Tetrahymena pyriformis extract

Figure 4. Sephadex G-50 filtration of Tetrahymena pyriformis extract. Results are plotted as insulin immunoactivity in each fraction using a porcine insulin radioimmunoassay. The horizontal line represents those fractions tested and the lower level of sensitivity of the assay. The left arrow (Vo) represents the void volume, the right arrow (Vt) represents the salt elution position, and the middle arrow represents the region where 1251-insulin and purified porcine insulin elutes on the same column. (Reproduced from Ref. 4.)...

Extraction of Insulin-Related Material and Other Peptide Hormones from Tetrahymena pyriformis... 

This paper describes the various procedures developed and adapted for the extraction and identification of these hormonal peptides in Tetrahymena pyriformis. 

Figure 3. Sep-Pak (C g) purification of insulin-related material. I-insulin and purified porcine insulin were added to separate batches of Tetrahymena pyriformis homogenates and applied to Sep-Pak cartridges. Following elution from the Sep-Pak each gradient fraction was tested for recovery of the exogenously added insulin. The results for each fraction are expressed as the percent of the total material recovered. Key , endogenous insulin Tetrahymena , 125i-insulin added to extract 0, porcine insulin added to extract.

Figure 6. Somatostatin-like material in Tetrahymena pyriformis. Key (right panel) , synthetic somatostatin O, Tetrahymena extract (HPLC purified) Band , anti-somatostatin antibody added. (Reproduced from Ref. 8.)...

Figure 7. ACTH-like material in Tetrahymena pyriformis. (bottom panel) , the extract x, synthetic human ACTH standard O, anti-ACTH antiserum , Sepharose-protein A immunodepletion. (Reproduced from Ref. 5).

Purified preparations of thymidine kinase have also been obtained from animal tumors [187,188]. These are similar to the E. coli enzyme in their susceptibility to feedback inhibition by dTTP, but no activators other than ATP have been identified. Sigmoidal kinetics with ATP as substrate are obtained with an aggregated form of the enzyme, but not with the disaggregated enzyme. Both forms of the enzyme show complex inhibition by dTTP. Thymidine kinase has also been studied in crude extracts of Tetrahymena pyriformis [189], and in this case no inhibition by dTTP was evident. 

Chemotactic activity of substances extracted from L. inflata was investigated in the frequently used eukaryotic ciliate model, Tetrahymena pyriformis GL [64, 65]. The chemotactic activity of cells was measured in a concentration course study (v/v% = 10 -10 ) by capillary assay [66]. The extracts of L. inflata (total extract in methanol, lobeUne HCl, and polyacetylenes) proved to elicit diverse migratory responses (1) a wide range chemoattractant character of the total extract was registered while (2) lobeUne HQ and polyacetylene had strong chemorepellent effects (Fig. 11.32). 

Fig. 11.32 Chemotactic activity of lobeline (repellent), polyacetylenes (repellent) and Lobelia inflata extract (attractant) in Tetrahymena pyriformis...

Figure 5. Insulin-related bioactivity of the extract of Tetra-hymena pyriformis. Key , pork insulin standard A, Tetra-hymena extract , Tetrahymena with anti-insulin antibody added. Reproduced from RefT 4. )...

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