Fig. 3. Growth defects in the ltpA mutant.

WT, LtpA-mut, and LtpA-com strains were cultured in standard BSK-II medium at 37 °C (a) or 23 °C (b). The initial cell densities for the cultures at 37 °C and 23 °C were 10³ spirochetes/ml and 10⁵ spirochetes/ml, respectively. Numbers of spirochetes were enumerated daily using dark-field microscopy. Each data point is derived from the average of the data from three independent cultures. Statistical significance was calculated between LtpA-mut and the WT group. *P < 0.05