An intramolecular disulfide bond is essential for annexin I-mediated liposome aggregation.
Dithiothreitol (DTT) inhibits the annexin I-mediated aggregation of phosphatidylserine (PS) liposomes, but has no effect on its binding to PS vesicles. Non-reducing SDS gel analysis indicates that intermolecular disulfide bonds between annexin I molecules are not involved in liposome aggregation. However, DTT causes changes in protein conformation of annexin I as monitored by hydrophobic fluorescent dye treatment. The results suggest that the reduction of the intramolecular disulfide bond leads to inhibition of annexin I-mediated liposome aggregation via protein conformational changes.
Liu
L
L
Institute For Environmental Medicine, University of Pennsylvania, School of Medicine, Philadelphia 19104, USA.
Zimmerman
U J
UJ
D000818:Animals; D017305:Annexin A1 / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D002417:Cattle; D004220:Disulfides; D004229:Dithiothreitol / Q000494:pharmacology*; D007700:Kinetics; D008081:Liposomes; D008168:Lung / Q000378:metabolism; D010718:Phosphatidylserines; D011485:Protein Binding; D011487:Protein Conformation / Q000187:drug effects; D013050:Spectrometry, Fluorescence
D017305:Annexin A1; D004220:Disulfides; D008081:Liposomes; D010718:Phosphatidylserines; D004229:Dithiothreitol