Lipid Polymorphism of the Subchloroplast-Granum and Stroma Thylakoid Membrane-Particles. II. Structure and Functions

DLOUHY, Ondrej, Vaclav KARLICKY, Rameez ARSHAD, Otto ZSIROS, Ildiko DOMONKOS, Irena KURASOVA, Andras F WACHA, Tomas MOROSINOTTO, Attila BOTA, Roman KOURIL, Vladimir SPUNDA a Gyozo GARAB. Lipid Polymorphism of the Subchloroplast-Granum and Stroma Thylakoid Membrane-Particles. II. Structure and Functions. Advances in Fuel Cells. BASEL: Elsevier, 2021, roč. 10, č. 9, s. 1-19. ISSN 1752-301X. Dostupné z: https://dx.doi.org/10.3390/cells10092363.

Základní údaje

• Originální název: Lipid Polymorphism of the Subchloroplast-Granum and Stroma Thylakoid Membrane-Particles. II. Structure and Functions
• Autoři: DLOUHY, Ondrej, Vaclav KARLICKY, Rameez ARSHAD, Otto ZSIROS, Ildiko DOMONKOS, Irena KURASOVA, Andras F WACHA, Tomas MOROSINOTTO, Attila BOTA, Roman KOURIL, Vladimir SPUNDA a Gyozo GARAB.
• Vydání: Advances in Fuel Cells, BASEL, Elsevier, 2021, 1752-301X.

Další údaje

• Originální jazyk: angličtina
• Typ výsledku: Článek v odborném periodiku
• Obor: 10601 Cell biology
• Stát vydavatele: Švýcarsko
• Utajení: není předmětem státního či obchodního tajemství
• WWW: URL
• Organizační jednotka: CIISB
• Doi: http://dx.doi.org/10.3390/cells10092363
• UT WoS: 000699266100001
• Klíčová slova anglicky: bilayer; chlorophyll fluorescence; cryo-electron-tomography; electron microscopy; membrane energization; membrane networks; non-bilayer lipid phases; SAXS; violaxanthin de-epoxidase
• Štítky: CF CRYO, ne MU
• Příznaky: Mezinárodní význam, Recenzováno

Anotace

In Part I, by using P-31-NMR spectroscopy, we have shown that isolated granum and stroma thylakoid membranes (TMs), in addition to the bilayer, display two isotropic phases and an inverted hexagonal (H-II) phase; saturation transfer experiments and selective effects of lipase and thermal treatments have shown that these phases arise from distinct, yet interconnectable structural entities. To obtain information on the functional roles and origin of the different lipid phases, here we performed spectroscopic measurements and inspected the ultrastructure of these TM fragments. Circular dichroism, 77 K fluorescence emission spectroscopy, and variable chlorophyll-a fluorescence measurements revealed only minor lipase- or thermally induced changes in the photosynthetic machinery. Electrochromic absorbance transients showed that the TM fragments were re-sealed, and the vesicles largely retained their impermeabilities after lipase treatments-in line with the low susceptibility of the bilayer against the same treatment, as reflected by our P-31-NMR spectroscopy. Signatures of H-II-phase could not be discerned with small-angle X-ray scattering-but traces of H-II structures, without long-range order, were found by freeze-fracture electron microscopy (FF-EM) and cryo-electron tomography (CET). EM and CET images also revealed the presence of small vesicles and fusion of membrane particles, which might account for one of the isotropic phases. Interaction of VDE (violaxanthin de-epoxidase, detected by Western blot technique in both membrane fragments) with TM lipids might account for the other isotropic phase. In general, non-bilayer lipids are proposed to play role in the self-assembly of the highly organized yet dynamic TM network in chloroplasts.