually contain four hat-shaped ascospores. In physiology and biochemistry, it is seen that sugars may be weakly fermented. Nitrate is not assimilated. Coenzyme Q-9 is formed. The diazonium blue B reaction is negative. The chapter further examines the phylogenetic placement. The type of species mentioned is Cephaloascus fragrans. The species accepted are Cephaloascus albidus and Cephaloascus fragrans. The systematic discussion of the species includes growth on 4% malt extract/0.5% yeast extract agar, growth on the surface of assimilation media, formation of ascospores, CoQ, Mol% G1C, gene sequence accession number, type strain, cell carbohydrates, origin of the strain studied, complementary mating types, type strain, systematics, ecology, biotechnology, agriculture and food, and clinical importance.
G S De Hoog - One of the best experts on this subject based on the ideXlab platform.
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21 Cephaloascus hanawa
The Yeasts (Fourth Edition)#R##N#A Taxonomic Study, 1998Co-Authors: G S De Hoog, Cletus P. KurtzmanAbstract:Publisher Summary This chapter focuses on Cephaloascus genus and its constituent species. The colonies of this genus are smooth or farinose, and their color ranges from white to pale cream. Budding cells may be present and pseudomycelium and true hyphae are prevalent. Conidia are formed sympodially on large denticles in short chains and ultimate conidia are clavate. Ascophores are erect, hyaline or locally brown, and bear a cluster of asci at their apex. Asci arise in short, branched chains, ellipsoidal, thin-walled, and open by apical deterioration. They mostly contain 4 hat-shaped ascospores. The constituent species of this genus are Cephaloascus albidus and Cephaloascus fragrans. The ascophores of Cephaloascus albidus are erect, stout, hyaline, smooth and firm-walled. The Asci are formed in short chains in a terminal cluster on the ascophore and are thin-walled and ellipsoidal. Asci mostly contain 4 ascospores which are hat-shaped and open by apical deterioration. The ascophores of Cephaloascus fragrans are erect, stout, thick-walled, and often become rough-walled and golden brown in the apical part. Its asci are formed in short chains on metulae at the apex of ascophores, which open by deterioration at the tip.