Release of Protoplasts in the Yeast Phase of Histoplasma capsulatum without Added Enzyme

Abstract

Cells of the yeast phase of the dimorphic systemic fungus pathogen Histoplasma capsulatum readily released large numbers of intact protoplasts without degradation of their cell walls by snail or microbial enzymes, previously regarded as a requirement for all yeast and mycelial fungal forms. Over 90 percent of "B" type yeast cells in the early logarithmic phase of growth released living protoplasts when incubated at 37 degrees C with 2 molar magnesium sulfate, whereas "A" type yeast cells required prior exposure for 24 hours to 2-deoxy-D-glucose before incubation in the 2 molar magnesium sulfate.

Effect of Temperature on Saprophytic Cryptococci: Temperature-induced Lysis and Protoplast Formation

“…The view that wall biosynthesis in C. difluens is perturbed at 37 "C is further substantiated by comparing the morphological consequences of exposing cells to 37 "C and of treatment with the inhibitor a-deoxyglucose at 27 "C. It is known that 2-deoxyglucose blocks wall synthesis in yeast and also causes protoplast formation (Heredia, De La Fuente & Sols, 1964;Berliner & Reca, 1970). Osmotically stabilized cells of C. difluens possess pores when treated with 2-deoxyglucose at a permissive temperature (27 "C); these pores are smaller, however, than those induced at 37 "C. The reason for this difference may be that the cells treated in this manner do not enlarge to the extent which is typical of cells exposed to 37 "C. This failure to increase in size is probably due to an ambivalent effect of the a-deoxyglucose, i.e.…”

History of medical mycology in the united states

“…Fungal molecular genetics. The first report of the successful release of living protoplasts from albino and brown types of H. capsulatum was published by Berliner and Reca (28). The production of spheroplasts was important as a means to study the cell wall composition, physiology, cytology, and genetics of fungi.…”

Induction of protoplast-like cells in Bifidobacterium bifidum Es5. I. Induction of protoplasts and L-forms by penicillin.

“…There are several other reagents for protoplast induction (15), for example, a wall lytic enzyme, an inhibitor of cell wall synthesis, and an autolysin or a nonspecific substance such as glycine or MgSO4 (16). It is well known that penicillin G (PCG) interferes in the cross-linking of peptidoglycan, a final stage in cell wall biosynthesis, and that it kills or lyses sensitive bacteria.…”