These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Comparison of the effect of tautomycin and phorbol ester on protein kinase C in a cell-free system.
    Author: Magae J, Osada H, Nagai K, Yamasaki M, Isono K.
    Journal: J Antibiot (Tokyo); 1989 Aug; 42(8):1290-3. PubMed ID: 2759909.
    Abstract:
    The effect of tautomycin (TM) on protein kinase C (PKC) was studied in a cell-free system. TM, like phorbol dibutyrate (PDBu), enhanced both base-line and Ca2+/phospholipids-dependent protein kinase activity. However, PDBu but not TM increased the affinity of the enzyme for calcium ions (Ca2+), suggesting that TM is a new activator of PKC, distinct from PDBu. In the presence of 10 micrograms/ml phosphatidyl inositol, the activity of PKC reached maximum at 10(-3) M Ca2+ concentration when the other co-factors were absent. Both TM and PDBu increased the maximum level of PKC activity at the optimum concentration of Ca2+, suggesting that they interacted with the site of PKC which is distinct from the site where Ca2+ interacts. TM and PDBu did not activate the enzyme when protamine sulfate in place of histone III-S was used as a substrate, indicating that they activate PKC by affecting the regulatory domain of the enzyme.
    [Abstract] [Full Text] [Related] [New Search]