|Henegar, Roberta - Bobbie|
Submitted to: International Journal of Systematic and Evolutionary Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/14/1998
Publication Date: N/A
Citation: Interpretive Summary: Entomoplasmas are related to mycoplasmas (agents of animal disease) and spiroplasmas (associated with insects and plants). They are non-motile, pleomorphic coccoid, cell wall-less bacteria. All have been isolated from the gut fluid or blood of insects, or from plant surfaces. The current organism, representing the sixth entomoplasma species known, was isolated from the gut of a green tiger beetle. The purpose of the paper is to taxonomically elevate this isolate to a new species. It is named in honor of Eyvind Freundt, a Danish pioneer in the taxonomy of mycoplasmas. Since mollicutes, of which the entomoplasmas are one group, have been shown to be tremendously diverse in number of species and higher level taxa, the entomoplasmas are of interest from the viewpoint of microbial diversity. Since entomoplasmas are associated with insects, they are also potential biocontrol agents for management of pests of agriculture and forest crops.
Technical Abstract: A mollicute (strain BARC 318) isolated from gut tissue of a green tiger beetle (Cicindelidae) was found by dark-field microscopy to consist of non-helical, non-motile, pleomorphic coccoid forms of various sizes. In ultrastructural studies, individual cells varied from 300 to 1200 nm in diameter,were surrounded by a cytoplasmic membrane and showed no evidence of cell wall. The organisms were filterable through membrane filters of pore diameter 200 nm. Optimum growth occurred at 30C, with growth occurring over a temperature range of 15 to 32C. The organism fermented glucose and hydrolyzed arginine but did not hydrolyze urea. BARC 318 was insensitive to 500 U/ml penicillin and required serum or cholesterol for growth. The organism was serologically distinct from all currently described sterol-requiring, fermentative Mycoplasma species, from 12 non-sterol-requiring Mesoplasma species, 13 non-sterol-requiring Acholeplasma species, and from five previously described sterol-requiring Entomoplasma species. Strain BARC 318 was shown to have a DNA base composition (guanine + cytosine) of 34 mol% and a genome size of 870 kbp. The 16S rDNA sequence of strain BARC 318 was compared to 16S rDNA sequences of several other Entomoplasma species and to other representative species in the genus Spiroplasma, genus Mycoplasma, and to other members of the class Mollicutes. These comparisons indicated that BARC 318 had close phylogenetic relationships to other Entomoplasma species. On the basis of these findings and other similarities in morphology, growth and temperature requirements, and genomic