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Enzyme synthesis in myxamoebae of the cellular slime mould Dictyostelium discoideum during growth in axenic culture.

ABSTRACT: 1. The specific activities of beta-N-acetylglucosaminidase, acid phosphatase, alpha-mannosidase, beta-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 and phase of the growth cycle. 3. The intracellular location of the enzymes studied has been determined. 4. Two enzymes, beta-N-acetylglucosaminidase and alpha-mannosidase, are not only synthesized preferentially as the myxamoebae enter the stationary phase of growth but they are also excreted. The excretion process appears to be specific, because other enzymes that occur in the same intracellular fraction are not excreted.

SUBMITTER: Ashworth JM

PROVIDER: S-EPMC1178417 | biostudies-other | 1972 Feb

REPOSITORIES: biostudies-other

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Metabolism of the cellular slime mould Dictyostelium discoideum grown in axenic culture.

Project description:1. The DNA, RNA, protein and carbohydrate contents of myxamoebae of Dictyostelium discoideum strain Ax-2 were measured after growth on bacteria or in various axenic media. 2. Myxamoebae grown in the different axenic media have similar DNA, RNA and protein contents, but there are marked differences in the contents of glycogen and free sugars. The DNA and protein contents of myxamoebae grown on bacteria are different from those in myxamoebae grown axenically. 3. Approximately half the DNA found in myxamoebae grown on bacteria is of bacterial rather than of slime-mould origin. 4. The specific activities of some enzymes (including UDP-glucose pyrophosphorylase) are higher in myxamoebae grown axenically than in myxamoebae grown on bacteria. Nevertheless the characteristic increase in the specific activity of UDP-glucose pyrophosphorylase occurring during differentiation of cells of the wild-type strain NC-4 is also found in cells grown axenically. 5. The rate of amino acid oxidation during axenic growth of the myxamoebae is decreased when the cells are supplied with glucose.

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Growth of myxameobae of the cellular slime mould Dictyostelium discoideum in axenic culture.

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Enzyme synthesis in the cellular slime mould Dictyostelium discoideum during the differentiation of myxamoebae grown axenically.

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The isolation and characterization of lysosomal particles from myxamoebae of the cellular slime mould Dictyostelium discoideum.

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| S-EPMC1168281 | biostudies-other

Adenosine 3':5'-cyclic monophosphate concentrations and phosphodiesterase activities during axenic growth and differentiation of cells of the cellular slime mould Dictyostelium discoideum.

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Adenosine 3':5'-cyclic monophosphate-binding protein from the cellular slime mould Dictyostelium discoideum.

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| S-EPMC1177739 | biostudies-other

The purification and properties of extracellular glycosidases of the cellular slime mould Dictyostelium discoideum.

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