Discontinuous genetic variation among mesophilic Naegleria isolates: further evidence that N. gruberi is not a single species.

@article{Robinson1992DiscontinuousGV,
  title={Discontinuous genetic variation among mesophilic Naegleria isolates: further evidence that N. gruberi is not a single species.},
  author={B S Robinson and Peter Christy and Suzanne J. Hayes and Philip J. Dobson},
  journal={The Journal of protozoology},
  year={1992},
  volume={39 6},
  pages={
          702-12
        }
}
Naegleria isolates which are currently placed in the type species N. gruberi display great genetic, physiological and morphological heterogeneity. There are two possible interpretations of the nature of this species--that N. gruberi is a species complex or that it is a single continuously variable species. To distinguish between these alternatives, allelic states were determined for 33 loci in 74 new isolates selected to represent wide geographic sources and diverse temperature limits for… 
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TLDR
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Large genetic heterogeneity within amoebas of the species Naegleria gruberi and evolutionary affinities to the other species of the genus.
The allozyme survey was extended to 7 strains of Naegleria gruberi and N. jadini in order to further characterize the genetic structure of these free-living amoebas. As formerly known for several
A comparative study of 14 strains of Naegleria australiensis demonstrates the existence of a highly virulent subspecies: N. australiensis italica n. spp.
TLDR
Naegleria australiensis does not appear to be as homogenous a species as N. fowleri and seems to be more widespread than previously thought.
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TLDR
The genetic data suggest that there are two main phylogenetic groups in the genus Naegleria, and certain enzymes proved particularly useful from a practical point of view as they allow easy and reliable identification of pathogenic N. fowleri and N. lovaniensis strains.
Genetic structure of populations of Legionella pneumophila.
TLDR
The genetic structure of populations of Legionella pneumophila was defined by an analysis of electrophoretically demonstrable allelic variation at structural genes encoding 22 enzymes in 292 isolates from clinical and environmental sources, showing a heterogeneous array of genotypes that included two previously undescribed species.
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TLDR
A population genetic analysis of extensive data on biochemical polymorphisms indicates that the two fundamental consequences of sexual reproduction are apparently rare or absent in natural populations of the parasitic protozoa.
Starch gel electrophoresis: an effective method for separation of pathogenic and nonpathogenic Naegleria strains.
TLDR
Isoenzyme electrophoresis of 7 different enzyme systems was used to compare 24 strains of Naegleria fowleri and 6 strains of N. gruberi, finding that the 22 pathogenic strains constitute a homogenous species and the remaining nonpathogenic strains could be separated into 2 groups.
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