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Within the last fifteen years, scientists have discovered that most groups of bacteria use a rich chemical lexicon to send and receive signals from other bacteria. Bacteria use these signals to coordinate a wide range of activities, including bioluminescence, sporulation, biofilm formation, horizontal DNA transfer, population density estimates, and pathogenesis. Understanding this communication will be crucial for future research in bacterial physiology, ecology, and bacterial disease. It may also be useful in intervening in bacterial processes, both harmful and beneficial.

This new volume of thirty chapters brings together the latest findings on chemical communication among bacteria and points towards potential areas for future research. Organized into four sections, this volume addresses: cell-cell signaling during development and DNA exchange; signaling in relationship to humans, animals, and plants; production and detection of chemical signals; and eukaryotic quorum sensing. Important new discoveries addressed include the structures of three bacterial signal synthases, signal receptors, mechanisms of signal transduction, pathways, and the expression of target genes.

Leading researchers in various aspects of bacterial signaling have contributed to this volume and provide a comprehensive overview of signal synthesis, detection, and its impacts on bacterial behavior. This indispensable book will be necessary reading for any microbiologist looking for a wide-ranging reference book on cell-cell signaling.

Hardcover, 483 pages, illustrations, index.

The marine animal pathogen Vibrio harveyi and the human pathogen Vibrio cholerae are aquatic bacteria that engage in a process of cell-cell communication called quorum sensing (QS). Autoinducer (AI)-2 is derived from S-adenosylmethionine in three enzymatic steps. First, S-adenosylmethionine serves as a methyl donor for many biochemical processes, and these methyltransferase-dependent reactions yield S-adenosylhomocysteine. Second, S-adenosylhomocysteine is metabolized to adenine and S-ribosylhomocysteine by the enzyme Pfs, and third, S-ribosylhomocysteine is the substrate for the LuxS enzyme. In mixed species consortia, other microbes also have the potential to alter AI-2 levels, and other classes of AIs are clearly manipulated, but the authors have restricted the discussion to AI-2 and how that pertains to Vibrio QS. Appropriate and distinct responses to potentially different communities are possible because of signal integration in the Vibrio circuits. Channel proteins LsrC and LsrD mediate the delivery of the ligand across the membrane. LsrA is an ATPase that supplies the energy required for transport. Rapid Lsr-dependent transport of R-THMF into the cell occurs at high cell densities. Recent studies in V. harveyi show that it possesses five qrr genes, like its closest Vibrio relatives. Examination of their functions reveals that, in stark contrast to V. cholerae, in V. harveyi the quorum-regulatory RNAs (Qrr) sRNAs act additively to control luxR mRNA levels.

Earlier this year, the Office of Science and Technology Policy (OSTP) issued a call for input on a proposed “National Bioeconomy Blueprint.” The blueprint, released in January 2012, details “Administration-wide steps to harness biological research innovations to address national challenges in health, food, energy, and the environment.” ASM took the opportunity to respond to the OSTP's request for comment by describing the many ways that the field of microbiology can help the nation reach the blueprint's goals. An excerpt from ASM's response follows––the full response can be found at http://www.asm.org/index.php/what-s-new-in-public-policy/bioec-12-11.html.