The Bacterial Cytoplasmic Membrane

Protein translocation across the bacterial cytoplasmic membrane.

About 25% to 30% of the bacterial proteins function in the cell envelope or outside of the cell. These proteins are synthesized in the cytosol, and the vast majority is recognized as a ribosome-bound nascent chain by the signal recognition particle (SRP) or by the secretion-dedicated chaperone SecB. Subsequently, they are targeted to the Sec translocase in the cytoplasmic membrane, a multimeric...

Protein targeting to the bacterial cytoplasmic membrane.

Proteins that perform their activity within the cytoplasmic membrane or outside this cell boundary must be targeted to the translocation site prior to their insertion and/or translocation. In bacteria, several targeting routes are known; the SecB- and the signal recognition particle-dependent pathways are the best characterized. Recently, evidence for the existence of a third major route, the t...

Cytoplasmic membrane iron permease systems in the bacterial cell envelope.

Iron is a vital nutrient for the vast majority of organisms. Gram-positive bacteria, Gram-negative bacteria and archaea established different strategies to utilize iron from various sources. This article concentrates on the cytoplasmic membrane-associated uptake systems involved in the acquisition of iron. Genetic, biochemical and structural data as well as computational analyses were taken int...

On the Existence, Morphology, Nature, and Functions of the Cytoplasmic Membrane in the Bacterial Cell.

Electron Microscope Observations on the Behavior of the Bacterial Cytoplasmic Membrane During Cellular Division

Bacterial cells were fixed in OsO(4), washed, dehydrated, and embedded in a methacrylate mixture. Ultrathin sections were cut on a Porter-Blum ultramicrotome and were examined in an RCA electron microscope, type EMU-2D. The sections revealed that the cytoplasmic membrane undergoes a centripetal growth to form a membrane septum. This septum is formed as a double structure. Constriction of the da...