Liu X-Z, Wang Q-M, Theelen B, Groenewald M, Bai F-Y, Boekhout T
State Key Laboratory for Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China.
CBS Fungal Biodiversity Centre (CBS-KNAW), Uppsalalaan 8, Utrecht, The Netherlands.
Stud Mycol. 2015 Jun;81:1-26. doi: 10.1016/j.simyco.2015.08.001. Epub 2015 Oct 2.
The Tremellomycetes (Basidiomycota) contains a large number of unicellular and dimorphic fungi with stable free-living unicellular states in their life cycles. These fungi have been conventionally classified as basidiomycetous yeasts based on physiological and biochemical characteristics. Many currently recognised genera of these yeasts are mainly defined based on phenotypical characters and are highly polyphyletic. Here we reconstructed the phylogeny of the majority of described anamorphic and teleomorphic tremellomycetous yeasts using Bayesian inference, maximum likelihood, and neighbour-joining analyses based on the sequences of seven genes, including three rRNA genes, namely the small subunit of the ribosomal DNA (rDNA), D1/D2 domains of the large subunit rDNA, and the internal transcribed spacer regions (ITS 1 and 2) of rDNA including 5.8S rDNA; and four protein-coding genes, namely the two subunits of the RNA polymerase II (RPB1 and RPB2), the translation elongation factor 1-α (TEF1) and the mitochondrial gene cytochrome b (CYTB). With the consideration of morphological, physiological and chemotaxonomic characters and the congruence of phylogenies inferred from analyses using different algorithms based on different data sets consisting of the combined seven genes, the three rRNA genes, and the individual protein-coding genes, five major lineages corresponding to the orders Cystofilobasidiales, Filobasidiales, Holtermanniales, Tremellales, and Trichosporonales were resolved. A total of 45 strongly supported monophyletic clades with multiple species and 23 single species clades were recognised. This phylogenetic framework will be the basis for the proposal of an updated taxonomic system of tremellomycetous yeasts that will be compatible with the current taxonomic system of filamentous basidiomycetes accommodating the 'one fungus, one name' principle.
银耳纲（担子菌门）包含大量单细胞和双态真菌，它们在生命周期中具有稳定的自由生活单细胞状态。基于生理和生化特征，这些真菌传统上被归类为担子菌酵母。目前许多公认的这些酵母属主要基于表型特征定义，并且是高度多系的。在此，我们基于七个基因的序列，使用贝叶斯推断、最大似然法和邻接法分析，重建了大多数已描述的无性型和有性型银耳纲酵母的系统发育，这七个基因包括三个rRNA基因，即核糖体DNA（rDNA）的小亚基、大亚基rDNA的D1/D2结构域以及rDNA的内部转录间隔区（ITS 1和2），包括5.8S rDNA；以及四个蛋白质编码基因，即RNA聚合酶II的两个亚基（RPB1和RPB2）、翻译延伸因子1-α（TEF1）和线粒体基因细胞色素b（CYTB）。考虑到形态、生理和化学分类特征以及基于由七个基因组合、三个rRNA基因和单个蛋白质编码基因组成的不同数据集使用不同算法推断的系统发育的一致性，解析出了对应于囊丝酵母目、丝孢酵母目、霍尔特曼酵母目、银耳目和丝孢酵母目的五个主要谱系。共识别出45个得到强烈支持的包含多个物种的单系分支和23个单物种分支。这个系统发育框架将成为提出更新的银耳纲酵母分类系统的基础，该分类系统将与当前丝状担子菌的分类系统兼容，并遵循“一种真菌，一个名称”的原则。
