J. Lipid Res. Please sign the JLR Guestbook
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Fless, G. M.
Right arrow Articles by Scanu, A. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fless, G. M.
Right arrow Articles by Scanu, A. M.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?
The Journal of Lipid Research, Vol. 40, 583-592, April 1999
Copyright © 1999 by Lipid Research, Inc.

Original Article

Effect of phospholipase A2 digestion on the conformation and lysine/fibrinogen binding properties of human lipoprotein[a]

Gunther M. Flessa, Elliot W. Kirka, Olga Klezovitcha, José Y. Santiagoa, Celina Edelsteina, Jane Hoover-Plowc, and Angelo M. Scanua,b
a Department of Medicine, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637
b Department of Biochemistry and Molecular Biology, University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637
c Department of Molecular Cardiology, Joseph J. Jacobs Center for Thrombosis and Vascular Biology/FF20, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195

Correspondence to: Gunther M. Fless

In vitro hydrolysis of human lipoprotein[a] (Lp[a]) by phospholipase A2 (PLA2) decreased the phosphatidylcholine (PC) content by 85%, but increased nonesterified fatty acids 3.2-fold and lysoPC 12.9-fold. PLA2-treated Lp[a] had a decreased molecular weight, increased density, and greater electronegativity on agarose gels. In solution, PLA2-Lp[a] was a monomer, and when assessed by sedimentation velocity it behaved like untreated Lp[a], in that it remained compact in NaCl solutions but assumed the extended form in the presence of 6-amino hexanoic acid, which was shown previously to have an affinity for the apo[a] lysine binding site II (LBS II) comprising kringles IV5–8. We interpreted our findings to indicate that PLA2 digestion had no effect on the reactivity of this site. This conclusion was supported by the results obtained from lysine Sepharose and fibrinogen binding experiments, in the presence and absence of Tween 20, showing that phospholipolysis had no effect on the reactivity of the LBS-II domain. A comparable binding behavior was also exhibited by the free apo[a] derived from each of the two forms of Lp[a]. We did observe a small increase in affinity of PLA2-Lp[a] to lysine Sepharose and attributed it to changes in reactivity of the LBS I domain (kringle IV10) induced by phospholipolysis.

In conclusion, the extensive modification of Lp[a] caused by PLA2 digestion had no significant influence on the reactivity of LBS II, which is the domain involved in the binding of apo[a] to fibrinogen and apoB-100. These results also suggest that phospholipids do not play an important role in these interactions.—Fless, G. M., E. W. Kirk, O. Klezovitch, J. Y. Santiago, C. Edelstein, J. Hoover-Plow, and A. M. Scanu. Effect of phospholipase A2 digestion on the conformation and lysine/fibrinogen binding properties of human lipoprotein[a]. J. Lipid Res. 1999. 40: 583–592.

Supplementary key words: Lp[a] structure, apo[a], apoB, lysine binding sites, phosphatidylcholine, lysophosphatidylcholine, 6-aminohexanoic acid, fibrinogen, Tween 20, sedimentation velocity


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 All ASBMB Journals   Journal of Biological Chemistry 
 Molecular and Cellular Proteomics   ASBMB Today 
Copyright © 1999 by the American Society for Biochemistry and Molecular Biology.