01833nas a2200313   4500000000100000008004100001260001300042653001200055653001500067653001800082653001700100653001100117653001200128653000900140653002500149653001800174653002500192653003100217653003100248653003400279653000900313100001400322700001500336245012500351300001100476490000800487520101000495022001401505       1984                            d  c1984 Feb10aAnimals10aArmadillos10aCell Membrane10aDensitometry10aHumans10aleprosy10aMice10aMicroscopy, Electron10aMycobacterium10aMycobacterium leprae10aMycobacterium lepraemurium10aMycobacterium tuberculosis10aPeriodic Acid-Schiff Reaction10aRats1 aSilva M T1 aMacedo P M00aUltrastructural characterization of normal and damaged membranes of Mycobacterium leprae and of cultivable mycobacteria.  a369-800 v1303 a<p>Microdensitometry showed that the membrane profiles of normal cultivable mycobacteria were very asymmetric (outer layer denser and thicker than the inner layer), while the profiles of normal-looking M. leprae in lepromatous patients, in experimentally infected armadillos and in nude mice were approximately symmetric; moreover, the membrane of M. leprae was thicker than that of cultivable species. Using two cytochemical methods for the ultrastructural detection of periodic acid-Schiff (PAS)-positive molecules (the Thiéry procedure, and staining with phosphotungstic acid at low pH) we found that the membrane of cultivable mycobacteria, growing in vitro or in vivo, had PAS-positive components exclusively in the outer layer, while the normal-looking M. leprae in patients and in armadillos had membranes with PAS-positive components in both layers. The membranes of damaged cultivable mycobacteria, in vivo or in vitro, and of damaged M. leprae, in patients or armadillos, were PAS-negative.</p>  a0022-1287