ISSN:
1615-6102
Keywords:
Basidiomycete
;
Fixation technique
;
Freeze-substitution
;
Fungi
;
Laetisaria arvalis
;
Ultrastructure preservation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary The ultrastructure of freeze-substituted (FS) hyphae ofLaetisaria arvalis is described and compared to that of similar hyphae preserved by conventional chemical fixation (CF). The outline of membrane-bound organelles as well as the plasma membrane was smooth in FS cells. In contrast, hyphae preserved by CF exhibited membrane profiles that were extremely irregular. Centers of presumed Golgi activity were best preserved by FS. Microvesicles, 27–45 nm diameter and hexagonal in transverse section, were observed most readily in FS cells. Filasomes (= microvesicles within a filamentous matrix) were only observed in FS cells. Apical vesicles, 70–120 nm diameter, associated with the centers of Golgi activity and within the Spitzenkörper region exhibited finely granular matrices in FS hyphae, whereas in CF hyphae the contents were coarsely fibrous and less electron-dense. Microvesicles were present at hyphal apices and regions of septa formation. Filasomes were also found at regions of septa formation as well as along lateral hyphal tip cell walls. Microvesicles, but not filasomes, were observed in membrane-bound vesicles (= multivesicular bodies) and in larger vacuoles. Filaments, 5.2–5.4 nm wide, were juxtaposed with centripetally developing septa. Cytoplasmic inclusions, 20–40 μm in length, composed of bundles of 6.7–8.0 nm wide filaments were observed in both FS and CF hyphae.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01276274
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