{"entity": "journal", "iuid": "a637aea607d641c58b4f1a8ba586baf1", "timestamp": "2026-08-15T06:35:22.473Z", "links": {"self": {"href": "https://publications.scilifelab.se/journal/Biochimica%20et%20Biophysica%20Acta%20%28BBA%29%20-%20Biomembranes.json"}, "display": {"href": "https://publications.scilifelab.se/journal/Biochimica%20et%20Biophysica%20Acta%20%28BBA%29%20-%20Biomembranes"}}, "title": "Biochimica et Biophysica Acta (BBA) - Biomembranes", "issn": "1879-2642", "issn-l": "0005-2736", "publications_count": 5, "publications": [{"entity": "publication", "iuid": "a94753c335e24281bac31343d48a4943", "links": {"self": {"href": "https://publications.scilifelab.se/publication/a94753c335e24281bac31343d48a4943.json"}, "display": {"href": "https://publications.scilifelab.se/publication/a94753c335e24281bac31343d48a4943"}}, "title": "Lipid- and substrate-induced conformational and dynamic changes in a glycosyltransferase involved in E. coli LPS synthesis revealed by 19F and 31P NMR.", "authors": [{"family": "Patrick", "given": "Joan", "initials": "J"}, {"family": "Pettersson", "given": "Pontus", "initials": "P"}, {"family": "M\u00e4ler", "given": "Lena", "initials": "L"}], "type": "journal article", "published": "2023-12-00", "journal": {"title": "Biochimica et Biophysica Acta (BBA) - Biomembranes", "issn": "1879-2642", "volume": "1865", "issue": "8", "pages": "184209", "issn-l": "0005-2736"}, "abstract": "WaaG is a glycosyltransferase (GT) involved in the synthesis of the bacterial cell wall, and in Escherichia coli it catalyzes the transfer of a glucose moiety from the donor substrate UDP-glucose onto the nascent lipopolysaccharide (LPS) molecule which when completed constitutes the major component of the bacterium's outermost defenses. Similar to other GTs of the GT-B fold, having two Rossman-like domains connected by a short linker, WaaG is believed to undergo complex inter-domain motions as part of its function to accommodate the nascent LPS and UDP-glucose in the catalytic site located in the cleft between the two domains. As the nascent LPS is bulky and membrane-bound, WaaG is a peripheral membrane protein, adding to the complexity of studying the enzyme in a biologically relevant environment. Using specific 5-fluoro-Trp labelling of native and inserted tryptophans and 19F NMR we herein studied the dynamic interactions of WaaG with lipids using bicelles, and with the donor substrate. Line-shape changes when bicelles are added to WaaG show that the dynamic behavior is altered when binding to the model membrane, while a chemical shift change indicates an altered environment around a tryptophan located in the C-terminal domain of WaaG upon interaction with UDP-glucose or UDP. A lipid-bound paramagnetic probe was used to confirm that the membrane interaction is mediated by a loop region located in the N-terminal domain. Furthermore, the hydrolysis of the donor substrate by WaaG was quantified by 31P NMR.", "doi": "10.1016/j.bbamem.2023.184209", "pmid": "37558175", "labels": {"Swedish NMR Centre": "Service"}, "xrefs": [{"db": "pii", "key": "S0005-2736(23)00091-3"}], "notes": [], "created": "2023-12-01T21:38:10.000Z", "modified": "2025-10-17T13:03:53.294Z"}, {"entity": "publication", "iuid": "3ab6e9e3e50c4469b11e4b49e8ecad0b", "links": {"self": {"href": "https://publications.scilifelab.se/publication/3ab6e9e3e50c4469b11e4b49e8ecad0b.json"}, "display": {"href": "https://publications.scilifelab.se/publication/3ab6e9e3e50c4469b11e4b49e8ecad0b"}}, "title": "A small molecule screen for paqr-2 suppressors identifies Tyloxapol as a membrane fluidizer for C. elegans and mammalian cells.", "authors": [{"family": "Ruiz", "given": "Mario", "initials": "M"}, {"family": "Svensk", "given": "Emma", "initials": "E"}, {"family": "Einarsson", "given": "Elinor", "initials": "E"}, {"family": "Grahn", "given": "Erik Podda", "initials": "EP"}, {"family": "Pilon", "given": "Marc", "initials": "M"}], "type": "journal