[An electron microscopic study of Nocardia rubra growing in a medium containing phenol]

Changes in the cytoplasm were detected in the ultrastructure of Nocardia rubra 80 growing on a medium containing phenol: the cytoplasm aggregated to yield inclusions with different electron density, having round shape and granular structure. The inclusions are surrounded with bright zones. Cells were formed, which resembled bacterial endospores by their formation and structure; however, typical refractive spores with envelopes and cortex have not been detected.