@article{mbs:/content/journal/micro/10.1099/00221287-130-2-369, author = "Silva, Manuel T. and Macedo, Paula M.", title = "Ultrastructural Characterization of Normal and Damaged Membranes of Mycobacterium leprae and of Cultivable Mycobacteria", journal= "Microbiology", year = "1984", volume = "130", number = "2", pages = "369-380", doi = "https://doi.org/10.1099/00221287-130-2-369", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-130-2-369", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = " 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 Thiry 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.", }