A monomeric StayGold fluorescent protein.

StayGold is an exceptionally bright and stable fluorescent protein that is highly resistant to photobleaching. Despite favorable fluorescence properties, use of StayGold as a fluorescent tag is limited because it forms a natural dimer. Here we report the 1.

Activator-induced conformational changes regulate division-associated peptidoglycan amidases.

AmiA and AmiB are peptidoglycan-hydrolyzing enzymes from  that are required to break the peptidoglycan layer during bacterial cell division and maintain integrity of the cell envelope. In vivo, the activity of AmiA and AmiB is tightly controlled through their interactions with the membrane-bound FtsEX-EnvC complex. Activation of AmiA and AmiB requires access to a groove in the amidase-activating LytM domain of EnvC which is gated by ATP-driven conformational changes in FtsEX-EnvC complex.

Insights into bacterial cell division from a structure of EnvC bound to the FtsX periplasmic domain.

FtsEX is a bacterial ABC transporter that regulates the activity of periplasmic peptidoglycan amidases via its interaction with the murein hydrolase activator, EnvC. In , FtsEX is required to separate daughter cells after cell division and for viability in low-osmolarity media. Both the ATPase activity of FtsEX and its periplasmic interaction with EnvC are required for amidase activation, but the process itself is poorly understood.