Purine Analogue Sensitivity and Lipase Activity of Leptospires

Abstract

The genus Leptospira can be divided into three groups based on purine analogue sensitivity and lipase (trioleinase) activity. Group 1 contains members of the "parasitic complex" of leptospires which initially cannot grow in media containing 10 ,ug of 2,6-diaminopurine (DAP) per ml or 200 ,ug of 8-azaguanine per ml. In addition, leptospires in this group possess lipase activity. Group 2 also contains members of the "parasitic complex" of leptospires. Although these leptospires are similarly sensitive to 8-azaguanine, they differ from group 1 leptospires in that they grow in media containing 10 ,ug of DAP per ml, and they do not possess detectable lipase activity. Group 3 consists of leptospires belonging to the "biflexa complex." These leptospires are resistant to both purine analogues and have lipase activity.

Sensitivity of pathogenic and free-living Leptospira spp. to UV radiation and mitomycin C

“…A number of phenotypic characteristics are used to differentiate L. interrogans from L. biflexa. L. biflexa is more resistant than L. interrogans to copper sulfate (13), 8-azaguanine (31), and 2,6-diaminopurine (30). L. biflexa can also grow at lower temperatures (29) and is more likely to produce lipase (30).…”

Characterization of Leptospires according to Fatty Acid Requirements

“…In contrast, the parasitic leptospires depend upon the types of fatty acids available in the mammalian host, namely the long chain saturated and unsaturated fatty acids, and they do not grow well at the low temperatures. Serotypes such as ballum, which are lipase (trioleinase) negative (Johnson & Harris, 1968), having a relatively high requirement for unsaturated fatty acids and not producing a severe disease in mammals, are probably older, well-adapted parasites. Serotypes such as canicolu, which possess lipase activity, having a lesser requirement for unsaturated fatty acids and producing a more severe disease, may be parasites of more recent origin.…”

Antileptospiral activity in lower-vertebrate sera

“…Serotypes of the biflexa complex include patoc Patoc I, semaranga Veldrat Semarang 173, biflexa CDC, and sao-paulo Sao Paulo. Each of the leptospires has been characterized as a member of the biflexa complex by standard procedures such as 8-azaguanine resistance (17), growth at low temperature (11), mammalian serum sensitivity (15), CuSO4 resistance (8), lipase production, and 2,6-diamino purine resistance (12). The serotypes of the parasitic complex used in this study include canicola Hond Utrecht IV, arboreae Arborea, ballum Mus 127, pomona Pomona, and grippotyphosa Mal 1540.…”

“…VOL. 12,1975 on July 16, 2020 by guest http://iai.asm.org/ Downloaded from activity after Ca2+ reactivation on the homologous or heterologous serotype. In some experiments the absorbed serum lost activity towards the homologous but not the heterologous serotype tested.…”