【作者】 刘家英； 吴利红；

【Author】 Liu Jiaying Wu Lihong (Department of Biology, East China Normal University, Shanghai 200062)

【机构】 华东师范大学生物学系；

【摘要】 对两个棘阿米巴角膜炎病原体中国分离株(L和W)以及Acanthamoeba lugdunen- sis(ATCC 50241)和A．quina(ATCC 50241)的线粒体DNA(mtDNA)进行了限制性内切酶分析。用六种不同的限制性内切酶(Bgl Ⅱ、EcoRⅠ、HindⅢ、BanHⅠ、SalⅠ和KpnⅠ) 对这四个虫株进行酶解和电泳后,分别获得24、24、23与23条可见区带,酶切片段大小范围为2,100-23,000bp,共有三种不同的酶切图谱,其中,L和W株的酶切图谱完全相同。虫株间共享酶切片段数据分析显示,L和W株的相似系数为1;L／W与A．lugdunensis和A． quina的遗传距离(P值)分别为8．21和5．80,A．lugdunensis和A．quina的P值为7．23。结合我们实验室对L／W株的形态学特征观察、致病性试验、同工酶电泳比较以及随机扩增多态性DNA分析的结果,我们进一步确认L和W这两个分离株属同一棘阿米巴虫种,A． lugdunensis-quina。更多还原

【Abstract】 Two pathogenic strains of Acanthamoeba (L and W) were isolated from the keratitis patients wearing soft contact lens in China. Based on their morphological features, pathogenicity and isoenzyme, both isolates were preliminarily identified as A. lugdunensis - quina Restriction endonuclease analysis was undertaken in order to characerize the pathogenic free - living amoebae at moleculat level further. Methods; Four Acanthamoeba strains including W, L, A, lugdunensis (ATCC 50240)and A. quina (ATCC 50241 )were examined in the present work. The extracted mtDNAs were digested with six restriction enzymes (Bgl II , EcoR I , Hind III , BamH I, Sal I, and Kpn I )respectively. Based on the electrophoretic patterns, the similarity coefficient (F value)and genetic distance (P value)between the strains were calculated. Results: We have further demonstrated that the two Chinese isolates.should be considered as the same species of genus Acanthamoeba according to their sharing a single phenotype by comparison of the mtDNA -RELPs band patterns. Both of the Chinese pathogens seemed genetically related to A. lugdunensis-A. quina. Conclusion: The first direct connection more closectionbe-tween human disease and A. lugdunensis - A. quina was reported from the two Chinese cases of acanthamoeba keratitis. The molecular evidences obtained from the present and previous studies of mtDNA - RFLPs and genome RAPDs further comfirmed the phylogenetic relationships between some closely related strains belonging to Group II of genus Acanthamoeba .更多还原