title: SacPox from the thermoacidophilic crenarchaeon Sulfolobus acidocaldarius is a proficient lactonase.
abstract: BACKGROUND
  SacPox, an enzyme from the extremophilic crenarchaeal Sulfolobus acidocaldarius (Sac), was isolated by virtue of its phosphotriesterase (or paraoxonase; Pox) activity, i.e. its ability to hydrolyze the neurotoxic organophosphorus insecticides. Later on, SacPox was shown to belong to the Phosphotriesterase-Like Lactonase family that comprises natural lactonases, possibly involved in quorum sensing, and endowed with promiscuous, phosphotriesterase activity.
  
  
  RESULTS
  Here, we present a comprehensive and broad enzymatic characterization of the natural lactonase and promiscuous organophosphorus hydrolase activities of SacPox, as well as a structural analysis using a model.
  
  
  CONCLUSIONS
  Kinetic experiments show that SacPox is a proficient lactonase, including at room temperature. Moreover, we discuss the observed differences in substrate specificity between SacPox and its closest homologues SsoPox and SisLac together with the possible structural causes for these observations.
authors.forename: Janek
authors.initials: J
authors.lastname: Bzdrenga
authors.forename: Julien
authors.initials: J
authors.lastname: Hiblot
authors.forename: Guillaume
authors.initials: G
authors.lastname: Gotthard
authors.forename: Charlotte
authors.initials: C
authors.lastname: Champion
authors.affiliation: URMITE UMR CNRS-IRD 6236, IFR48, Faculté de Médecine et de Pharmacie, Université de la Méditerranée, Marseille, France. mikael.elias@gmx.fr.
authors.forename: Mikael
authors.initials: M
authors.lastname: Elias
authors.forename: Eric
authors.initials: E
authors.lastname: Chabriere
mesh_terms: D000595:Amino Acid Sequence; D007700:Kinetics; D008969:Molecular Sequence Data; D044345:Phosphoric Triester Hydrolases / Q000737:chemistry / Q000378:metabolism*; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D016945:Sulfolobus acidocaldarius / Q000201:enzymology*
chemical_list: D044345:Phosphoric Triester Hydrolases