Application of an easy and reliable method for sulfolipid-I detection in the study of its distribution in Mycobacterium tuberculosis strains

Sulfolipid-I (SL-I) is a specific Mycobacterium tuberculosis glycolipid tha t has been involved in the mechanisms of tuberculoid infection. Until now, a limited number of M. tuberculosis strains have been studied to ascertain their SL-I content, mainly due to the laborious techniques of purification used: DEAE-cellulose column chromatography (DEAE) or extensive solvent extr actions. We designed a two-dimensional thin layer chromatographic (2D-TLC) system which allows the easy and reliable detection of SL-I in small amount s of M. tuberculosis-free glycolipid extracts without previous purification . A characteristic SL-I signal was clearly identified by a differential cre syl violet metachromatic stain. Seven clinical isolates, M. turberculosis H 37Ra, H(37)Rv and Canetti strains were tested by DEAE and the 2D-TLC system . Identical results were found using both methodologies. The 2D-TLC methodo logy devised could be applied to a large number of strains to ascertain eas ily the distribution of SL-I in the strains of M. tuberculosis species. (C) 2000 Published by Elsevier Science B.V. All rights reserved.