FASEB J. Pierce now sold as Thermo Scientific
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

(The FASEB Journal. 2008;22:811.2)
© 2008 FASEB
This Article
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Abdullahi, G. E.
Right arrow Articles by Weers, P. M.M.
PubMed
Right arrow Articles by Abdullahi, G. E.
Right arrow Articles by Weers, P. M.M.
(The FASEB Journal. 2008;22:811.2.)
© 2008 FASEB

811.2

Apolipoprotein-lipid binding: importance of lysine {varepsilon}-amino groups

Gezman Ezedine Abdullahi and Paul M.M. Weers

Chemistry and Biochemistry, California State University, Long Beach, Long Beach, CA

ABSTRACT

Apolipophorin III (apoLp-III) from Locusta migratoria is an 18 kDa model apolipoprotein that plays an integral role in lipid transport via association with circulating lipoproteins. Prior studies have indicated the importance of ionic forces in lipid-protein interactions. In the present study, the possibility of electrostatic interactions between lysine residues on the surface of apoLp-III and phospholipid head groups was investigated. The 7 lysine groups of apoLp-III were chemically modified with the introduction of acetyl (Ac) groups. Guanidine-HCl denaturation studies of modified and unmodified apoLp-III showed minimal changes in denaturation profiles, with 0.62 M and 0.56 M denaturation midpoints, respectively. Circular dichroism spectroscopy revealed a 46% {alpha}-helical content for Ac-apoLp-III, compared to 60% for unmodified apoLp-III. Lipid binding was assessed using dimyristoylphosphatidylcholine small unilamellar vesicles (SUVs). No changes were observed for either type of apoLp-III in their ability to solubilize SUVs and conversion into nanodiscs. When using negatively charged dimyristoylphosphatidylglycerol, Ac-apoLp-III displayed a decreased ability in SUV solubilization. The results indicate the retention of secondary structure in Ac-apoLp-III and provide evidence for the role of lysine residues in association with anionic but not zwitterionic phospholipids.





This Article
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Abdullahi, G. E.
Right arrow Articles by Weers, P. M.M.
PubMed
Right arrow Articles by Abdullahi, G. E.
Right arrow Articles by Weers, P. M.M.