Isolation and ultrastructural examination of conidial wall components of Coccidioides and Aspergillus.

The role of the propagule in the initiation of fungal disease is not fully appreciated. Knowledge of the nature of early interactions between infectious propagules and host tissue during onset of respiratory mycoses is particularly scanty. This stems partly from lack of sufficient data on the structure, chemical composition and immunological activity of the microbial surface. In this study, a technique is described for isolation and subsequent ultrastructural examination of the surface wall components of infectious propagules (conidia) produced by the respiratory fungal pathogens, Coccidioides immitis and Aspergillus fumigatus. The SEM has proved very useful in monitoring the cell shearing procedure employed for isolation of the outer conidial wall fractions.