Ultrastructure and Invertase Secretion of the Slime Mutant of Neurospora crassa

SUMMARY: Electron micrographs of thin sections of cells of the slime mutant of Neurospora crassa showed that it, like artificially prepared protoplasts, possessed no cell wall. Invertase was produced by the mutant and appeared to be serologically identical to wild-type N. crassa invertase. The mutant secreted over 95 % of the invertase into the medium whereas cells of the wild-type retained almost all the invertase. The slime mutant hence resembles wild-type protoplasts in both structure and invertase secretion.