FIG. 6.

Determination of polyP levels in Leishmania strains. (A) Representative emission spectra of polyP-bound DAPI in L. donovani dd8 (continuous line) and L. donovani L82 (dashed line) after sample excitation at 415 nm. Parasites were incubated for 10 min with 10 μg/ml DAPI as described in Materials and Methods. (B) PolyP levels in different Leishmania strains were determined by spectral integration from 450 to 650 nm as described above and compared with those in L. donovani dd8. Values for L. donovani L82 versus those for L. donovani dd8 and L. tropica k27 were significantly different (P < 0.004 and P < 0.0001, respectively), using Student's t test. Results represent means ± standard deviations of four independent experiments. a. u., arbitrary units.