Cava, FelipeLam, Hubertde Pedro, Miguel A.Waldor, Matthew2011-12-062010Cava, Felipe, Hubert Lam, Miguel A. de Pedro, and Matthew K. Waldor. 2010. Emerging knowledge of regulatory roles of D-amino acids in bacteria. Cellular and Molecular Life Sciences 68(5): 817-831.1420-682Xhttp://nrs.harvard.edu/urn-3:HUL.InstRepos:5360625The D-enantiomers of amino acids have been thought to have relatively minor functions in biological processes. While L-amino acids clearly predominate in nature, D-amino acids are sometimes found in proteins that are not synthesized by ribosomes, and D-Ala and D-Glu are routinely found in the peptidoglycan cell wall of bacteria. Here, we review recent findings showing that D-amino acids have previously unappreciated regulatory roles in the bacterial kingdom. Many diverse bacterial phyla synthesize and release D-amino acids, including D-Met and D-Leu, which were not previously known to be made. These noncanonical D-amino acids regulate cell wall remodeling in stationary phase and cause biofilm dispersal in aging bacterial communities. Elucidating the mechanisms by which D-amino acids govern cell wall remodeling and biofilm disassembly will undoubtedly reveal new paradigms for understanding how extracytoplasmic processes are regulated as well as lead to development of novel therapeutics.en-USracemasestationary phasepeptidoglycanbiofilmregulationD-amino acidJournal Article2011-12-0610.1007/s00018-010-0571-8