Park Jong Soo
Department of Oceanography, Research Institute for Dok-do and Ulleung-do Island and Kyungpook Institute of Oceanography, School of Earth System Sciences, Kyungpook National University, 80 Daehakro, Bukgu, Daegu, 41566, Korea.
J Eukaryot Microbiol. 2017 Nov;64(6):771-778. doi: 10.1111/jeu.12409. Epub 2017 Apr 6.
The genus Tetramitus is a representative amoeboflagellate group within the Heterolobosea, and currently contains over a dozen species. Here, a new heterolobosean amoeboflagellate was isolated from a freshwater pond on Dokdo Island, Korea. The amoebae have eruptive pseudopodia, no uroidal filament, and a nucleus with a central nucleolus. The length and width of the amoebae are 15.5-28.0 μm and 5.4-12.6 μm, respectively. The flagellates are conical, with 4 flagella of equal length (~10 μm). There is a discrete rostrum in the subapical region of the flagellate form. The cyst has thin endo- and ectocyst layers and no cyst pores. The amoeba shows slow movement at 37 °C, but does not move at 42 °C under a light microscope. Phylogenies of the 18S rRNA gene and the ITS1-5.8S rRNA gene-ITS2 sequence show that the strain belongs to a subclade of Tetramitus that includes Tetramitus rostratus, Tetramitus waccamawensis and Tetramitus entericus, amongst others. Nonetheless, the strain is distinct from other species in both molecular phylogenetic trees. Thus the strain isolated from the Dokdo Island is proposed as a novel species, Tetramitus dokdoensis n. sp.
四膜虫属是异叶足虫纲中的一个代表性变形鞭毛虫类群，目前包含十多个物种。在此，从韩国独岛的一个淡水池塘中分离出一种新的异叶足虫纲变形鞭毛虫。该变形虫具有喷发式伪足，无尾状丝，细胞核有一个位于中央的核仁。变形虫的长度和宽度分别为15.5 - 28.0微米和5.4 - 12.6微米。鞭毛虫呈圆锥形，有4条等长（约10微米）的鞭毛。在鞭毛虫形态的亚顶端区域有一个离散的喙。包囊有薄的内膜和外膜层，无包囊孔。在光学显微镜下，该变形虫在37℃时移动缓慢，但在42℃时不移动。18S rRNA基因以及ITS1 - 5.8S rRNA基因 - ITS2序列的系统发育分析表明，该菌株属于四膜虫属的一个亚分支，其中包括具喙四膜虫、瓦卡马四膜虫和肠四膜虫等。尽管如此，在两个分子系统发育树中，该菌株都与其他物种不同。因此，从独岛分离出的该菌株被提议为一个新物种，即独岛四膜虫，新种。
