title: Factors essential for L,D-transpeptidase-mediated peptidoglycan cross-linking and β-lactam resistance inEscherichia coli.
abstract: The target of β-lactam antibiotics is the D,D-transpeptidase activity of penicillin-binding proteins (PBPs) for synthesis of 4→3 cross-links in the peptidoglycan of bacterial cell walls. Unusual 3→3 cross-links formed by L,D-transpeptidases were first detected inEscherichia colimore than four decades ago, however no phenotype has previously been associated with their synthesis. Here we show that production of the L,D-transpeptidase YcbB in combination with elevated synthesis of the (p)ppGpp alarmone by RelA lead to full bypass of the D,D-transpeptidase activity of PBPs and to broad-spectrum β-lactam resistance. Production of YcbB was therefore sufficient to switch the role of (p)ppGpp from antibiotic tolerance to high-level β-lactam resistance. This observation identifies a new mode of peptidoglycan polymerization inE. colithat relies on an unexpectedly small number of enzyme activities comprising the glycosyltransferase activity of class A PBP1b and the D,D-carboxypeptidase activity of DacA in addition to the L,D-transpeptidase activity of YcbB.
authors: INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Sorbonne Universités, UPMC Université Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.
authors: Jean-Emmanuel
authors: JE
authors: Hugonnet
authors: Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France.
authors: Dominique
authors: D
authors: Mengin-Lecreulx
authors: Bacterial Cell Biology and Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands.
authors: Alejandro
authors: A
authors: Monton
authors: Bacterial Cell Biology and Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands.
authors: Tanneke
authors: T
authors: den Blaauwen
authors: INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Sorbonne Universités, UPMC Université Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.
authors: Etienne
authors: E
authors: Carbonnelle
authors: INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Sorbonne Universités, UPMC Université Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.
authors: Carole
authors: C
authors: Veckerlé
authors: Indiana University, Indiana, United States.
authors: Yves V
authors: YV
authors: Brun
authors: Indiana University, Indiana, United States.
authors: Michael
authors: M
authors: van Nieuwenhze
authors: Institut Pasteur, Paris, France.
authors: Christiane
authors: C
authors: Bouchier
authors: INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Sorbonne Universités, UPMC Université Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.
authors: Kuyek
authors: K
authors: Tu
authors: Rhode Island Hospital, Brown University, Providence, United States.
authors: Louis B
authors: LB
authors: Rice
authors: INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Sorbonne Universités, UPMC Université Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France.
authors: Michel
authors: 0000-0003-1007-636X
authors: M
authors: Arthur
mesh_terms: D004926:Escherichia coli / Q000201:enzymology* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D006158:Guanosine Pentaphosphate / Q000378:metabolism; D006159:Guanosine Tetraphosphate / Q000378:metabolism; D008025:Ligases / Q000378:metabolism; D010457:Peptidoglycan / Q000378:metabolism*; D010458:Peptidyl Transferases / Q000378:metabolism*; D018440:beta-Lactam Resistance
chemical_list: D029968:Escherichia coli Proteins; D010457:Peptidoglycan; D006159:Guanosine Tetraphosphate; D006158:Guanosine Pentaphosphate; D010458:Peptidyl Transferases; C000625022:YcbB protein, E coli; D008025:Ligases; C028812:guanosine 3',5'-polyphosphate synthetases
keywords: (p)ppGpp; E. coli; L,D-transpeptidase; PBP1b; PBP5; infectious disease; mecillinam; microbiology; β-lactam