Distribution and expression of LIC10368 gene in saprophytic and pathogenic leptospires. (A) Genomic DNA from L. biflexa Patoc and from five serovars belonging to the pathogenic species L. interrogans was subjected to PCR analysis with LIC1368 specific primers designed according to L. interrogans serovar Copenhageni genome sequences. The expected size of the PCR product is 540 bp. No DNA was added to the negative control reaction (-). (B) RT-PCR analysis of LIC10368 transcripts in high-passage L. interrogans strains and in the low-passage LO4 (Canicola), Fiocruz L1-130 (Copenhageni), LPF (Pomona) strains. Reactions were performed with the same primer pairs mentioned above. Samples quantity and integrity were verified by amplification of a 1042-bp 16S ribosomal cDNA fragment. RT+: reverse transcriptase present; RT -: reverse transcriptase omitted; M: molecular mass markers.