coli) and hence is not universally required. However, while FtsA, FtsQLB, FtsI and FtsW are widely conserved, FtsN is limited to Gram-negative organisms (such as E.
![pbp3 ftsi pbp3 ftsi](https://i.ytimg.com/vi/vcwj5ES_GBo/maxresdefault.jpg)
FtsN appears to have several functions: it stabilizes the divisome (at least when over-expressed), acts as a trigger for cytokinesis (via interactions with FtsI and FtsW), and activates FtsA mediated recruitment of FtsQLB through direct binding of FtsA. FtsW is related to the putative elongation-specific transglycosylase RodA, another divisome protein. Both FtsI and FtsW are required for synthesis of the septal wall. After the early proteins, the FtsQLB subcomplex is added, followed by FtsI (transpeptidase), FtsW (transglycosylase), and FtsN. While FtsA and especially FtsZ are highly conserved among bacteria, ZipA, which is a second membrane anchor for FtsZ in gamma-proteobacteria, EzrA, and the Zap proteins are less well conserved and are missing in some species. It starts with the early proteins FtsZ and its membrane anchor FtsA, and the proteins ZipA, EzrA, and the Zaps (ZapA, ZapB, ZapC, ZapD) which promote FtsZ ring-formation. The precise assembly process of the divisome is not well understood. FtsZ assembly appears to be linked to successful DNA replication with MatP and ZapB somehow coordinating interactions between the division machinery and DNA replication during chromosome segregation in E. Bacterial DNA replication is initiated by the binding of DnaA (an ATPase) to the origin of replication (oriC) at midcell. subtilis results in elongated cells without proper cell division. FtsI, also known as PBP3, is the divisome-specific transpeptidase required for synthesis of the division septum.ĭNA replication and cell division ĭNA replication in bacteria is tightly linked to cell division. FtsK and FtsW are larger proteins with multiple transmembrane domains.
![pbp3 ftsi pbp3 ftsi](https://files.rcsb.org/pub/pdb/validation_reports/kg/6kgw/6kgw_multipercentile_validation.png)
FtsA protein binds directly to FtsZ in the cytoplasm, and FtsB, FtsL and FtsQ form an essential membrane-embedded subcomplex. Several other fts genes, such as ftsA, ftsW, ftsQ, ftsI, ftsL, ftsK, ftsN, and ftsB, were all found to be essential for cell division and to associate with the divisome complex and the FtsZ ring. coli with a similar number of proteins in Gram-positive bacteria (such as Bacillus subtilis), although not all proteins are conserved across bacteria. However, more than 20 proteins are known to be part of the divisome in E. The precise composition of the divisome and elongasome remains unknown, given that they are highly dynamic protein complexes which recruit and release certain proteins during cell division. Three breakthroughs came with the discovery of the ftsZ gene in 1980 and the realization that the FtsZ protein was localized to the division plane of dividing cells, and finally the realization that the structure of FtsZ is remarkably similar to tubulin and that they likely share a common ancestor. At the non-permissive temperature (usually 42 ☌), fts mutant cells continue to elongate without dividing, forming filaments that can be up to 150 μ m in wild-type cells).
![pbp3 ftsi pbp3 ftsi](https://cdn.rcsb.org/images/structures/pb/3pbo/3pbo_chain-A.jpeg)
They were called fts genes, because mutants of these genes conferred a filamentous temperature- sensitive phenotype. Some of the first cell-division genes of Escherichia coli were discovered by François Jacob's group in France in the 1960s. 5 The mitochondrial (eukaryotic) divisome.