Figure 1. Influence of the in vitro conditions on native LigA expression by L. interrogans serovar Copenhageni str. Fiocruz L1-130.

The effect of the various combinations of conditions (see Results section) on LigA expression was assessed by rt-PCR. Columns depict the systematic treatments: TS – Temperature upshift from 30°C to 37°C, PO – Physiological osmolarity, Sp – Spermine induction, pH – Urine pH induction. Within each gel the upper and lower bands correspond to the internal PCR control (16S rRNA) and ligA cDNA, respectively (domains 10–12). The lanes contain the amplified cDNA per sample time-point, both pre-treatment (0 h) and post induction (1, 12 and 24 h). Agarose gels were stained with GelRed (Invitrogen). No bands were observed in control samples run without template (data not shown). Samples were standardized according to an OD₄₂₀ 0.25. Data from a representative significant study are shown.