RT Journal Article
SR Electronic
T1 Pal stabilises the bacterial outer membrane during constriction by a mobilisation-and-capture mechanism
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 790931
DO 10.1101/790931
A1 Joanna Szczepaniak
A1 Peter Holmes
A1 Karthik Rajasekar
A1 Renata Kaminska
A1 Firdaus Samsudin
A1 Patrick George Inns
A1 Patrice Rassam
A1 Syma Khalid
A1 Seán M. Murray
A1 Christina Redfield
A1 Colin Kleanthous
YR 2019
UL http://biorxiv.org/content/early/2019/10/04/790931.abstract
AB Coordination of outer membrane constriction with septation is critical to faithful division in Gram-negative bacteria and vital to the barrier function of the membrane. Recent studies suggest this coordination is through the active accumulation of the peptidoglycan-binding outer membrane lipoprotein Pal at division sites by the Tol system, but the mechanism is unknown. Here, we show that Pal accumulation at Escherichia coli division sites is a consequence of three key functions of the Tol system. First, Tol mobilises Pal molecules in dividing cells, which otherwise diffuse very slowly due to their binding of the cell wall. Second, Tol actively captures mobilised Pal molecules and deposits them at the division septum. Third, the active capture mechanism is analogous to that used by the inner membrane protein TonB to dislodge the plug domains of outer membrane TonB-dependent nutrient transporters. We conclude that outer membrane constriction is coordinated with cell division by active mobilisation-and-capture of Pal at division septa by the Tol system.