New Cell Division Protein in Escherichia coli
Bacterial cell division is accomplished by proteins with two defining characteristics: they localize to the midcell, and their mutants stall division. Jorgenson and Young (e00046-18) present evidence for a new cell division protein in Escherichia coli, YtfB. YtfB is recruited to midcell during the early stages of septation, and a ytfB mutant exacerbates the division defect of cells lacking DedD, a separate division protein. Although a LysM-like OapA domain derived from YtfB binds to peptidoglycan and directs fusion proteins to the wall at midcell, the domain is not necessary for localizing full-length YtfB.
Efflux Pumps of Acinetobacter baumannii Have Distinct Substrate Specificities
Efflux pumps play a critical role in development and spread of multidrug-resistant clinical isolates of Acinetobacter baumannii. However, their specific contribution to resistance is difficult to extract due to complex interplays with the outer membrane barrier and drug-modifying enzymes. Leus et al. (e00049-18) analyzed substrate specificities and efficiencies of efflux pumps separated from other mechanisms. Surprisingly, A. baumannii efflux pumps have distinct substrate specificities and are effective against only a few antibiotics. Other antibiotics, such as aminoglycosides, are not directly affected by efflux pumps. For such antibiotics, efflux pumps are required but not sufficient to provide clinical resistance.
- Copyright © 2018 American Society for Microbiology.
