|Henegar, Roberta - Bobbie|
Submitted to: International Journal of Systematic and Evolutionary Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/1/1996
Publication Date: N/A
Citation: Interpretive Summary: Spiroplasmas (helical wall-less procaryotes) are ubiquitously associated with insects. Some are frank insect pathogens, some transmit plant pathogens, some cause vertically transmitted sex ratio traits. Other species are apparently commensals. The latter group includes some host specialists and species that can invade hemolymph. This genus, because of its immense diversity, has great promise as a source for biocontrol agents. Before any agent can be adapted for biocontrol, its place in the systematics of the genus must be ascertained. In this paper, we describe a spiroplasma species that has been found in firefly beetles and mosquitoes. Because mosquito spiroplasmas have been proposed for biological control of these pests, the results will be of interest to research workers involved in biological control. The work will also be of interest to microbial ecologists and systematists.
Technical Abstract: Spiroplasma strain PUP-1 was isolated from the gut fluid of a firefly beetle Photuris pennsylvanicus in Maryland. Cells of the strain were shown by dark-field microscopy to be helical, motile filaments. Ultrastructural examination by electron microscopy revealed filamentous cells bounded by a single cytoplasmic membrane with no evidence of cell wall. The cells were insensitive to 500 U/ml penicillin and grew in M1D, SP-4, and M-2 broth formulations, as well as in conventional mycoplasma medium under aerobic conditions. Doubling times at 15, 20, 25, and 30C were 83.1, 32.0, 14.9, and 9.8 h, respectively. Suboptimal growth occurred at 37C, and no growth was apparent in cultures maintained at 10 or 40C. The organism required cholesterol for growth and produced acid from glucose, fructose, and trehalose; arginine and urea were not hydrolyzed. The guanine-plus-cytosine content of the deoxyribonucleic acid was 26 ñ 1 mol%, and the genome size was 1375 kbp. These values clearly differentiate strain PUP-1 from the group XXI strain W115, with which it cross-reacts reciprocally at a low level in DF and MI tests. We propose that strain PUP-1 be recognized as the type strain of a new species, Spiroplasma lampyridicola (ATCC 43206).