RESUMO
Fatty acid profiles of six leptospira strains representative of genera, species, and serogroups within the family Leptospiraceae were determined by gas liquid chromatography (GLC) of fatty acid methyl ester (FAME) derivatives. The influence of methodological and biological variables on FAME profiles of the same strain was tested. FAME profiles were sharply affected by the fatty acid composition of the culture medium but not by the growth phase. Twenty-four FAME peaks were selected on the basis of their presence in repeated gas chromatographic runs of single strains. Inter-strain divergences of FAME profiles were quantified by linear regression analysis (LR). Step-wise divergences in FAME profiles were observed between strains at serogroup, species, and genus levels.
Assuntos
Ácidos Graxos/análise , Leptospira/análise , Spirochaetaceae/análise , Cromatografia Gasosa , Ésteres , Leptospira/classificação , Leptospira interrogans/análise , Leptospira interrogans/classificação , Leptospira interrogans serovar canicola/análise , Leptospira interrogans serovar canicola/classificação , Análise de Regressão , Spirochaetaceae/classificaçãoRESUMO
Spherical forms of Leptospira interrogans serotype canicola Hond Utrecht IV were induced with 1 m NaCl. Electron micrographs of these salt-altered cells (SAC) revealed that the outer envelope or sheath had pulled away from the protoplasmic cylinder. Treatment of SAC with 0.02% sodium lauryl sulfate solubilized the sheath and released the protoplasmic cylinder. Further processing of the solubilized sheath yielded a pellet which displayed a membrane structure in electron micrographs. The released protoplasmic cylinder showed loss of intracellular organization and the outer envelope present in normal cells. Immunization of hamsters with whole formalized cells, SAC, or sheath in doses as low as 10 mug/animal protected them from death upon challenge with virulent canicola 27.