Skip to main content
PMC home page
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1975 Nov;124(2):959–968. doi: 10.1128/jb.124.2.959-968.1975

Ultrastructural studies of the mycelium-to yeast transformation of Sporothrix schenckii.

R G Garrison, K S Boyd, F Mariat
PMCID: PMC235986  PMID: 1184578

Abstract

Fine details of the internal and external morphology of the in vitro mycelial phase (MP) to yeastlike phase (YP) transition of the dimorphic fungal pathogen Sporothrix schenckii are shown in electron micrographs of ultrathin sections. Morphological transformation at the ultrastructural level was observed to occur by direct formation of budlike structures at the tips and along the hyphae and by oidial cell formation. Direct budding of yeast from conidiospores was not observed. Early transitional forms arising by direct blastic action from the MP possessed conspicuous electron-dense microfibrillar material at the outer limits of the cell wall. The electron density of this microfibrillar material was enhanced by staining with acidified dialyzed iron. It is believed that this extracellular material may be composed in part of an acid mucosubstance. No acid phosphatase activity was associated with this microfibrillar material. This substance was found to be a characteristic of the outer limits of the cell wall of the YP of S. schenckii. Oidial YP cell formation occurred later during the transition. The cell wall of the developing oidial YP transitional form arose from an inner layer of the converting hyphae. No consupicuous alterations of the cytoplasmic content of the parent MP cell was observed during MP-to-YP transition. It is suggested that the MP-to-YP transition of S. schenckii may be regulated by at least two mechanisms involving alterations of the biochemical and/or biophysical nature of the cell wall of the MP cell in response to the conversional stimuli.

Full text

PDF
959

Images in this article

961Image
on p.961
961Image
on p.961
962Image
on p.962
962Image
on p.962
963Image
on p.963
963Image
on p.963
964Image
on p.964
965Image
on p.965
965Image
on p.965
966Image
on p.966

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Carbonell L. M. Cell wall changes during the budding process of Paracoccidioides brasiliensis and Blastomyces dermatitidis. J Bacteriol. 1967 Jul;94(1):213–223. doi: 10.1128/jb.94.1.213-223.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Carbonell L. M., Kanetsuna F., Gil F. Chemical morphology of glucan and chitin in the cell wall of the yeast phase of Paracoccidioides brasiliensis. J Bacteriol. 1970 Feb;101(2):636–642. doi: 10.1128/jb.101.2.636-642.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Carbonell L. M. Ultrastructure of dimorphic transformation in paracoccidioides brasiliensis. J Bacteriol. 1969 Nov;100(2):1076–1082. doi: 10.1128/jb.100.2.1076-1082.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Djaczenko W., Cassone A. Visulization of new ultrastructural components in the cell wall of Candida albicans with fixatives containing TAPO. J Cell Biol. 1972 Jan;52(1):186–190. doi: 10.1083/jcb.52.1.186. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Gilardi G. L. Nutrition of systemic and subcutaneous pathogenic fungi. Bacteriol Rev. 1965 Sep;29(3):406–424. doi: 10.1128/br.29.3.406-424.1965. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. HOWARD D. H. Dimorphism of Sporotrichum schenckii. J Bacteriol. 1961 Mar;81:464–469. doi: 10.1128/jb.81.3.464-469.1961. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Kanetsuna F., Carbonell L. M., Azuma I., Yamamura Y. Biochemical studies on the thermal dimorphism of Paracoccidioides brasiliensis. J Bacteriol. 1972 Apr;110(1):208–218. doi: 10.1128/jb.110.1.208-218.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Kanetsuna F., Carbonell L. M. Cell wall composition of the yeastlike and mycelial forms of Blastomyces dermatitidis. J Bacteriol. 1971 Jun;106(3):946–948. doi: 10.1128/jb.106.3.946-948.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Kanetsuna F., Carbonell L. M. Cell wall glucans of the yeast and mycelial forms of Paracoccidioides brasiliensis. J Bacteriol. 1970 Mar;101(3):675–680. doi: 10.1128/jb.101.3.675-680.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kanetsuna F., Carbonell L. M., Moreno R. E., Rodriguez J. Cell wall composition of the yeast and mycelial forms of Paracoccidioides brasiliensis. J Bacteriol. 1969 Mar;97(3):1036–1041. doi: 10.1128/jb.97.3.1036-1041.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Lane J. W., Garrison R. G. Electron microscopy of the yeast to mycelial phase conversion of Sporotrichum schenckii. Can J Microbiol. 1970 Aug;16(8):747–749. doi: 10.1139/m70-127. [DOI] [PubMed] [Google Scholar]
  12. Lane J. W., Grrison R. G., Field M. F. Ultrastructural studies on the yeastlike and mycelial phases of Sporotrichum schenckii. J Bacteriol. 1969 Nov;100(2):1010–1019. doi: 10.1128/jb.100.2.1010-1019.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Lloyd K. O., Bitoon M. A. Isolation and purification of a peptido-rhamnomannan from the yeast form of Sporothrix schenckii. Structural and immunochemical studies. J Immunol. 1971 Sep;107(3):663–671. [PubMed] [Google Scholar]
  14. Mahvi T. A., Spicer S. S., Wright N. J. Cytochemistry of acid mucosubstance and acid phosphatase in Cryptococcus neoformans. Can J Microbiol. 1974 Jun;20(6):833–838. doi: 10.1139/m74-128. [DOI] [PubMed] [Google Scholar]
  15. Nicot J., Mariat F. Caractères morphologique et position systématique de Sporothrix schenckii, agent de la sporotrichose humaine. Mycopathol Mycol Appl. 1973 Jan 31;49(1):53–65. doi: 10.1007/BF02057447. [DOI] [PubMed] [Google Scholar]
  16. Oujezdsky K. B., Grove S. N., Szaniszlo P. J. Morphologica and structural changes during the yeast-to mold conversion of Phialophora dermatitidis. J Bacteriol. 1973 Jan;113(1):468–477. doi: 10.1128/jb.113.1.468-477.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. RINEHART J. F., ABUL-HAJ S. K. An improved method for histologic demonstration of acid mucopolysaccharides in tissues. AMA Arch Pathol. 1951 Aug;52(2):189–194. [PubMed] [Google Scholar]
  18. Toriello C., Mariat F. Etude comparée des polyosides des champignons Ceratocystis stenoceras et Sporothrix schenckii. Composition chimique et analyse immunologique. Ann Microbiol (Paris) 1974 Apr;125A(3):287–307. [PubMed] [Google Scholar]
  19. Travassos L. R., Gorin P. A., Lloyd K. O. Comparison of the rhamnomannans from the human pathogen Sporothrix schenckii with those from the Ceratocystis species. Infect Immun. 1973 Nov;8(5):685–693. doi: 10.1128/iai.8.5.685-693.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES