These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Roles of lysine residues and N-terminal alpha-amino group in membrane-damaging activity of Taiwan cobra cardiotoxin 3 toward anionic and zwitterionic phospholipid vesicles.
    Author: Chiou YL, Kao PH, Liu WH, Lin SR, Chang LS.
    Journal: Toxicon; 2010; 55(2-3):256-64. PubMed ID: 19647762.
    Abstract:
    In contrast to a slight increase in activity toward phosphatidylcholine (EYPC)/dimyristoyl phosphatidic acid (DMPA) vesicles, guanidination of Naja naja atra cardiotoxin 3 (CTX3) and selective trinitrophenylation of N-terminal alpha-amino group enhanced notably membrane-damaging activity on EYPC/egg yolk sphingomyelin (EYSM) vesicles. Chemically modified CTX3 showed a reduction in its hemolytic activity and cytotoxicity. These reflected that membrane-damaging activity of CTX3 was affected by phospholipid compositions. Phospholipid-binding capability and oligomeric assembly upon binding with lipid vesicles did not closely correlate with membrane-damaging potency of native and modified CTX3. Moreover, different topographical contacts and distinctive modes for the binding of CTX3 and its modified derivatives with anionic phospholipid vesicles (EYPC/DMPA) and zwitterionic phospholipid vesicles (EYPC/EYSM) were observed. Compared with in the case of EYPC/DMPA, the interaction between CTX molecules and EYPC/EYSM was drastically reduced by increasing salt concentration and heparin. Taken together, our data indicate that guanidination of Lys residues and trinitrophenylation of alpha-amino group alter differently the interacted modes upon absorption on anionic phospholipid vesicles and zwitterionic phospholipid vesicles. The findings also suggest that positively charged residues of CTX3 play a distinctive role in damaging anionic and zwitterionic phospholipid vesicles.
    [Abstract] [Full Text] [Related] [New Search]