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The pathogenicity of the purified hyphae of Filobasidiella neoformans was determined. The hyphal particles were inoculated into white Swiss female mice via the intracranial and intravenous route. Upon autopsy, infection was seen with as few as 25 hyphal elements. The brain, liver, and spleen were examined culturally and the brain examined histologically to prove the pathogenicity of the purified hyphae. 相似文献
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Light microscopy of basidia, basidiospores, and nuclei in spores and hyphae of Filobasidiella neoformans (Cryptococcus neoformans). 总被引:4,自引:1,他引:3 下载免费PDF全文
K H Erke 《Journal of bacteriology》1976,128(1):445-455
Three hypha-forming strains of Cryptococcus neoformans were induced to form basidia and basidiospores. Light microscopy showed that basidia formed at the ends of terminal hyphal cells and were able to produce from a few to many basidiospores. The morphology of the sexual structures indicated that these strains belonged to the recently described perfect state of C. neoformans, Filobasidiella neoformans. The average dimensions of the basidiospores were 1.9 mum in width by 2.7 mum in length. Giemsa staining revealed that dikaryotic cells were formed in all three strains. Only one strain had both terminal and subterminal dikaryons, indicating functional clamp connections, whereas the two remaining strains had dikaryons restricted to the terminal cells. Basidiospores of two strains were mononucleate, and yeast cell clones derived from single basidiospores of these two strains were able to complete the sexual life cycle, thus indicating their primary homothallic nature. 相似文献
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The chronology of Phomopsis ganjae conidia germination and infection of Cannabis sativa leaves was observed with the scanning electron microscope. A-conidia germination approached 100% after 24 h, appresoria initiation began after 36 h; B-conidia germinated by 52 h but were not infective. Four-week-old C. sativa seedlings were more susceptible than 16-week-old plants, males more than females. THC and CBD, extracted and separated via TLC, inhibited P. ganjae conidia germination and hyphal growth. 相似文献
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In the sexual phase of Cryptococcus neoformans four post-meiotic nuclei give rise to the nuclei of four long chains of basidiospores. If there is a fixed relationship between one post-meiotic nucleus and one chain the result should be genetic homogeneity within single chains; random composition of chains would represent the opposite case. We tested for homogeneity in single chains from crosses of niacin-auxotrophs to the wild type by dissecting single chains of basidiospores from mature fruiting bodies. Out of 14 chains, 11 were homogeneous; the probability of obtaining this result by random processes was <0.01. These results suggest that mitotic products of a particular post-meiotic nucleus may be channeled into a particular basidiospore chain. 相似文献
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To construct a genetic linkage map of the heterothallic yeast, Cryptococcus neoformans (Filobasidiella neoformans), we crossed two mating-compatible strains and analyzed 94 progeny for the segregation of 301 polymorphic markers, consisting of 228 restriction site polymorphisms, 63 microsatellites, two indels, and eight mating-type (MAT)-associated markers. All but six markers showed no significant (P < 0.05) segregation distortion. At a minimum LOD score of 6.0 and a maximum recombination frequency of 0.30, 20 linkage groups were resolved, resulting in a map length of approximately 1500 cM. Average marker density is 5.4 cM (range 1-28.7 cM). Hybridization of selected markers to blots of electrophoretic karyotypes unambiguously assigned all linkage groups to chromosomes and led us to conclude that the C. neoformans genome is approximately 20.2 Mb, comprising 14 chromosomes ranging in size from 0.8 to 2.3 Mb, with a ratio of approximately 13.2 kb/cM averaged across the genome. However, only 2 of 12 ungrouped markers hybridized to chromosome 10. The hybridizations revealed at least one possible reciprocal translocation involving chromosomes 8, 9, and 12. This map has been critical to genome sequence assembly and will be essential for future studies of quantitative trait inheritance. 相似文献
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Ultrastructure of septal complex in Filobasidiella neoformans (Cryptococcus neoformans). 总被引:2,自引:2,他引:0 下载免费PDF全文
Electron microscopy of Filobasidiella neoformans, the perfect state of Cryptococcus neoformans, revealed basidiomycete doliporesepta between hyphal cells and also between clamp connections and adjacent cells. The pore-occluding material was a heterogeneous flattened plate with dark margins and a lighter center, as seen in the species of Filobasidium. Representative basidiomycete parenthesomes were lacking, and endoplasmic reticulum was seen in the dolipore region. 相似文献
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Filobasidiella neoformans, the teleomorph of Cryptococcus neoformans, was observed using electron microscopy to confirm its phyletic status. No septa were found in the basidium of F. neoformans. Mature basidiospores were encapsulated by a relatively thick cell wall. Basidiospores directly budded from the basidium without sterigma formation, and no hilar appendix was noted. A lateral component of a synaptonemal complex was observed. As for mitotic apparatus, a spherical nucleus associated organelle (NAO), 0.12 m in diameter, was found in the hemispherical depressive area of the nuclear envelope. Therefore, this fungus seems to have both characteristics of the Holobasidiomycetidae and of the primitive Basidiomycotina such as the Teliomycetes. 相似文献
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The taxonomic status of Filobasidiella arachnophila Malloch et al. was investigated. The carbohydrate profile of two strains revealed basidiomycetous affinities. However, the vast majority of the mycelial cells are monokaryotic, demonstrating that F. arachnophila is not a typical basidiomycete. The morphological resemblance to the two teleomorph species of Filobasidiella is noteworthy and therefore the accommodation in Filobasidiella is maintained. F. arachnophila proved to be identical with Aspergillus depauperatus Petch and the new combination Filobasidiella arachnophila (Petch) Samson et al. is made. 相似文献
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M Deminatti J L La? X Desbiens N Jacqueloot 《Comptes rendus des séances de la Société de biologie et de ses filiales》1975,169(4):981-986
Metaphase chromosomes were isolated from KB cells according to Salzman and Mendelsohn's method. Whole-mount electronic microscopic preparations of chromosomes in situ, after isolation and after purification showed that the morphological patterns of this material are preserved in spite of physical and chemical treatments (pH 3). 相似文献
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A sensitive and diagnostically applicable conjugate for the rapid and accurate detection and identification of Cryptococcus neoformans has been developed. C. neoformans rabbit antisera were produced by 14 daily intravenous injections of 36 million cells for a total dosage of approximately 500 million cells. Cross-staining reactions with species of Cryptococcus other than C. neoformans, as well as with Candida species, were eliminated by adsorption of the C. neoformans conjugate with cells of C. diffluens and C. krusei. 相似文献
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Four media, Staib's Guizotia abyssinica, trypan blue, and Staib's with 2 and 10 mg of methyl violet per liter, were compared for the selective and differential isolation of Cryptococcus neoformans from environmental samples. Trypan blue medium allowed for the differentiation of C. neoformans colonies from Candida albicans colonies several days earlier than did Staib's medium. The addition of methyl violet to Staib's medium was found to be inhibitory to some strains of all species tested. Diphenyl in Staib's medium inhibited the growth of 30 strains of C. neoformans and C. albicans. 相似文献
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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 m in length, composed of bundles of 6.7–8.0 nm wide filaments were observed in both FS and CF hyphae. 相似文献
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Apical organization in the somatic hyphae of fungi 总被引:8,自引:0,他引:8