Comparative study on the thin-layer chromatographic pattern of methyl mycolates of M. leprae and related species

The thin-layer chromatographic (TLC) pattern of methyl mycolates of Mycobacterium leprae has been compared with the lipids extracted from M. leprae-infected tissue material and also with those of other cultivable mycobacterial species. It has been found that M. leprae-derived methyl mycolates give two spots, namely, alpha- and keto-derivatives, after charring the TLC plates with K2Cr2O7/H2SO4 spray. Lipids extracted from infected tissue material also show spots with the same Rf values when compared with those of armadillo-derived M. leprae. Normal skin tissue extracts, however, do not show any presence of mycolates. This TLC pattern of M. leprae-derived methyl mycolates is characteristic and is not shown by any other mycobacterial species isolated from leprosy lesions. The strain and species which have been earlier found to resemble M. leprae antigenically or biochemically could readily be distinguished with the help of the TLC pattern of their methyl mycolates.