Molecular and Cell Biological Analysis of SwrB in Bacillus subtilis.

Swarming motility is flagellum-mediated movement over a solid surface, and Bacillus subtilis cells require an increase in flagellar density to swarm. SwrB is a protein of unknown function required for swarming that is necessary to increase the number of flagellar hooks but not basal bodies. Previous work suggested that SwrB activates flagellar type III secretion, but the mechanism by which it might perform this function is unknown.

Use of the wide-awake local anaesthetic no tourniquet in the management of distal radius fractures.

Objective: To evaluate the Wide-Awake Local Anaesthesia with No Tourniquet (WALANT) method in fixation of distal radial fractures.

Methods: Forty patients admitted to the Jinnah Postgraduate Medical Centre, Karachi, Pakistan were recruited from March 2017 to December 2018. All patients had a distal radial fracture which was appropriate for internal fixation with a locked volar distal radial plate.

Functional Activation of the Flagellar Type III Secretion Export Apparatus.

Flagella are assembled sequentially from the inside-out with morphogenetic checkpoints that enforce the temporal order of subunit addition. Here we show that flagellar basal bodies fail to proceed to hook assembly at high frequency in the absence of the monotopic protein SwrB of Bacillus subtilis. Genetic suppressor analysis indicates that SwrB activates the flagellar type III secretion export apparatus by the membrane protein FliP.

SlrA/SinR/SlrR inhibits motility gene expression upstream of a hypersensitive and hysteretic switch at the level of σ(D) in Bacillus subtilis.

Exponentially growing Bacillus subtilis cultures are epigenetically differentiated into two subpopulations in which cells are either ON or OFF for σ(d) -dependent gene expression: a pattern suggestive of bistability. The gene encoding σ(D) , sigD, is part of the 31-gene fla/che operon where its location at the 3' end, 25 kb away from the strong P(fla/che) promoter, determines its expression level relative to a threshold. Here we show that addition of a single extra copy of the slrA gene in the chromosome inhibited σ(d) -dependent gene expression.