title: Characterization of an acetyltransferase that detoxifies aromatic chemicals in Legionella pneumophila.
abstract: Legionella pneumophila is an opportunistic pathogen and the causative agent of Legionnaires' disease. Despite being exposed to many chemical compounds in its natural and man-made habitats (natural aquatic biotopes and man-made water systems), L. pneumophila is able to adapt and survive in these environments. The molecular mechanisms by which this bacterium detoxifies these chemicals remain poorly understood. In particular, the expression and functions of XMEs (xenobiotic-metabolizing enzymes) that could contribute to chemical detoxification in L. pneumophila have been poorly documented at the molecular and functional levels. In the present paper we report the identification and biochemical and functional characterization of a unique acetyltransferase that metabolizes aromatic amine chemicals in three characterized clinical strains of L. pneumophila (Paris, Lens and Philadelphia). Strain-specific sequence variations in this enzyme, an atypical member of the arylamine N-acetyltransferase family (EC 2.3.1.5), produce enzymatic variants with different structural and catalytic properties. Functional inactivation and complementation experiments showed that this acetyltransferase allows L. pneumophila to detoxify aromatic amine chemicals and grow in their presence. The present study provides a new enzymatic mechanism by which the opportunistic pathogen L. pneumophila biotransforms and detoxifies toxic aromatic chemicals. These data also emphasize the role of XMEs in the environmental adaptation of certain prokaryotes.
authors.affiliation: Université Paris Diderot, Sorbonne Paris Cité, Unité de Biologie Fonctionnelle et Adaptative, CNRS EAC4413, 75013, Paris, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Kubiak
authors.forename: Delphine
authors.initials: D
authors.lastname: Dervins-Ravault
authors.forename: Benjamin
authors.initials: B
authors.lastname: Pluvinage
authors.forename: Alain F
authors.initials: AF
authors.lastname: Chaffotte
authors.forename: Laura
authors.initials: L
authors.lastname: Gomez-Valero
authors.forename: Julien
authors.initials: J
authors.lastname: Dairou
authors.forename: Florent
authors.initials: F
authors.lastname: Busi
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Dupret
authors.forename: Carmen
authors.initials: C
authors.lastname: Buchrieser
authors.forename: Fernando
authors.initials: F
authors.lastname: Rodrigues-Lima
mesh_terms: D000588:Amines / Q000378:metabolism*; D001191:Arylamine N-Acetyltransferase / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D002942:Circular Dichroism; D005816:Genetic Complementation Test; D014644:Genetic Variation; D006841:Hydrocarbons, Aromatic / Q000378:metabolism*; D008658:Inactivation, Metabolic; D016952:Legionella pneumophila / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D007877:Legionnaires' Disease / Q000235:genetics / Q000382:microbiology; D010802:Phylogeny; D017510:Protein Folding; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D000588:Amines; D006841:Hydrocarbons, Aromatic; D011994:Recombinant Proteins; D001191:Arylamine N-Acetyltransferase