title: Role of unusual P loop ejection and autophosphorylation in HipA-mediated persistence and multidrug tolerance.
abstract: HipA is a bacterial serine/threonine protein kinase that phosphorylates targets, bringing about persistence and multidrug tolerance. Autophosphorylation of residue Ser150 is a critical regulatory mechanism of HipA function. Intriguingly, Ser150 is not located on the activation loop, as are other kinases; instead, it is in the protein core, where it forms part of the ATP-binding "P loop motif." How this buried residue is phosphorylated and regulates kinase activity is unclear. Here, we report multiple structures that reveal the P loop motif's exhibition of a remarkable "in-out" conformational equilibrium, which allows access to Ser150 and its intermolecular autophosphorylation. Phosphorylated Ser150 stabilizes the "out state," which inactivates the kinase by disrupting the ATP-binding pocket. Thus, our data reveal a mechanism of protein kinase regulation that is vital for multidrug tolerance and persistence, as kinase inactivation provides the critical first step in allowing dormant cells to revert to the growth phenotype and to reinfect the host.
authors.affiliation: Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA. maria.schumacher@duke.edu
authors.forename: Maria A
authors.initials: MA
authors.lastname: Schumacher
authors.forename: JungKi
authors.initials: J
authors.lastname: Min
authors.forename: Todd M
authors.initials: TM
authors.lastname: Link
authors.forename: Ziqiang
authors.initials: Z
authors.lastname: Guan
authors.forename: Weijun
authors.initials: W
authors.lastname: Xu
authors.forename: Young-Ho
authors.initials: YH
authors.lastname: Ahn
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Soderblom
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Kurie
authors.forename: Artem
authors.initials: A
authors.lastname: Evdokimov
authors.forename: M Arthur
authors.initials: MA
authors.lastname: Moseley
authors.forename: Kim
authors.initials: K
authors.lastname: Lewis
authors.forename: Richard G
authors.initials: RG
authors.lastname: Brennan
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism; D020816:Amino Acid Motifs; D024901:Drug Resistance, Multiple, Bacterial / Q000502:physiology*; D004926:Escherichia coli / Q000737:chemistry / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D010766:Phosphorylation / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry* / Q000378:metabolism; D012694:Serine / Q000737:chemistry / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; C070741:hipA protein, E coli; D012694:Serine; D000255:Adenosine Triphosphate; D017346:Protein Serine-Threonine Kinases