Comparaison morphologique de 4 souches d'Acanthamoeba du groupe astronyxis‐comandoni

Abstract

RESUME Les trophozoïtes, les noyaux mitotiques et les kystes de 3 souches d'Acanthamoeba comandoni Pussard et d'l souche d'Acanthamoeba astronyxis Ray & Hayes ont été observés sur le vivant pour étudier les caractères morphologiques utilisés pour séparer les 2 espèces (Griffin & Sawyer, 1971). Chez toutes les souches, la centrosphère est visible pendant l'intercinèse comme pendant la mitose. Acanthamoeba astronyxis se distingue des autres souches essentiellement par la forme de la figure nucléaire à la prométaphase. Les caractères de la paroi du kyste ne permettent pas d'opposer nettement Acanthamoeba astronyxis aux autres souches. Les dimensions des trophozoïtes et le diamètre des kystes sont trop variables pour être utilisables en taxonomie. Chez toutes les souches existe une corrélation positive entre la taille du kyste et le nombre des bras de l'enveloppe interne. SYNOPSIS Observations of living trophozoites, mitotic nuclei, and cysts of 3 strains of Acanthamoeba comandoni Pussard and of 1 strain of Acanthamoeba astronyxis Ray & Hayes were made to study the morphologic characters utilized by Griffin & Sawyer (1971) for separating the 2 species. In all 4 strains the centrosphere is visible in the interphase just as during mitosis. A. astronyxis differs from the other strains essentially in the shape of the nuclear pattern in prometaphase. The characteristics of the cyst wall do not permit clear differentiation between the 2 species. Size of the trophozoites and diameter of the cysts are too variable to be utilized for taxonomic purposes. In all 4 strains there is a positive correlation between size of the cyst and the number of rays of its internal layer (endocyst).

Further Observations on the Fine Structure of Acanthamoeba palestinensis (Reich, 1933). The Golgi Complex, Microbodies, and Mitochondria1

“…X40,OOO. in mitosis has been demonstrated i n a few species of Acanthamoeba by phase contrast microscopy and staining techniques (22,26). No electron microscopic studies o f the centrosphere h a v e been made i n dividing cells.…”

Epidemiology of and Genetic Factors Associated with Acanthamoeba Keratitis

“…The classification of Acanthamoeba in 1977 was based on cyst morphology [35]. Using this classification system, at least 31 species of Acanthamoeba were identified, which were broadly divided into three major groups [36].…”

Acanthamoeba Sequence Types and Allelic Variations in Isolates from Clinical and Different Environmental Sources in Italy

“…As recently reviewed [1], morphological approaches were primarily used in classifying species/taxa within the genus. Initially, Acanthamoeba was subdivided into three distinct groups (I-III) [2]. However, the identification of species remained arduous, and the advent of molecular tools, especially methods of analysis based on DNA differences, provided new insights into the relationships between the isolates [3][4][5].…”