title: Emerging knowledge of regulatory roles of D-amino acids in bacteria.
abstract: The 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.
authors.affiliation: Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, and Howard Hughes Medical Institute, Boston, MA 02115, USA. fcava@rics.bwh.harvard.edu
authors.forename: Felipe
authors.initials: F
authors.lastname: Cava
authors.forename: Hubert
authors.initials: H
authors.lastname: Lam
authors.forename: Miguel A
authors.initials: MA
authors.lastname: de Pedro
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Waldor
mesh_terms: D000591:Amino Acid Isomerases / Q000502:physiology; D000596:Amino Acids / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology*; D001419:Bacteria / Q000378:metabolism*; D018441:Biofilms; D002473:Cell Wall / Q000378:metabolism; D008954:Models, Biological; D010457:Peptidoglycan / Q000737:chemistry; D013171:Spores, Bacterial / Q000378:metabolism
chemical_list: D000596:Amino Acids; D010457:Peptidoglycan; D000591:Amino Acid Isomerases