What bacteria want

Abstract

Bacterial signal transduction systems are responsible for sensing environmental cues and adjusting the cellular behaviour and/or metabolism in response to these cues. They also monitor the intracellular conditions and the status of the cell envelope and the cytoplasmic membrane and trigger various stress responses to counteract adverse changes. This surveillance involves several classes of sensor proteins: histidine kinases; chemoreceptors; membrane components of the sugar phosphotransferase system; adenylate, diadenylate and diguanylate cyclases and certain cAMP, c-di-AMP and c-di-GMP phosphodiesterases; extracytoplasmic function sigma factors and Ser/Thr/Tyr protein kinases and phosphoprotein phosphatases. We have compiled a detailed listing of sensor proteins that are encoded in the genomes of Escherichia coli, Bacillus subtilis and 10 widespread pathogens: Chlamydia trachomatis, Haemophilus influenzae, Helicobacter pylori, Mycobacterium tuberculosis, Mycoplasma pneumoniae, Neisseria gonorrhoeae, Porphyromonas gingivalis, Rickettsia typhi, Streptococcus pyogenes and Treponema pallidum, and checked what, if anything, is known about their functions. This listing shows significant gaps in the understanding of which environmental and intracellular cues are perceived by these bacteria and which cellular responses are triggered by the changes in the respective parameters. A better understanding of bacterial preferences may suggest new ways to modulate the expression of virulence factors and therefore decrease the reliance on antibiotics to fight infection.

Thriving in Wetlands: Ecophysiology of the Spiral-Shaped Methanotroph Methylospira mobilis as Revealed by the Complete Genome Sequence

“…These respond to intracellular signals by synthesizing the second messenger c-di-GMP. Cyclic di-GMP has been shown to regulate a variety of systems, including motility, protein and polysaccharide secretion, cell division and biofilm formation, and intracellular signals [63,64].…”

“…The genome of strains Shm1 encodes 39 diguanylate cyclases (proteins with the conserved GGDEF domain) that respond to environmental or intracellular signals by synthesizing the second messenger c-di-GMP [63,64]. A total of 30 c-di-GMP-specific phosphodiesterases (EAL and HD-GYP domains) that affect a variety of c-di-GMP-regulated systems were also identified.…”

Two forms of phosphomannomutase in gammaproteobacteria: The overlooked membrane-bound form of AlgC is required for twitching motility ofLysobacter enzymogenes

“…subtilis sporulation kinase KinD remains to be identified. If so, two-domain PMMs would offer yet another example of a sensory system that regulates bacterial metabolism in response to environmental cues (Galperin, 2004, 2018). Environmental regulation of the PMM/PGM activity would seem justified, based on the unique position of this enzyme as a common step in peptidoglycan, lipopolysaccharide, and exopolysaccharide biosynthesis pathways.…”

Crowd Controlled—Host Quorum Sensing Drives Phage Decision

“…In order to optimize survival and reproduction, bacteria extensively monitor intracellular conditions as well as the extracellular environment and adjust their behavior and metabolism accordingly (Galperin, 2018). Critical parameters of the surrounding environment are the density and the composition of the local microbial community.…”