article", "published": "2022-09-01", "journal": {"title": "Biochimica et Biophysica Acta (BBA) - Biomembranes", "issn": "1879-2642", "volume": "1864", "issue": "9", "pages": "183959", "issn-l": "0005-2736"}, "abstract": "Defects in cell membrane homeostasis are implicated in numerous disorders, including cancer, neurodegeneration and diabetes. There is therefore a need for a powerful model to study membrane homeostasis and to identify eventual therapeutic routes. The C. elegans gene paqr-2 encodes a homolog of the mammalian AdipoR1 and AdipoR2 proteins that, when mutated, causes a membrane homeostasis defect accompanied by multiple phenotypes such as intolerance to dietary saturated fatty acids, intolerance to cold and a characteristic tail tip morphology defect. We screened a compound library to identify molecules that can suppress the paqr-2 phenotypes. A single positive hit, Tyloxapol, was found that very effectively suppresses multiple paqr-2 phenotypes. Tyloxapol is a non-ionic detergent currently in use clinically as an expectorant. Importantly, we examined the potential of Tyloxapol as a fluidizer in human cells and found that it improves the viability and membrane fluidity of AdipoR2-deficient human cells challenged with palmitic acid, a membrane-rigidifying saturated fatty acid.", "doi": "10.1016/j.bbamem.2022.183959", "pmid": "35588889", "labels": {"Integrated Microscopy Technologies Gothenburg": "Service"}, "xrefs": [{"db": "pii", "key": "S0005-2736(22)00098-0"}], "notes": [], "created": "2023-02-16T08:25:11.440Z", "modified": "2023-02-16T08:25:11.452Z"}, {"entity": "publication", "iuid": "ef5b253a367349f78b67108e4a1ba487", "links": {"self": {"href": "https://publications.scilifelab.se/publication/ef5b253a367349f78b67108e4a1ba487.json"}, "display": {"href": "https://publications.scilifelab.se/publication/ef5b253a367349f78b67108e4a1ba487"}}, "title": "Soluble TatA forms oligomers that interact with membranes: Structure and insertion studies of a versatile protein transporter.", "authors": [{"family": "Pettersson", "given": "Pontus", "initials": "P"}, {"family": "Patrick", "given": "Joan", "initials": "J"}, {"family": "Jakob", "given": "Mario", "initials": "M"}, {"family": "Jacobs", "given": "Malte", "initials": "M"}, {"family": "Kl\u00f6sgen", "given": "Ralf Bernd", "initials": "RB"}, {"family": "Wennmalm", "given": "Stefan", "initials": "S"}, {"family": "M\u00e4ler", "given": "Lena", "initials": "L", "orcid": "0000-0002-9464-4311", "researcher": {"href": "https://publications.scilifelab.se/researcher/7bfca98ce500442788b18afe2c656c53.json"}}], "type": "journal article", "published": "2021-02-01", "journal": {"title": "Biochimica et Biophysica Acta (BBA) - Biomembranes", "issn": "1879-2642", "volume": "1863", "issue": "2", "pages": "183529", "issn-l": "0005-2736"}, "abstract": "The twin-arginine translocase (Tat) mediates the transport of already-folded proteins across membranes in bacteria, plants and archaea. TatA is a small, dynamic subunit of the Tat-system that is believed to be the active component during target protein translocation. TatA is foremost characterized as a bitopic membrane protein, but has also been found to partition into a soluble, oligomeric structure of yet unknown function. To elucidate the interplay between the membrane-bound and soluble forms we have investigated the oligomers formed by Arabidopsis thaliana TatA. We used several biophysical techniques to study the oligomeric structure in solution, the conversion that takes place upon interaction with membrane models of different compositions, and the effect on bilayer integrity upon insertion. Our results demonstrate that in solution TatA oligomerizes into large objects with a high degree of ordered structure. Upon interaction with lipids, conformational changes take place and TatA disintegrates into lower