[Progress on classification and identification of Acanthamoeba].

As a pathogenic free-living amoeba, Acanthamoeba is easy to be recognized at the genus level, but difficult to identify at species level on the morphological basis. This review summarizes the methods for Acanthamoeba species classification and identification.

[Sequence analysis of 16S rDNA gene of endosymbiont of Acanthamoeba sp. CB/S1 isolated from soil].

The endosymbiont of Acanthamoeba sp. CB/SI was identified by orcein-carmine staining and 16S rDNA sequence analysis. The endosymbiont bacteria were rod-shaped and darkly stained, and irregularly localized within the cytoplasm. The length of the 16S rDNA was 1534 bp and its DNA sequence was closely related to those of Candidatus Amoebophilus asiaticus and Acanthamoeba sp. KA/E21 with 98% homology. Phylogenetic analysis showed that the endosymbiont of CB/SI, the endosymbiont of KA/E21, Candidatus Amoebophilus asiaticus, the endosymbiont of Ixodes scapularis, and the endosymbiont of Encarsia pergandiella constitute a monophyletic lineage in phylogenetic tree.

[In vitro effect of allitridium on the ultrastructure of Acanthamoeba castellanii].

Acanthamoeba castellanii (T4) was cultured with different concentrations of allitridium for 24 hours, and examined by transmission electron microscope. The results showed that the ultrastructure of Acanthamoeba trophozoites was destroyed gently at concentration of 50 microg/ml allitridium and seriously destroyed under the concentration of 500 microg/ml, indicating that allitridium is effective in destroying Acanthamoeba.

[Genetic identification of Acanthamoeba sp. CJY/S1 and CJY/S2 isolated from soil].

Two isolates of Acanthamoeba sp. CJY/SI and CJY/S2 were received from soil in Yanji of Jilin Province. Full 18S rDNA gene was amplified using PCR, cloned and sequenced. The results were analyzed by software Clustal X. The full length of CJY/S1 and CJY/S2 is 2255 bp and 2252 bp respectively, both belong to T4 genotype.