Small-molecule-mediated Signalling in Bacteria
Aswin Sai Narain Seshasayee and Nicholas M. Luscombe
from: Bacterial Gene Regulation and Transcriptional Networks (Edited by: M. Madan Babu). Caister Academic Press, U.K. (2013)
The ability to sense and respond to environmental cues is critical to the survival of unicellular organisms like bacteria. An important type of signals is represented by small molecules. In this review, following a general description of the prevalence of small-molecule-binding proteins in the prokaryotic kingdom, we discuss the following aspects of bacterial signalling mediated by small molecules: (a) the interplay between small-molecule signalling and metabolism, which involves local regulation of specific metabolic pathways, in addition to a more global integration of metabolic and other cellular functions; and (b) signal transduction via two second messenger small molecules - ppGpp and c-di-GMP - which initiate stringent response following nutrient starvation, and control switching between motile and adhesive states respectively. In conclusion, we briefly mention two other dimensions of small-molecule signalling: (a) the role of antibiotics in triggering transcriptional responses at sub-inhibitory concentrations; and (b) inter-kingdom signalling between bacteria and their mammalian hosts through hormones and quorum sensing signals read more ...