Comparative Analysis of the Ribosomal Componentsof the Hydrogenosome-Containing Protist, Trichomonas vaginalis
Comparative Analysis of the Ribosomal Componentsof the Hydrogenosome-Containing Protist, Trichomonas vaginalis
复制标题
DOI：
10.1007/s00239-004-2604-0
复制
发表时间：
2004-07
影响因子：
3.9
通讯作者：
N. Arisue;Yasushi Maki;Hideji Yoshida;A. Wada;L. Sánchez;Miklós Müller;T. Hashimoto
中科院分区：
文献类型：
--
作者：
N. Arisue;Yasushi Maki;Hideji Yoshida;A. Wada;L. Sánchez;Miklós Müller;T. Hashimoto
无线粒体但含氢酶体的原生生物谱系（毛滴虫）的核糖体先前已被报道为原核生物或原始真核生物，基于证据表明它们具有70 S沉降系数和少量蛋白质，与原核生物核糖体相似。为了确定毛滴虫核糖体的组分是否确实不同于典型的真核核糖体的组分，表征了代表性的毛滴虫（Trichomonasvagulovirus）的核糖体。T.阴道菌核糖体比酵母菌小，比大肠杆菌大。基于二维PAGE分析，不同的核糖体蛋白的数量估计为约80。这一数目与典型真核生物的相同（约80个），但大于E。大肠杆菌（约55）。对18个蛋白点进行N-末端氨基酸序列测定，并对4个核糖体蛋白基因进行全序列测定，结果显示这些蛋白具有典型的真核生物特征。对目前可用的五种核糖体蛋白的系统发育分析也清楚地证实了T. vaginalissequences位于真核进化枝内。比较了T. vaginalis与其他真核生物的结果表明，在典型的真核生物中常见的所有螺旋都存在并保守在T. vaginalis中，而可变区缩短或丢失。这些证据表明，T。vaginalisribosome没有原核或原始真核生物的特征，但显然是典型的真核生物类型。
The ribosomes of the amitochondriate but hydrogenosome-containing protist lineage, the trichomonads, have previously been reported to be prokaryotic or primitive eukaryotic, based on evidence that they have a 70S sedimentation coefficient and a small number of proteins, similar to prokaryotic ribosomes. In order to determine whether the components of the trichomonad ribosome indeed differ from those of typical eukaryotic ribosomes, the ribosome of a representative trichomonad,Trichomonas vaginalis, was characterized. The sedimentation coefficient of theT. vaginalisribosome was smaller than that ofSaccharomyces cerevisiaeand larger than that ofEscherichia coli. Based on two-dimensional PAGE analysis, the number of different ribosomal proteins was estimated to be approximately 80. This number is the same as those obtained for typical eukaryotes (approximately 80) but larger than that ofE. coli(approximately 55). N-Terminal amino acid sequencing of 18 protein spots and the complete sequences of 4 ribosomal proteins as deduced from their genes revealed these sequences to display typical eukaryotic features. Phylogenetic analyses of the five ribosomal proteins currently available also clearly confirmed that theT. vaginalissequences are positioned within a eukaryotic clade. Comparison of deduced secondary structure models of the small and large subunit rRNAs ofT. vaginaliswith those of other eukaryotes revealed that all helices commonly found in typical eukaryotes are present and conserved inT. vaginalis, while variable regions are shortened or lost. These lines of evidence demonstrate that theT. vaginalisribosome has no prokaryotic or primitive eukaryotic features but is clearly a typical eukaryotic type.