Presence of putative sphingomyelinase genes among members of the family Leptospiraceae

Abstract

The presence of multiple DNA elements in pathogenic members of the family Leptospiraceae, similar to the sphA sphingomyelinase gene from Leptospira borgpetersenii, was demonstrated by low-stringency hybridization experiments. These DNA elements were designated putative sphingomyelinase genes. Grouping of strains by similarity of hybridization patterns corresponds to the species subdivision of the family Leptospiraceae on the basis of genetic characteristics. Therefore, hybridization with the sphA gene can be used as a taxonomic tool. These hybridization experiments indicate the presence of two groups of genetically related pathogenic Leptospira species.

Characterization of Leptospira isolates from serovar hardjo by ribotyping, arbitrarily primed PCR, and mapped restriction site polymorphisms

“…Differences in the pathogenicities of the two groups have been suggested (23), and the epidemiology of hardjobovis infections is variable, depending on the geographical region from which the strains are derived (42). The delineation of these two groups was confirmed by studying antigenic structures (21) and by using recombinant probes (20,30,33).…”

“…Other genetic typing methods have proved to be of value and serve as supplementary or alternative typing systems, particularly in epidemiological studies, since they identify strain differences at the subserovar level. These include restriction enzyme analysis (REA) of chromosomal DNA by fixedfield gel electrophoresis (6,22,31,32) or pulsed-field gel electrophoresis (PFGE) (15, 16), the use of recombinant DNA probes (20,30,33,41), and ribotyping (24,25).…”

Análise das proteínas de Leptospira com possível papel hemolítico através de expressão recombinante: detecção de expressão nativa, atividade biológica e potencial vacinal

“…Nesse caso, são encontradas freqüentemente em patógenos, atuando como toxinas (HEINZ et al 1998;RODRIGUES-LIMA et al 2000). De fato, em Leptospira, os genes que codificam para esfingomielinases são encontrados somente em linhagens patogênicas (SEGERS et al 1992), embora tal fato não ocorra com os genes que codificam as outras hemolisinas (LOUVEL et al 2006;PICARDEAU et al 2008). É de se notar que as leptospiras patogênicas possuem múltiplos genes que codificam para esfingomielinases, alcançando um total de cinco genes em L.…”

Genetic variability and expression of sphA and sphB genes and immunogenicity of SphA and SphB of Leptospira borgpetersenii serovar hardjo

“…Others, however, have reported cytopathic acti\ity in association with both virulent and saprophytic leptospires (58,149,151). (126). These studies led to the discovery of an additional related gene in type hardjo-bovis (127) and four other related genes in L.…”

“…inadai does not contain regions that hybridize with sphA, while among saprophytes, only a single isolate of L. meyeri demonstrates hybridization with this gene (126)(127)(128).…”