order oligomers. The insertion of TatA into lipid bilayers causes a temporary leakage of small molecules across the bilayer. The disruptive effect on the membrane is dependent on the liposome's negative surface charge density, with more leakage observed for purely zwitterionic bilayers. Overall, our findings indicate that A. thaliana TatA forms oligomers in solution that insert into bilayers, a process that involves reorganization of the protein oligomer.", "doi": "10.1016/j.bbamem.2020.183529", "pmid": "33279512", "labels": {"Integrated Microscopy Technologies Stockholm": "Collaborative"}, "xrefs": [{"db": "pii", "key": "S0005-2736(20)30371-0"}], "notes": [], "created": "2020-12-15T11:41:36.598Z", "modified": "2021-11-10T12:27:09.587Z"}, {"entity": "publication", "iuid": "686338d2dafb4718b48b247c66a356de", "links": {"self": {"href": "https://publications.scilifelab.se/publication/686338d2dafb4718b48b247c66a356de.json"}, "display": {"href": "https://publications.scilifelab.se/publication/686338d2dafb4718b48b247c66a356de"}}, "title": "Oxidatively stressed mitochondria-mimicking membranes: A molecular insight into their organization during apoptosis.", "authors": [{"family": "Dingeldein", "given": "A P G", "initials": "APG"}, {"family": "Sparrman", "given": "T", "initials": "T", "orcid": "0000-0002-4442-6367", "researcher": {"href": "https://publications.scilifelab.se/researcher/f0d27dbd2f014795b1f7aa164d34bada.json"}}, {"family": "Gr\u00f6bner", "given": "G", "initials": "G", "orcid": "0000-0001-7380-8797", "researcher": {"href": "https://publications.scilifelab.se/researcher/85bd86ebc85d4653bc880bc9be25bc80.json"}}], "type": "journal article", "published": "2018-12-00", "journal": {"volume": "1860", "issn": "1879-2642", "issue": "12", "pages": "2644-2654", "title": "Biochimica et Biophysica Acta (BBA) - Biomembranes", "issn-l": "0005-2736"}, "abstract": "Mitochondria are crucially involved in the removal of eukaryotic cells by the intrinsic pathway of programmed cell death (apoptosis). The mitochondrion's outer membrane (MOM) is the platform where this pathway takes place. Upon oxidative stress triggering apoptotic action, the MOM undergoes permeabilization and release of cytochrome c, ultimately causing cell death. This membrane perforation is regulated not only by opposing members of the Bcl-2 protein family meeting at the MOM but also actively the membrane itself. Upon oxidative damage, the membrane undergoes severe reorganization causing an increase in cell death-causing apoptotic Bcl-2 proteins. To understand the active role of MOM, we provided a detailed molecular view of its structural and dynamic reorganization upon oxidative stress by solid-state 13C MAS NMR (magic angle spinning nuclear magnetic resonance) accompanied by calorimetric studies. By focusing on MOM-like vesicles doped with oxidized lipid species, direct polarization 13C MAS NMR provided a quantitative overview and identification of all lipid moieties across the membrane. 1H-13C cross polarization and insensitive nuclei enhanced by polarization transfer MAS NMR generated a dynamic - mobile versus restricted - membrane profile. Oxidized phospholipids significantly perturb the structural membrane organization and increase membrane dynamics. These perturbations are not uniformly distributed as the hydrophobic core is reflecting the melting of lipid chains and increase in molecular disorder directly, whereas the interface and headgroup region undergo complex dynamical changes, reflecting increased intra-molecular flexibility of these moieties. These changes are potentially crucial in augmenting pro-apoptotic action of proteins like Bax.", "doi": "10.1016/j.bbamem.2018.10.007", "pmid": "30296415", "labels": {"Swedish NMR