State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China.
Exp Parasitol. 2012 Feb;130(2):135-40. doi: 10.1016/j.exppara.2011.11.003. Epub 2011 Nov 25.
In the present study, we sequenced the complete mt genome (14,022 bp) of parasitic nematode Contracaecum rudolphii B and its structure and organization compared with Anisakis simplex s.l. The mt genome of C. rudolphii B is slightly longer than that of A. simplex s.l. (13,916 bp). C. rudolphii B mt genome is circular, and consists of 36 genes, including 12 genes for proteins, 2 genes for rRNA and 22 genes for tRNA. This genome contains a high A+T (70.5%) content. The mt gene order for C. rudolphii B is the same as those for A. simplex s.l., but it is distinctly different from other nematodes compared. The start codons inferred in the mt genome of C. rudolphii B are TTG and ATT. Six protein-coding genes use TAA as a stop codon whereas five genes use T and one genes use TAG as a termination codon. This pattern of codon usage reflects the strong bias for A and T in the mt genome of C. rudolphii B. Phylogenetic analyses using concatenated amino acid sequences of the 12 protein-coding genes, with three different computational algorithms (Bayes, ML and MP), all revealed distinct groups with high statistical support, indicating that C. rudolphii B and A. simplex s.l. is distinct but closely related species. These data provide additional novel mtDNA markers for studying the molecular epidemiology and population genetics of the C. rudolphii B, and should have implications for the molecular diagnosis, prevention and control of anisakidosis in humans and animals.
在本研究中，我们对寄生线虫 Contracaecum rudolphii B 的完整线粒体基因组（14022bp）进行了测序，并与 Anisakis simplex s.l. 进行了结构和组织比较。C. rudolphii B 的 mt 基因组比 A. simplex s.l.（13916bp）稍长。C. rudolphii B mt 基因组为圆形，由 36 个基因组成，包括 12 个蛋白基因、2 个 rRNA 基因和 22 个 tRNA 基因。该基因组含有高 A+T（70.5%）含量。C. rudolphii B 的 mt 基因顺序与 A. simplex s.l. 相同，但与其他线虫明显不同。C. rudolphii B mt 基因组中的起始密码子推断为 TTG 和 ATT。六个蛋白编码基因使用 TAA 作为终止密码子，而五个基因使用 T，一个基因使用 TAG 作为终止密码子。这种密码子使用模式反映了 C. rudolphii B mt 基因组中对 A 和 T 的强烈偏好。使用三种不同的计算算法（贝叶斯、最大似然和最大简约）对 12 个蛋白编码基因的氨基酸序列进行联合分析，所有分析都显示出具有高度统计支持的不同分组，表明 C. rudolphii B 和 A. simplex s.l. 是不同但密切相关的物种。这些数据为研究 C. rudolphii B 的分子流行病学和群体遗传学提供了额外的新型 mtDNA 标记，应该对人类和动物的旋毛虫病的分子诊断、预防和控制具有重要意义。
