Attias Márcia, Sato Lyslaine H, Ferreira Robson C, Takata Carmen S A, Campaner Marta, Camargo Erney P, Teixeira Marta M G, de Souza Wanderley
Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagens, Rio de Janeiro, Brazil.
J Eukaryot Microbiol. 2016 Sep;63(5):610-22. doi: 10.1111/jeu.12310. Epub 2016 Mar 24.
We described the phylogenetic affiliation, development in cultures and ultrastructural features of a trypanosome of Leptodacylus chaquensis from the Pantanal biome of Brazil. In the inferred phylogeny, this trypanosome nested into the Anura clade of the basal Aquatic clade of Trypanosoma, but was separate from all known species within this clade. This finding enabled us to describe it as Trypanosoma herthameyeri n. sp., which also infects other Leptodacylus species from the Pantanal and Caatinga biomes. Trypanosoma herthameyeri multiplies as small rounded forms clumped together and evolving into multiple-fission forms and rosettes of epimastigotes released as long forms with long flagella; scarce trypomastigotes and glove-like forms are common in stationary-phase cultures. For the first time, a trypanosome from an amphibian was observed by field emission scanning electron microscopy, revealing a cytostome opening, well-developed flagellar lamella, and many grooves in pumpkin-like forms. Transmission electron microscopy showed highly developed Golgi complexes, relaxed catenation of KDNA, and a rich set of spongiome tubules in a regular parallel arrangement to the flagellar pocket as confirmed by electron tomography. Considering the basal position in the phylogenetic tree, developmental and ultrastructural data of T. herthameyeri are valuable for evolutionary studies of trypanosome architecture and cell biology.
我们描述了来自巴西潘塔纳尔生物群落的查氏细趾蟾（Leptodacylus chaquensis）体内一种锥虫的系统发育归属、培养特性及超微结构特征。在推断的系统发育中，这种锥虫嵌套在锥虫属基部水生类群的无尾目分支中，但与该分支内所有已知物种不同。这一发现使我们能够将其描述为赫氏锥虫（Trypanosoma herthameyeri）新种，它也感染来自潘塔纳尔和卡廷加生物群落的其他细趾蟾物种。赫氏锥虫以小圆形形态聚集繁殖，演变成多分裂形态和副基体的玫瑰花结，释放出带有长鞭毛的长形形态；在稳定期培养物中常见少量的锥鞭毛体和手套状形态。首次通过场发射扫描电子显微镜观察到来自两栖动物的锥虫，揭示了一个胞口开口、发育良好的鞭毛膜以及许多南瓜状形态的凹槽。透射电子显微镜显示高尔基体高度发达、动基体DNA（KDNA）的连环松弛，并且通过电子断层扫描证实有一组丰富的海绵体小管以规则的平行排列方式通向鞭毛袋。考虑到其在系统发育树中的基部位置，赫氏锥虫的发育和超微结构数据对于锥虫结构和细胞生物学的进化研究具有重要价值。
