Lipids in photosynthetic protein complexes in the thylakoid membrane of plants, algae, and cyanobacteria

Abstract

In the thylakoid membrane of cyanobacteria and chloroplasts, many proteins involved in photosynthesis are associated with or integrated in the fluid bilayer matrix formed by four unique glycerolipid classes, monogalactosyldiacylglycerol, digalactosyldiacylglycerol, sulfoquinovosyldiacylglycerol, and phosphatidylglycerol. Biochemical and molecular genetic studies have revealed that these glycerolipids play essential roles not only in the formation of thylakoid lipid bilayers but also in the assembly and functions of photosynthetic complexes. Moreover, considerable advances in structural biology have identified a number of lipid molecules within the photosynthetic complexes such as photosystem I and photosystem II. These data have provided important insights into the association of lipids with protein subunits in photosynthetic complexes and the distribution of lipids in the thylakoid membrane. Here, we summarize the recent high-resolution observations of lipid molecules in the structures of photosynthetic complexes from plants, algae, and cyanobacteria, and evaluate the distribution of lipids among photosynthetic protein complexes and thylakoid lipid bilayers. By integrating the structural information into the findings from biochemical and molecular genetic studies, we highlight the conserved and differentiated roles of lipids in the assembly and functions of photosynthetic complexes among plants, algae, and cyanobacteria.

A cryptic plastid and a novel mitochondrial plasmid inLeucomyxa plasmidiferagen. and sp. nov. (Ochrophyta) push the frontiers of organellar biology

“…Plastids membranes generally contain four types of characteristic structural lipids, the phospholipid phosphatidylglycerol (PG), the galactolipids monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), and the sulfolipid sulfoquinovosyldiacylglycerol (SQDG; Yoshihara and Kobayashi 2022), so it was natural to check L. salinum for the presence of enzymes mediating their synthesis. In plastid-bearing eukaryotes PG is synthesized by a plastid-localised pathway that is, however, typically parallel to a separate pathway producing this phospholipid for the use in other cellular compartments (Michaud et al 2017).…”

Proteomic Analysis Comparison on the Ecological Adaptability of Quinclorac-Resistant Echinochloa crus-galli

“…During photosynthesis, the light-dependent reactions require four major protein complexes, photosystem I (PSI), PSII, cytochrome b6f complex, and ATP synthase. The PSII and PSI reaction centers, where photosynthetic charge separation occurs, consist of several protein subunits and cofactors, such as chlorophylls, carotenoids, and quinones [ 40 ]. Light-harvesting antenna complexes are coupled with the core complexes of both PSs to transfer the absorbed light energy to the reaction centers.…”

Sulfolipid substitution ratios of Microcystis aeruginosa and planktonic communities as an indicator of phosphorus limitation in Lake Erie

“…This presumably represents an optimum balance between SQDG and PG that is reached when P is in adequate or excess supply (Van Mooy and Fredricks 2010). The interaction between these two lipids is an active question (Nakajima et al 2018;Yoshihara and Kobayashi 2022), and the specific biochemical benefit gained from an optimum balance of anionic lipids remains largely unknown (Endo et al 2016).…”