A riboprinting scheme for identification of unknown Acanthamoeba isolates at species level

Abstract

We describe a riboprinting scheme for identification of unknownAcanthamoeba isolates at the species level. It involved the use of PCR-RFLP of smallsubunit ribosomal RNA gene (riboprint) of 24 reference strains by 4 kinds of restrictionenzymes. Seven strains in morphological group I and III were identified at species levelwith their unique sizes of PCR product and riboprint type by Rsa I. Unique RFCP of 17strains in group II by Dde I, Taq I and Hae III were classified into: (1) four taxa that wereidentifiable at the species level, (2) a subgroup of 4 taxa and a pair of 2 taxa that wereidentical with each other, and (3) a species complex of 7 taxa assigned to A. castellaniicomplex that were closely related. These results were consistent with those obtained by18s rDNA sequence analysis. This approach provides an alternative to the rDNAsequencing for rapid identification of a new clinical isolate or a large number ofenvironmental isolates of Acanthamoeba .