Small molecule communication of : the ins and outs of autoinducer and nitric oxide signaling.

SUMMARY is a Gram-negative environmental bacterium, which survives in planktonic form, colonizes biofilms, and infects protozoa. Upon inhalation of -contaminated aerosols, the opportunistic pathogen replicates within and destroys alveolar macrophages, thereby causing a severe pneumonia termed Legionnaires' disease. Gram-negative bacteria employ low molecular weight organic compounds as well as the inorganic gas nitric oxide (NO) for cell-cell communication.

Nitric oxide signaling through three receptors regulates virulence, biofilm formation, and phenotypic heterogeneity of .

Unlabelled: The causative agent of Legionnaires' disease, , is an environmental bacterium, that replicates in macrophages, parasitizes amoeba, and forms biofilms. employs the quorum sensing (Lqs) system and the transcription factor LvbR to control various bacterial traits, including virulence and biofilm architecture. LvbR negatively regulates the nitric oxide (NO) receptor Hnox1, linking quorum sensing to NO signaling.

Migration of Acanthamoeba through Legionella biofilms is regulated by the bacterial Lqs-LvbR network, effector proteins and the flagellum.

The environmental bacterium Legionella pneumophila causes the pneumonia Legionnaires' disease. The opportunistic pathogen forms biofilms and employs the Icm/Dot type IV secretion system (T4SS) to replicate in amoebae and macrophages. A regulatory network comprising the Legionella quorum sensing (Lqs) system and the transcription factor LvbR controls bacterial motility, virulence and biofilm architecture.

Systematic exploration of Escherichia coli phage-host interactions with the BASEL phage collection.

Bacteriophages, the viruses infecting bacteria, hold great potential for the treatment of multidrug-resistant bacterial infections and other applications due to their unparalleled diversity and recent breakthroughs in their genetic engineering. However, fundamental knowledge of the molecular mechanisms underlying phage-host interactions is mostly confined to a few traditional model systems and did not keep pace with the recent massive expansion of the field. The true potential of molecular biology encoded by these viruses has therefore remained largely untapped, and phages for therapy or other applications are often still selected empirically.