Assessing heterogeneity of peroxisomes: isolation of two subpopulations from rat liver.
Peroxisomes exhibit a heterogeneous morphological appearance in rat liver tissue. In this respect, the isolation and subsequent biochemical characterization of peroxisome species from different subcellular prefractions should help to solve the question of whether peroxisomes indeed diverge into functionally specialized subgroups in one tissue. As a means to address this question, we provide a detailed separation protocol for the isolation of peroxisomes from both the light (LM-Po) and the heavy (HM-Po) mitochondrial prefraction for their subsequent comparative analysis. Both isolation strategies rely on centrifugation in individually adapted Optiprep gradients. In case of the heavy mitochondrial fraction, free flow electrophoresis is appended as an additional separation step to yield peroxisomes of sufficient purity. In view of their morphology, peroxisomes isolated from both fractions are surrounded by a continuous single membrane and contain a gray-opaque inner matrix. However, beyond this overall similar appearance, HM-Po exhibit a smaller average diameter, float at lower density, and show a more negative average membrane charge when compared to LM-Po.
Department of Anatomy and Cell Biology, Medical Cell Biology, University of Heidelberg, Heidelberg, Germany. mislinger@ua.pt
Markus
M
Islinger
Afsaneh
A
Abdolzade-Bavil
Sven
S
Liebler
Gerhardt
G
Weber
Alfred
A
Völkl
D000135:Acid Phosphatase / Q000737:chemistry / Q000302:isolation & purification; D000818:Animals; D002374:Catalase / Q000737:chemistry / Q000302:isolation & purification; D002457:Cell Extracts / Q000302:isolation & purification*; D002458:Cell Fractionation / Q000379:methods*; D002499:Centrifugation, Density Gradient; D057075:Enzyme Assays; D004950:Esterases / Q000737:chemistry / Q000302:isolation & purification; D008099:Liver / Q000378:metabolism*; D051379:Mice; D008930:Mitochondria, Liver / Q000378:metabolism / Q000648:ultrastructure; D020675:Peroxisomes / Q000201:enzymology / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D013385:Succinate Dehydrogenase / Q000737:chemistry / Q000302:isolation & purification
D002457:Cell Extracts; D002374:Catalase; D013385:Succinate Dehydrogenase; D004950:Esterases; D000135:Acid Phosphatase