Charlotte C. Campbell

An amino acid liquid synthetic medium for the development of mycelial and yeast forms of Candida albicans

A chemically defined medium composed of 6 amino acids, biotin, inorganic salts and glucose for the growth of yeast and mycelial phases of Candida albicans at 25 degrees C and 37 degrees of C respectively was developed based on the aminopeptidase(s) profile of the fungus. This medium has proved successful in maintaining the growth characteristics of both phases during serial transfers. The relative pathogenicity, virulence, invasiveness and immunogenicity of the yeast and mycelial phases are discussed.

Serology in the respiratory mycoses

This report is an effort to summarize the most recent developments in antigens and serologic tests used for the diagnosis and prognosis of histoplasmosis, blastomycosis, coccidioidomycosis, paracoccidioidomycosis and cryptococcosis. Studies by means of immunodiffusion (ID) in agar gels (AG), viz.; various modifications of the procedure described by Ouchterlony, are emphasized. The absence of standardization in terminology of either this test—ID, AG or Ouchterlony—or the antigenic constituents reactive at different stages of the infections or diseases is perhaps representative of the confusion currently existing in the serologic study of the respiratory mycoses.

Amino acid synthetic media for fungal pathogens based on aminopeptidase specificities: Histoplasma capsulatum, Blastomyces dermititidis, Paracoccidioides brasiliensis and Cryptococcus neoformans.

The development of simple and chemically defined liquid media for Histoplasma capsulatum, Blastomyces dermatitidis, Paracoccidioides brasiliensis and Crypto-occus neoformans according to their aminopeptidases profiles as amino acid requirement was described. When 1.5% purified agar was added, these media also supported excellent mycelial growth and sporulation of the deep mycoses. H. capsulatum was converted to and maintained in yeast phase when 0.1% L-cystine was added to the solid medium incubated at 37 degrees C.

Growth curves with yeast phase of Histoplasma capsulatum

Growth curves can be determined for yeast phase H. capsulatum and can be predicted in successive transfers if initiated from cells in the exponential phase of growth. The procedure is applicable to all strains which can be propagated in the yeast phase. The growth curve, however, must be predetermined for each strain in the liquid medium in which studies are to be carried out.

Feathers as substrate for Histoplasma capsulatum in its filamentous phase of growth

Although Histoplasma capsulatum is not regarded as keratinophilic, feathers from chickens or germ-free quail suspended in water supported good growth of 70 strains of the organism in the filamentous phase for an extended period. Restoration of typical microconidia and macroconidia was noted in many, suggesting that the feather merits further investigation as substrate for preservation of stock collections.

Isolation of Histoplasma capsulatum from feathers of chickens inoculated intravenously and subcutaneously with the yeast phase of the organism

Histoplasma capsulatum was isolated from the feathers of 3 of 4 chickens intravenously or subcutaneously inoculated with the yeast phase of this agent. Because of the lower temperature of feathers, the findings suggest that these integumenta merit further consideration in the establishing of foci of H. capsulatum in nature. The possible means by which this might occur are discussed.