Sato Hiroshi, Takano Ai, Kawabata Hiroki, Une Yumi, Watanabe Haruo, Mukhtar Maowia M
Laboratory of Veterinary Parasitology, Faculty of Agriculture, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.
J Parasitol. 2009 Aug;95(4):1029-33. doi: 10.1645/GE-1816.1.
Peripheral blood from a ball python (Python reginus) imported from Ghana was cultured in Barbour-Stoenner-Kelly (BSK) medium for Borrelia spp. isolation, resulting in the prominent appearance of free, and clusters of, trypanosomes in a variety of morphological forms. The molecular phylogenetic characterization of these cultured trypanosomes, using the small subunit rDNA, indicated that this python was infected with a species closely related to Trypanosoma varani Wenyon, 1908, originally described in the Nile monitor lizard (Varanus niloticus) from Sudan. Furthermore, nucleotide sequences of glycosomal glyceraldehyde-3-phosphate dehydrogenase gene of both isolates showed few differences. Giemsa-stained blood smears, prepared from the infected python 8 mo after the initial observation of trypanosomes in hemoculture, contained trypomastigotes with a broad body and a short, free flagellum; these most closely resembled the original description of T. varani, or T. voltariae Macfie, 1919 recorded in a black-necked spitting cobra (Naja nigricollis) from Ghana. It is highly possible that lizards and snakes could naturally share an identical trypanosome species. Alternatively, lizards and snakes in the same region might have closely related, but distinct, Trypanosoma species as a result of sympatric speciation. From multiple viewpoints, including molecular phylogenetic analyses, reappraisal of trypanosome species from a wide range of reptiles in Africa is needed to clarify the relationship of recorded species, or to unmask unrecorded species.
对一条从加纳进口的球蟒(Python reginus)的外周血进行培养,将其置于用于疏螺旋体属分离的巴伯-斯托纳-凯利(BSK)培养基中,结果出现了形态各异的游离及成簇的锥虫。利用小亚基核糖体DNA对这些培养的锥虫进行分子系统发育特征分析,结果表明这条蟒蛇感染了一种与1908年在苏丹尼罗河巨蜥(Varanus niloticus)中首次描述的瓦氏锥虫(Trypanosoma varani Wenyon)密切相关的物种。此外,两种分离株的糖体甘油醛-3-磷酸脱氢酶基因的核苷酸序列差异不大。在血液培养中首次观察到锥虫8个月后,从感染的蟒蛇制备的吉姆萨染色血涂片含有宽体和短游离鞭毛的动基体;这些与瓦氏锥虫的原始描述最为相似,或与1919年在来自加纳的黑颈喷毒眼镜蛇(Naja nigricollis)中记录的伏氏锥虫(T. voltariae Macfie)最为相似。蜥蜴和蛇很有可能自然地共享同一锥虫物种。或者,同一地区的蜥蜴和蛇可能由于同域物种形成而拥有密切相关但不同的锥虫物种。从多个角度来看,包括分子系统发育分析,需要对非洲多种爬行动物的锥虫物种进行重新评估,以阐明已记录物种之间的关系,或发现未记录的物种。