SPIROPLASMA-LINEOLAE SP. NOV., FROM THE HORSEFLY TABANUS LINEOLA (DIPTERA, TABANIDAE)

Spiroplasma strain TALS-2(T) from the viscera of the striped horsefly, Tabanus lineola, collected in Georgia was serologically distinct from other Spiroplasma species, groups, putative groups, and subgoups. Lig ht and electron microscopy of cells of strain TALS-2(T) revealed helic al motile cells surrounded only by a single cytoplasmic membrane, The organism grew in M1D and SP-4 liquid media, Growth also occurred in 1% serum fraction medium and in conventional horse serum medium, Growth in liquid media was serum dependent. The strain passed through 220-nm filter poles, but was retained in filters with 100-nm pores. The optim um temperature for growth was 30 degrees C. Multiplication occurred at temperatures from 20 to 37 degrees C, with a doubling time at the opt imum temperature of 5.6 h in M1D broth, Strain TALS-2(T) catabolized g lucose but hydrolyzed neither arginine nor urea. The guanine-plus-cyto sine content of the DNA was 25 +/- 1 mol%. The genome size was 1,390 k bp. Six isolates serologically similar to strain TAS-2(T) were obtaine d from the same host in coastal Georgia. Three strains closely related to strain TALS-2(T) were isolated from the horsefly Poeciloderas quad ripunctatus in Costa Rica, Strain TALS-2(T) (= ATCC 51749), a represen tative of group XXVII, is designated the type strain of a new species, Spiroplasma lineolae (Mollicutes: Entomoplasmatales).