Min System

The Min System is a mechanism composed of three proteins MinC, MinD, and MinE used by E. coli as a means of properly localizing the septum prior to cell division.

First identified as E. coli mutants that could not produce a properly localized septum, resulting in the generation of minicells[1][2] due to mislocalized cell division occurring near the bacterial poles.

This caused miniature vesicles to pinch off, void of essential molecular constituents permitting it to exist as a viable bacterial cell.

[7] MinD requires a nucleotide exchange step to re-bind to ATP so that it can re-associate with the membrane after MinE release.

In vivo observations show that the oscillation of Min proteins between cell poles occurs approximately every 50 seconds.

[14] Importantly, MinD and MinE can self-organize into a wide variety of patterns depending on the reaction conditions.

[15][16] Additional study is required to elucidate the extent of temporal and spatial signaling permissible by this biological function.

Displacement of the Z-ring and the Ter macrodomain in a long ΔslmA Δmin double mutant E. coli cell. Z-ring fluorescence is followed using a ZipA-GFP construct (green), while the chromosomal terminus is labeled with MatP-mCherry (red). A phase contrast image (gray) is overlaid to visualize the cell contour. The scale bar is 2 μm.
The MinCDE system. MinD-ATP binds to a cell pole, also binds MinC, which prevents the formation of FtsZ polymers. The MinE ring causes hydrolysis of MinD's bound ATP, turning it into ADP and releasing the complex from the membrane. The system oscillates as each pole builds up a concentration of inhibitor that is periodically dismantled.
MinD (cyan) chased by MinE (magenta) to form spiraling waves on an artificial membrane