Disassembly of the divisome in Escherichia coli: evidence that FtsZ dissociates before compartmentalization.

In most bacteria cell division is mediated by a protein super-complex called the divisome that co-ordinates the constriction and scission of the cell envelope. FtsZ is the first of the divisome proteins to accumulate at the division site and is widely thought to function as a force generator that constricts the cell envelope. In this study we have used a combination of confocal fluorescence microscopy and fluorescence recovery after photobleaching (FRAP) to determine if divisome proteins are present at the septum at the time of cytoplasmic compartmentalization in Escherichia coli.

Mesenteric infarction due to iatrogenic polycythemia.

Background: Polycythemia vera is defined as a chronic myeloproliferative disorder characterized by increased red blood cell count. There have been no reports on mesenteric thrombosis resulting from iatrogenic polycythemia.

Methods: We present a patient with a history of non-small cell lung cancer undergoing maintenance oral chemotherapy on tarceva and adjunctive use of procrit.

The Escherichia coli cell division protein ZipA forms homodimers prior to association with FtsZ.

ZipA is an essential component of the cell division machinery in E. coli and other closely related bacteria. It is an integral membrane protein that binds to FtsZ, tethering it to the inner membrane.

Sequential closure of the cytoplasm and then the periplasm during cell division in Escherichia coli.

To visualize the latter stages of cell division in live Escherichia coli, we have carried out fluorescence recovery after photobleaching (FRAP) on 121 cells expressing cytoplasmic green fluorescent protein and periplasmic mCherry. Our data show conclusively that the cytoplasm is sealed prior to the periplasm during the division event.

Penicillin-binding protein 5 can form a homo-oligomeric complex in the inner membrane of Escherichia coli.

Penicillin-binding protein 5 (PBP5) is a DD-carboxypeptidase, which cleaves the terminal D-alanine from the muramyl pentapeptide in the peptidoglycan layer of Escherichia coli and other bacteria. In doing so, it varies the substrates for transpeptidation and plays a key role in maintaining cell shape. In this study, we have analyzed the oligomeric state of PBP5 in detergent and in its native environment, the inner membrane.