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: Isolation and solubilization of casein kinase from Golgi apparatus of bovine mammary gland and phosphorylation of peptides.
    Author: Szymanski ES, Farrell HM.
    Journal: Biochim Biophys Acta; 1982 Apr 03; 702(2):163-72. PubMed ID: 6952938.
    Abstract:
    Phosphate incorporation from [gamma-32P]ATP into native and dephosphorylated alpha s1-casein is catalyzed by a casein kinase localized in the Golgi apparatus of lactating bovine mammary gland. Casein kinase from the Golgi is activated with either Mg2+ or Ca2+, and increased specific activity is observed with dephosphorylated casein as the substrate. The casein kinase can be solubilized from Golgi apparatus by the non-ionic detergent, Triton X-100. Gel permeation chromatography on Sepharose CL-4B yields a Stokes radius of 10 nm for the detergent-solubilized casein kinase. Dephosphorylated beta-peptide, the amino-terminal peptide from beta-casein, is a good substrate for the solubilized casein kinase. With dephosphorylated beta-peptide, the maximal velocity is 9.1 and 12.0 nmol/min per mg protein with Mg2+ and Ca2+ activation, respectively. The Michaelis constant for beta-peptide is greater with Ca2+ than with Mg2+ (4.8 mg/ml compared to 0.97 mg/ml). However, the Michaelis constant for ATP is not greatly influenced by these metal ions. The Triton X-100-solubilized Golgi enzyme can also catalyze the phosphorylation of peptides, such as fibrinopeptide A and alpha-melanocyte stimulating hormone.
    [Abstract] [Full Text] [Related] [New Search]