AFM observation of protein translocation mediated by one unit of SecYEG-SecA complex.

Protein translocation across cellular membranes is an essential and nano-scale dynamic process. In the bacterial cytoplasmic membrane, the core proteins in this process are a membrane protein complex, SecYEG, corresponding to the eukaryotic Sec61 complex, and a cytoplasmic protein, SecA ATPase. Despite more than three decades of extensive research on Sec proteins, from genetic experiments to cutting-edge single-molecule analyses, no study has visually demonstrated protein translocation.

Crystal structure of the lipid flippase MurJ in a "squeezed" form distinct from its inward- and outward-facing forms.

The bacterial peptidoglycan enclosing the cytoplasmic membrane is a fundamental cellular architecture. The integral membrane protein MurJ plays an essential role in flipping the cell wall building block Lipid II across the cytoplasmic membrane for peptidoglycan biosynthesis. Previously reported crystal structures of MurJ have elucidated its V-shaped inward- or outward-facing forms with an internal cavity for substrate binding.

The lack of the cell division protein FtsZ induced generation of giant cells under acidic stress in cyanobacterium Synechocystis sp. PCC6803.

Bacteria exposed to environmental stresses often exhibit superior acclimation abilities to environmental change. Acid treatment causes an increase in the cell length of the cyanobacterium Synechocystis sp. PCC6803 under light conditions.

Characterization of Sll1558 in environmental stress tolerance of Synechocystis sp. PCC 6803.

So far, the molecular mechanisms underlying the acidic-stress responses of plants are complicated and only fragmentally understood. Here, we investigated the mechanisms responsible for acidic-stress acclimation. Previously, DNA microarray analysis identified the sll1558 gene in Synechocystis sp.

Characterization of ABC transporter genes, sll1180, sll1181, and slr1270, involved in acid stress tolerance of Synechocystis sp. PCC 6803.

Over 50 ATP-binding cassette (ABC) transporter-related genes are detected in the Synechocystis sp. PCC 6803 genome by genome sequence analysis. Deletion mutants of other substrate-unknown ABC transporter genes were screened for their acid stress sensitivities in a low-pH medium to identify ABC transporters involved in acid resistance.