Yangon Technological University, Pharmaceutical Research Department, Myanma Scientific and Technological Research Department, Ministry of Science and Technology, Yangon, Myanmar.
Department of Parasitology, Tokai University School of Medicine, Isehara, Kanagawa 259-1193, Japan; Department of Medical Microbiology and Parasitology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China.
Infect Genet Evol. 2021 Aug;92:104830. doi: 10.1016/j.meegid.2021.104830. Epub 2021 Mar 30.
Entamoeba nuttalli found in macaques is phylogenetically the closest species to Entamoeba histolytica and is potentially pathogenic. In this study, the prevalence of Entamoeba infections was examined in wild rhesus macaques by examining 73 and 90 fecal samples collected from two sites, Popa Taung Kalat (PTK) and Pho Win Taung (PWT), in Myanmar. The positive rates of E. nuttalli detected using PCR were 49% and 31% in PTK and PWT, respectively, but no infections of E. histolytica and E. moshkovskii were found. Entamoeba dispar was detected in 6% of samples only from PWT. Positive rates of E. chattoni and E. coli were both 70% in PWT and 67% and 79% in PTK, respectively. Six E. nuttalli strains from PTK and eight from PWT were obtained in the culture with xenic medium and then, one and two strains, respectively, were axenized and finally cloned. The genotypic analysis of serine-rich protein genes revealed two genotypes each in both sites. The genotypes found in five of six strains from PTK were similar to those from the strains found in Nepal, whereas the remaining one from PTK and two from PWT were similar to those obtained from macaques in China. The sequence of the 18S rDNA of strains with these four genotypes was identical to that of the strains from China. Six loci of tRNA-linked short tandem repeats were analyzed for further genotyping of the strains. Although there were two types in locus A-L in PTK isolates, one of each type for PTK and PWT was found in the other loci, including locus A-L in PWT strains. These results demonstrated that the E. nuttalli strains from Myanmar are closer to the strains from macaques in China rather than those from macaques in Nepal.
在猕猴中发现的纳氏内阿米巴在系统发育上与溶组织内阿米巴最为接近，具有潜在的致病性。本研究通过检查来自缅甸两个地点帕奥塔通卡拉特（PTK）和波温塔通（PWT）的 73 和 90 份粪便样本，检查了野生恒河猴中的内阿米巴感染流行情况。PCR 检测到的纳氏内阿米巴阳性率分别为 PTK 为 49%，PWT 为 31%，但未发现溶组织内阿米巴和莫氏内阿米巴感染。仅在 PWT 中发现 6%的样本存在迪斯帕内阿米巴。在 PWT 中，查氏内阿米巴和大肠杆菌的阳性率均为 70%，而在 PTK 中，阳性率分别为 67%和 79%。从 PTK 获得了 6 株纳氏内阿米巴和从 PWT 获得了 8 株纳氏内阿米巴，然后分别对 1 株和 2 株进行了无共生体培养，最终克隆。丝氨酸丰富蛋白基因的基因型分析显示，两个地点均各有两种基因型。来自 PTK 的 6 株中的 5 株与来自尼泊尔的菌株相似，而剩余的一株来自 PTK，两株来自 PWT，与来自中国的猕猴相似。这四种基因型的菌株 18S rDNA 序列与来自中国的菌株相同。对 6 个 tRNA 连接的短串联重复序列位点进行了分析，以进一步对菌株进行基因分型。尽管在 PTK 分离株的 A-L 位点有两种类型，但在其他位点，包括 PWT 分离株的 A-L 位点，发现了每种类型的一个。这些结果表明，来自缅甸的纳氏内阿米巴株与来自中国猕猴的株更为接近，而与来自尼泊尔猕猴的株则不同。
