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: Hydrodynamic parameters and isolation of mitochondria, microperoxisomes and microsomes of rat heart. Author: Norseth J, Normann PT, Flatmark T. Journal: Biochim Biophys Acta; 1982 Dec 17; 719(3):569-79. PubMed ID: 7150662. Abstract: 1. Analytical differential centrifugation of rat heart homogenates revealed a single population of mitochondria and microperoxisomes. Using cytochrome c oxidase, malate dehydrogenase and amine oxidase as mitochondrial marker enzymes, the s-value of mitochondria was estimated to s = 10326 +/- 406 S (average for the three marker enzymes). The s-value of microperoxisomes was found to be s = 1381 +/- 40 S using catalase as the marker enzyme. The s-value for the two organelles did not change significantly when the isoosmotic sucrose medium was substituted by an isoosmotic mannitol medium. 2. Analytical differential centrifugation revealed a polydispercity of the microsomal fraction using glucose-6-phosphatase and NADPH-cytochrome c reductase as the marker enzymes. The s-values were found to be sH1 = 1569 +/- 412 S (NADPH-cytochrome c reductase), sH2 = 1195 +/- 400 S (glucose-6-phosphatase) and sL = 153 +/- 28 S (NADPH-cytochrome c reductase and glucose-6-phosphatase). The recovery of marker enzymes in the isolated subcellular fractions was in the range of 84-94%. 3. When the mitochondrial and microperoxisomal fractions were subjected to isopycnic gradient centrifugation, using a self-generating gradient of polyvinylpyrrolidone-coated colloidal silica particles (Percoll) in 0.25 M sucrose medium, buoyant densities of 1.10 g/cm3 (main fraction of mitochondria) and 1.06 g/cm3 (main fraction of microperoxisomes) were obtained. The density gradient centrifugation separated microperoxisomes from contaminating lysosomes of high specific activity in acid phosphatase. A value 1.04 g/cm3 was found for the density of the microsomal fraction. 4. Based on the estimated s-values, an optimal procedure is described for the isolation of mitochondrial and microperoxisomal fractions from rat heart muscle.[Abstract] [Full Text] [Related] [New Search]