Morphological studies of N-acetylglucosamine induced germ tube formation by Candida albicans.
In N-acetylglucosamine induced germ tube formation by Candida albicans, multiple (up to five) protuberances appeared within 90 min at 37 degrees C on each yeast cell. The protuberances were extensions of the cytosol and contained vesiclelike structures. Usually only one protuberance subsequently developed into a germ tube. The germ tubes emanated from all aspects of the cell surface but seldom from the budding (long axis) poles. Pseudohyphae, which originated from the budding pole, exhibited a marked constriction at the site of emergence and were 0.6-2.5 microns in diameter compared with a diameter of 0.6-0.8 micron for germ tubes. The presence of septa confirmed that germ tubes are precursors of septate mycelia. Ultrathin-section transmission electron microscopy of aldehyde plus osmium fixed cells revealed electron-lucent walls with a thin electron-dense outer layer. A fibrillar border was also routinely associated with germ tubes. Poststaining with potassium permanganate revealed, in addition, a previously invisible fuzzy layer on the outer region of the cell wall which extended over bud scars and germ tubes and which coalesced at sites of contact between cells.
D000117:Acetylglucosamine / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects / Q000254:growth & development* / Q000648:ultrastructure; D003600:Cytosol / Q000648:ultrastructure; D005614:Freeze Fracturing; D005944:Glucosamine / Q000031:analogs & derivatives*; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D013696:Temperature; D013997:Time Factors
D005944:Glucosamine; D000117:Acetylglucosamine