Nguyen Nhu H, Suh Sung-Oui, Erbil Cennet K, Blackwell Meredith
Department of Biological Sciences, Louisiana State University, Baton Rouge, 70803, USA.
Mycol Res. 2006 Mar;110(Pt 3):346-56. doi: 10.1016/j.mycres.2005.11.010. Epub 2006 Feb 14.
Fourteen yeast isolates belonging to the Metschnikowia clade were isolated from the digestive tracts of lacewings (Neuroptera: Chrysopidae), soldier beetles and leaf beetles (Coleoptera: Cantharidae and Chrysomelidae), and a caddisfly (Trichoptera: Hydropsychidae). The insect hosts were associated with sugary substances of plants, a typical habitat for yeasts in this clade. Based on DNA sequence comparisons and phenetic characters, the yeasts were identified as Candida picachoensis, Candida pimensis, and four undescribed taxa. Among the undescribed taxa, three yeasts were distinguished from one another and from other described taxa by nucleotide differences in the ribosomal DNA repeat, which were sufficient to consider them as new species. Two of the novel yeast species are described as Metschnikowia noctiluminum (NRRL Y-27753(T)) and M. cornifloraespp. nov. (NRRL Y-27750(T)) based in part on production of needle-shaped ascospores, which are found in most Metschnikowia species. Sexual reproduction was not observed in the third new yeast, Candida chrysomelidarumsp. nov. (NRRL Y-27749(T)). A fourth isolate, NRRL Y-27752, was not significantly distinct from Metschnikowia viticola and Candida kofuensis to be described as a new species. Phylogenetic analysis of the D1/D2 loop sequences placed M. noctiluminum within the M. viticola clade, while C. chrysomelidarum was a sister taxon of Candida rancensis. Metschnikowia corniflorae was phylogenetically distinct from other new species and fell outside of the large-spored Metschnikowia group.
从草蛉（脉翅目：草蛉科）、步甲和叶甲（鞘翅目：花萤科和叶甲科）以及石蛾（毛翅目：纹石蛾科）的消化道中分离出了14株属于梅奇酵母分支的酵母菌株。这些昆虫宿主与植物的含糖物质有关，是该酵母分支的典型栖息地。基于DNA序列比较和表型特征，这些酵母被鉴定为皮卡乔念珠菌、皮门西斯念珠菌以及四个未描述的分类单元。在这些未描述的分类单元中，有三种酵母通过核糖体DNA重复序列中的核苷酸差异彼此区分开来，并与其他已描述的分类单元区分开来，这些差异足以将它们视为新物种。其中两种新酵母物种被描述为夜梅奇酵母（NRRL Y - 27753(T)）和新种玉米梅奇酵母（NRRL Y - 27750(T)），部分依据是产生针状子囊孢子，这在大多数梅奇酵母物种中都能发现。在第三种新酵母——新种叶甲念珠菌（NRRL Y - 27749(T)）中未观察到有性繁殖。第四个分离株NRRL Y - 27752与葡萄梅奇酵母和小府念珠菌没有显著差异，因此不能被描述为新物种。对D1/D2环序列的系统发育分析表明，夜梅奇酵母位于葡萄梅奇酵母分支内，而叶甲念珠菌是兰斯念珠菌的姐妹分类单元。玉米梅奇酵母在系统发育上与其他新物种不同，且不属于大孢子梅奇酵母组。