Centre": "Collaborative"}, "xrefs": [{"db": "pii", "key": "S0005-2736(18)30300-6"}], "notes": [], "created": "2018-10-30T08:08:02.332Z", "modified": "2025-10-17T13:03:58.392Z"}, {"entity": "publication", "iuid": "23db4d2aae6f4f2587c16162a3f1bb74", "links": {"self": {"href": "https://publications.scilifelab.se/publication/23db4d2aae6f4f2587c16162a3f1bb74.json"}, "display": {"href": "https://publications.scilifelab.se/publication/23db4d2aae6f4f2587c16162a3f1bb74"}}, "title": "The oxidized phospholipid PazePC promotes permeabilization of mitochondrial membranes by Bax", "authors": [{"family": "Lidman", "given": "Martin", "initials": "M"}, {"family": "Pokorn\u00e1", "given": "\u0160\u00e1rka", "initials": "\u0160"}, {"family": "Dingeldein", "given": "Artur P G", "initials": "APG"}, {"family": "Sparrman", "given": "Tobias", "initials": "T", "orcid": "0000-0002-4442-6367", "researcher": {"href": "https://publications.scilifelab.se/researcher/f0d27dbd2f014795b1f7aa164d34bada.json"}}, {"family": "Wallgren", "given": "Marcus", "initials": "M"}, {"family": "\u0160achl", "given": "Radek", "initials": "R", "orcid": "0000-0002-0441-3908", "researcher": {"href": "https://publications.scilifelab.se/researcher/6b156d9020064ad7badda162f54f7a6a.json"}}, {"family": "Hof", "given": "Martin", "initials": "M", "orcid": "0000-0003-2884-3037", "researcher": {"href": "https://publications.scilifelab.se/researcher/8ee7e14809ee4a579220428faa1cb058.json"}}, {"family": "Gr\u00f6bner", "given": "Gerhard", "initials": "G", "orcid": "0000-0001-7380-8797", "researcher": {"href": "https://publications.scilifelab.se/researcher/85bd86ebc85d4653bc880bc9be25bc80.json"}}], "type": "journal-article", "published": "2016-06-00", "journal": {"volume": "1858", "issn": "0005-2736", "issue": "6", "pages": "1288-1297", "title": "Biochimica et Biophysica Acta (BBA) - Biomembranes", "issn-l": null}, "abstract": "Mitochondria play a crucial role in programmed cell death via the intrinsic apoptotic pathway, which is tightly regulated by the B-cell CLL/lymphoma-2 (Bcl-2) protein family. Intracellular oxidative stress causes the translocation of Bax, a pro-apoptotic family member, to the mitochondrial outer membrane (MOM) where it induces membrane permeabilization. Oxidized phospholipids (OxPls) generated in the MOM during oxidative stress directly affect the onset and progression of mitochondria-mediated apoptosis. Here we use MOM-mimicking lipid vesicles doped with varying concentrations of 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC), an OxPl species known to significantly enhance Bax-membrane association, to investigate three key aspects of Bax's action at the MOM: 1) induction of Bax pores in membranes without additional mediator proteins, 2) existence of a threshold OxPl concentration required for Bax-membrane action and 3) mechanism by which PazePC disturbs membrane organization to facilitate Bax penetration. Fluorescence leakage studies revealed that Bax-induced leakage, especially its rate, increased with the vesicles' PazePC content without any detectable threshold neither for OxPl nor Bax. Moreover, the leakage rate correlated with the Bax to lipid ratio and the PazePC content. Solid state NMR studies and calorimetric experiments on the lipid vesicles confirmed that OxPl incorporation disrupted the membrane's organization, enabling Bax to penetrate into the membrane. In addition, 15N cross polarization (CP) and insensitive nuclei enhanced by polarization transfer (INEPT) MAS NMR experiments using uniformly (15)N-labeled Bax revealed dynamically restricted helical segments of Bax embedded in the membrane, while highly flexible protein segments were located outside or at the membrane surface.", "doi": "10.1016/j.bbamem.2016.03.003", "pmid": "26947183", "labels": {"Swedish NMR Centre": "Collaborative"}, "xrefs": [{"db": "pii", "key": "S0005-2736(16)30080-3"}], "notes": [], "created": "2017-05-08T08:00:02.335Z", "modified": "2026-06-29T06:57:59.190Z"}], "created": "2018-10-30T08:08:02.340Z", "modified": "2020-11-27T13:14:07.960Z"}