Ionization Constants pKa of Cardiolipin.
(2013) In PLoS ONE 8(9).- Abstract
- Cardiolipin is a phospholipid found in the inner mitochondrial membrane and in bacteria, and it is associated with many physiological functions. Cardiolipin has a dimeric structure consisting of two phosphatidyl residues connected by a glycerol bridge and four acyl chains, and therefore it can carry two negative charges. The pKa values of the phosphate groups have previously been reported to differ widely with pKa1 = 2.8 and pKa2 = 7.5-9.5. Still, there are several examples of experimental observations from cardiolipin-containing systems that do not fit with this dissociation behavior. Therefore, we have carried out pH-titration and titration calorimetric experiments on two synthetic cardiolipins, 1,1',2,2'-tetradecanoyl cardiolipin, CL... (More)
- Cardiolipin is a phospholipid found in the inner mitochondrial membrane and in bacteria, and it is associated with many physiological functions. Cardiolipin has a dimeric structure consisting of two phosphatidyl residues connected by a glycerol bridge and four acyl chains, and therefore it can carry two negative charges. The pKa values of the phosphate groups have previously been reported to differ widely with pKa1 = 2.8 and pKa2 = 7.5-9.5. Still, there are several examples of experimental observations from cardiolipin-containing systems that do not fit with this dissociation behavior. Therefore, we have carried out pH-titration and titration calorimetric experiments on two synthetic cardiolipins, 1,1',2,2'-tetradecanoyl cardiolipin, CL (C14∶0), and 1,1',2,2'-tetraoctadecenoyl cardiolipin, CL (C18∶1). Our results show that both behave as strong dibasic acids with pKa1 about the same as the first pKa of phosphoric acid, 2.15, and pKa2 about one unit larger. The characterization of the acidic properties of cardiolipin is crucial for the understanding of the molecular organization in self-assembled systems that contain cardiolipin, and for their biological function. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/4065496
- author
- Olofsson, Gerd LU and Sparr, Emma LU
- organization
- publishing date
- 2013
- type
- Contribution to journal
- publication status
- published
- subject
- in
- PLoS ONE
- volume
- 8
- issue
- 9
- article number
- e73040
- publisher
- Public Library of Science (PLoS)
- external identifiers
-
- wos:000324408400016
- pmid:24058458
- scopus:84884169039
- pmid:24058458
- ISSN
- 1932-6203
- DOI
- 10.1371/journal.pone.0073040
- language
- English
- LU publication?
- yes
- id
- 13deca65-7584-4dc1-b91c-42f5a0c5720c (old id 4065496)
- date added to LUP
- 2016-04-01 14:40:27
- date last changed
- 2022-05-08 00:05:26
@article{13deca65-7584-4dc1-b91c-42f5a0c5720c,
abstract = {{Cardiolipin is a phospholipid found in the inner mitochondrial membrane and in bacteria, and it is associated with many physiological functions. Cardiolipin has a dimeric structure consisting of two phosphatidyl residues connected by a glycerol bridge and four acyl chains, and therefore it can carry two negative charges. The pKa values of the phosphate groups have previously been reported to differ widely with pKa1 = 2.8 and pKa2 = 7.5-9.5. Still, there are several examples of experimental observations from cardiolipin-containing systems that do not fit with this dissociation behavior. Therefore, we have carried out pH-titration and titration calorimetric experiments on two synthetic cardiolipins, 1,1',2,2'-tetradecanoyl cardiolipin, CL (C14∶0), and 1,1',2,2'-tetraoctadecenoyl cardiolipin, CL (C18∶1). Our results show that both behave as strong dibasic acids with pKa1 about the same as the first pKa of phosphoric acid, 2.15, and pKa2 about one unit larger. The characterization of the acidic properties of cardiolipin is crucial for the understanding of the molecular organization in self-assembled systems that contain cardiolipin, and for their biological function.}},
author = {{Olofsson, Gerd and Sparr, Emma}},
issn = {{1932-6203}},
language = {{eng}},
number = {{9}},
publisher = {{Public Library of Science (PLoS)}},
series = {{PLoS ONE}},
title = {{Ionization Constants pKa of Cardiolipin.}},
url = {{http://dx.doi.org/10.1371/journal.pone.0073040}},
doi = {{10.1371/journal.pone.0073040}},
volume = {{8}},
year = {{2013}},
}