Liquid Culture of Amoebae of Dictyostelium discoideum Using Dead Bacteria

Dictyostelium discoideum during Growth in Axenic Culture

1. The specific activities of fl-N-acetylglucosaminidase, acid phosphatase, ac-mannosidase, P-glucosidase, UDP-glucose pyrophosphorylase and alkaline phosphatase have been determined in myxamoebae of the cellular slime mould Dictyostelium discoideum Ax-2 grown on different media and in different phases of the growth cycle. 2. Variations in enzymic composition occur with changes in growth medium...

The Growth of Dictyostelium discoideum upon Pathogenic Bacteria.

Species of the Dictyosteliaceae, a group of pseudoplasmodiumforming slime molds, are not uncommon in nature and can be readily isolated from soils, from decaying vegetation and from the dung of various animals. In contrast to the Myxogastrales which possess true plasmodia, the Dictyosteliaceae are characterized by myxamoebae which retain their identity throughout the whole life cycle of the org...

Visualization of actin fibers associated with the cell membrane in amoebae of Dictyostelium discoideum.

Amoebae of Dictyostelium discoideum were attached to a surface coated with polylysine, and the upper portion of the cells was sheared off with a stream of buffer. Scanning and transmission electron microscopy showed that the cytoplasmic surface of the exposed membrane was covered with fibers consisting of actin-containing filaments. The actin was identified by its solubility properties and its ...

Cost of movement in the multicellular stage of the social amoebae Dictyostelium discoideum and D. purpureum

Ammonia promotes accumulation of intracellular cAMP in differentiating amoebae of Dictyostelium discoideum.

We used sporogenous mutants of Dictyostelium discoideum to investigate the mechanism(s) by which exogenous NH4Cl and high ambient pH promote spore formation during in vitro differentiation. The level of NH4Cl required to optimize spore formation is correlated inversely with pH, indicating that NH3 rather than NH4+ is the active species. The spore-promoting activity of high ambient pH (without e...