|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
First published online October 27, 2004
doi: 10.1242/10.1242/jcs.01485
Research Article |
1 Department of Biochemistry and Biocenter Oulu
2 Department of Pathology, University of Oulu, PO Box 3000, FI-90014 Oulu, Finland
* Authors for correspondence (e-mail: vasily.antonenkov{at}oulu.fi; kalervo.hiltunen{at}oulu.fi)
Accepted 6 August 2004
The functional role of the peroxisomal membrane as a permeability barrier to metabolites has been a matter of controversy for more than four decades. The initial conception, claiming free permeability of the membrane to small solute molecules, has recently been challenged by several observations suggesting that the peroxisomal membrane forms a closed compartment. We have characterized in vitro the permeability of rat liver peroxisomal membrane. Our results indicate that the membrane allows free access into peroxisomes for small hydrophilic molecules, such as substrates for peroxisomal enzymes (glycolate, urate), but not to more bulky cofactors (NAD/H, NADP/H, CoA). Although access for cofactors is not prevented completely by the membrane, the membrane barrier severely restricts their rate of entry into peroxisomes. The data lead to conclusion that, in vivo, peroxisomes may possess their own pool of cofactors, while they share a common pool of small metabolites with the cytoplasm. The results also indicate that molecular size plays an important role in in vivo distinction between cofactors and metabolic intermediates.
Key words: Peroxisomes, Membrane permeability, Cofactors
This article has been cited by other articles:
![]() |
S.-J. Reilly, V. Tillander, R. Ofman, S. E.H. Alexson, and M. C. Hunt The Nudix Hydrolase 7 is an Acyl-CoA Diphosphatase Involved in Regulating Peroxisomal Coenzyme A Homeostasis J. Biochem., November 1, 2008; 144(5): 655 - 663. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Islinger, G. H. Luers, K. W. Li, M. Loos, and A. Volkl Rat Liver Peroxisomes after Fibrate Treatment: A SURVEY USING QUANTITATIVE MASS SPECTROMETRY J. Biol. Chem., August 10, 2007; 282(32): 23055 - 23069. [Abstract] [Full Text] [PDF] |
||||