Submitted to: International Journal of Systematic and Evolutionary Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 12, 1996
Publication Date: N/A
Interpretive Summary: Spiroplasmas are helical, cell wall-less bacteria. They infect plants and insects and are being considered as potential agents for use in biocontrol programs. In order to classify the spiroplasmas, various metabolic tests are used, including one which determines the organism's ability to use the amino acid arginine as an energy source. In the current study, we conducted a comprehensive examination of arginine usage by 21 spiroplasmas, including 7 which represent a new species. We found that a previous report of arginine used by 2 spiroplasmas (subgroups I-5 and I-6) was in error, and we hereby amend it. Although other workers have reported that addition of sugar to growth media may be necessary for the utilization of arginine, the presence of sugar tended to obscure arginine use in our studies. This information will be of interest to microbiologists who are attempting to classify spiroplasmas or to determine their nutrient and energy needs.
Hydrolysis of arginine is a classical diagnostic test for species in the mollicute order Entomoplasmatales. We now report data for arginine utilization by spiroplasmas, as determined by standard methods. In addition, modified methods were developed for fastidious spiroplasmas such as strain LD-1T, the Colorado potato beetle spiroplasma. Twenty-one spiroplasma strains, representing 13 existing groups or subgroups, and eight ungrouped spiroplasmas (seven of which represent putative groups) were studied. Arginine reactions of eight strains were as previously reported, but previously reported positive tests for spiroplasma subgroups I-5 and I-6 (Spiroplasma insolitum) could not be repeated, and are corrected herein. Although other workers have reported that addition of carbohydrate to media may be necessary for the utilization of arginine, the presence of glucose tended to obscure arginine hydrolysis in our studies.