@article{mbs:/content/journal/micro/10.1099/00221287-134-7-2029, author = "Gabriel, Miroslav and Kopecká, Marie", title = "Studies on Cell Division in Regenerating Protoplasts of the Yeast Schizosaccharomyces japonicus", journal= "Microbiology", year = "1988", volume = "134", number = "7", pages = "2029-2037", doi = "https://doi.org/10.1099/00221287-134-7-2029", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-134-7-2029", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "Regeneration of the cell wall in yeast protoplasts can be blocked by the action of snail enzymes. Electron microscopic studies of protoplasts of Schizosaccharomyces japonicus var. versatilis showed that incubation in the presence of snail enzymes resulted in the production of incomplete cell walls consisting of α-(1 → 3)-glucan microfibrils aggregated into flat sheets of irregular size. This incomplete cell wall did not allow the formation of a septum and subsequent cell division. In contrast, protoplasts of the same yeast species growing in a flattened state produced by physical constraint formed incomplete walls that permitted cytokinesis but not reversion of the protoplasts to normal cells. These incomplete walls comprised three structural components: (i) a continuous network of long β-(1 →3)-glucan microfibrils; (ii) short α-(1 →3)-glucan microfibrils; and (iii) an amorphous matrix. This ultrastructural picture corresponded to the first stages of regeneration (reached after 2–3 h incubation) leading to a complete cell wall; the walls in the flattened protoplasts, however, were not completed and consequently the protoplasts did not revert to normal cells.", }