Cryptococcus neoformans I. Nonencapsulated Mutants

Abstract
Seven nonencapsulated mutants of C. neoformans were isolated from an encapsulated strain of human origin. Initially, the mutants were avirulent for mice. After several months of sub-culturing, 6 of the 7 isolates reverted to the encapsulated state and possessed varying degrees of virulence. The results of these ex-periments suggest that a strong correlation exists between the presence of a capsule and the virulence of C. neoformans.