Back to Search
Start Over
Supramolecular assemblies from lysosomal matrix proteins and complex lipids.
- Source :
- European Journal of Biochemistry; 11/1/97, Vol. 249 Issue 3, p862-869, 8p
- Publication Year :
- 1997
-
Abstract
- Most lysosomal hydrolases are soluble enzymes. Lamp-II (lysosome-associated membrane protein-II) is a major constituent of the lysosomal membrane. We studied the aggregation of a series of lysosomai molecules. The aggregation-sensitive lysosomal marker enzymes were optimally aggregated at intralysosomal pH. A similar pH dependence was recorded for aggregation of Lamp-II. The pH-dependent loss of solubility of isolated Lamp-II required components of the lysosome extract. Conditions of mild acid pH promoting aggregation triggered the formation of complexes with lipids of lysosomal origin. We fractionated a membrane-free lysosome extract by gel-filtration chromatography and could reconstitute assemblies in vitro from separated fractions. We found some selectivity in the lysosomal proteins binding to complex lipids, phosphatidylcholine, sphingomyelin, and phosphatidylethanolamine being most effective. We propose that the formation at pH 5.0 of such supramolecular assemblies between lysosomal proteins and lipids occurs within the intralysosomal environment. Some possible consequences of such an intralysosomal matrix formation on organelle function are discussed. [ABSTRACT FROM AUTHOR]
- Subjects :
- LYSOSOMES
HYDROLASES
ENZYMES
ORGANELLES
CELL membranes
BIOCHEMISTRY
Subjects
Details
- Language :
- English
- ISSN :
- 00142956
- Volume :
- 249
- Issue :
- 3
- Database :
- Complementary Index
- Journal :
- European Journal of Biochemistry
- Publication Type :
- Academic Journal
- Accession number :
- 12478545
- Full Text :
- https://doi.org/10.1111/j.1432-1033.1997.t01-1-00862.x