The P4 variant of is characterized by the production of fruiting structures in which the overall proportion of stalk to spore material is increased, relative to the wild type. The altered morphology of the mutant is due to increased sensitivity to cyclic AMP which promotes stalk cell differentiation. In the presence of 10 M-cyclic AMP the entire population of P4 amoebae forms clumps of stalk cells on the surface of the dialysis membrane support.

Measurement of changes in activity of a range of developmentally-regulated enzymes during the development of P4 in the presence and absence of cyclic AMP has allowed us to identify three classes of enzyme: (i) Those, such as β-glucosidase II, trehalose-6-phosphate synthetase and uridine diphosphogalactose-4-epimerase, which are required for the production of spores, (ii) Enzymes, primarily but perhaps not exclusively, required during stalk cell formation. Typical of these are -acetylglucosaminidase and alkaline phosphatase. (iii) General enzymes, such as threonine dehydrase, α-mannosidase and uridine diphosphoglucose pyrophosphorylase, which are present in both pre-stalk and pre-spore cells and appear to be necessary for the development of both cell types.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error