Publications by authors named "Steffen Heinz"

The spatial organization of the de novo assembly of photosystem II (PSII) in cyanobacteria, particularly its subcellular starting point, is a matter of ongoing scientific debate. Here, we use fluorescence microscopy and biochemical experiments to demonstrate that the most likely marker of early PSII biogenesis, i.e.

View Article and Find Full Text PDF

Thylakoids are the highly specialized internal membrane systems that harbor the photosynthetic electron transport machinery in cyanobacteria and in chloroplasts. In Synechocystis sp. PCC 6803, thylakoid membranes (TMs) are arranged in peripheral sheets that occasionally converge on the plasma membrane (PM) to form thylakoid convergence membranes (TCMs).

View Article and Find Full Text PDF
Article Synopsis
  • VIPP1 is a crucial protein in cyanobacteria that helps create and maintain thylakoid membranes, which are essential for photosynthesis.
  • Researchers used cryo-electron microscopy to analyze the structure of VIPP1, revealing how its flexible monomers form ring-like structures that aid in membrane binding and curvature.
  • Mutations in VIPP1 lead to issues with thylakoid stability under stress, highlighting its important role in protecting membranes from damage while the study also employs cryo-CLEM to visualize VIPP1's interaction with chloroplast membranes.
View Article and Find Full Text PDF

Plastoglobules are lipoprotein particles that are found in different types of plastids. They contain a very specific and specialized set of lipids and proteins. Plastoglobules are highly dynamic in size and shape, and are therefore thought to participate in adaptation processes during either abiotic or biotic stresses or transitions between developmental stages.

View Article and Find Full Text PDF

In Synechocystis sp. PCC 6803, the flv4-2 operon encodes the flavodiiron proteins Flv2 and Flv4 together with a small protein, Sll0218, providing photoprotection for Photosystem II (PSII). Here, the distinct roles of Flv2/Flv4 and Sll0218 were addressed, using a number of flv4-2 operon mutants.

View Article and Find Full Text PDF

Photosynthesis occurs in thylakoids, a highly specialized membrane system. In the cyanobacterium sp PCC 6803 (hereafter 6803), the thylakoids are arranged parallel to the plasma membrane and occasionally converge toward it to form biogenesis centers. The initial steps in PSII assembly are thought to take place in these regions, which contain a membrane subcompartment harboring the early assembly factor PratA and are referred to as PratA-defined membranes (PDMs).

View Article and Find Full Text PDF

The assembly and repair of photosystem II (PSII) is facilitated by a variety of assembly factors. Among those, the tetratricopeptide repeat (TPR) protein Slr0151 from Synechocystis sp. PCC 6803 (hereafter Synechocystis) has previously been assigned a repair function under high light conditions (Yang et al.

View Article and Find Full Text PDF

Photosystem II (PSII), a large multisubunit membrane protein complex found in the thylakoid membranes of cyanobacteria, algae and plants, catalyzes light-driven oxygen evolution from water and reduction of plastoquinone. Biogenesis of PSII requires coordinated assembly of at least 20 protein subunits, as well as incorporation of various organic and inorganic cofactors. The stepwise assembly process is facilitated by numerous protein factors that have been identified in recent years.

View Article and Find Full Text PDF

Thylakoids mediate photosynthetic electron transfer and represent one of the most elaborate energy-transducing membrane systems. Despite our detailed knowledge of its structure and function, much remains to be learned about how the machinery is put together. The concerted synthesis and assembly of lipids, proteins and low-molecular-weight cofactors like pigments and transition metal ions require a high level of spatiotemporal coordination.

View Article and Find Full Text PDF