title: The nonredundant roles of two 4'-phosphopantetheinyl transferases in vital processes of Mycobacteria.
abstract: Mycobacterium tuberculosis contains >20 enzymes that require activation by transfer of the 4'-phosphopantetheine moiety of CoA onto a conserved serine residue, a posttranslational modification catalyzed by 4'-phosphopantetheinyl transferases (PPTases). The modified proteins are involved in key metabolic processes such as cell envelope biogenesis and the production of virulence factors. We show that two PPTases conserved in all Mycobacterium spp. and in related genera activate two different subsets of proteins and are not functionally redundant. One enzyme, AcpS, activates the two fatty acid synthase systems of mycobacteria, whereas the other PPTase, PptT, acts on type-I polyketide synthases and nonribosomal peptide synthases, both of which are involved in the biosynthesis of virulence factors. We demonstrate that both PPTases are essential for Mycobacterium smegmatis viability and that PptT is required for the survival of Mycobacterium bovis bacillus Calmette-Guérin. These enzymes are thus central to the biology of mycobacteria and for mycobacterial pathogenesis and represent promising targets for new antituberculosis drugs.
authors.affiliation: Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique and Université P. Sabatier (Unité Mixte de Recherche 5089), 205 Route de Narbonne, 31077 Toulouse Cedex, France. christian.chalut@ipbs.fr
authors.forename: Christian
authors.initials: C
authors.lastname: Chalut
authors.forename: Laure
authors.initials: L
authors.lastname: Botella
authors.forename: Célia
authors.initials: C
authors.lastname: de Sousa-D'Auria
authors.forename: Christine
authors.initials: C
authors.lastname: Houssin
authors.forename: Christophe
authors.initials: C
authors.lastname: Guilhot
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002384:Catalysis; D015169:Colony Count, Microbial; D048230:Corynebacterium glutamicum / Q000235:genetics / Q000378:metabolism; D005227:Fatty Acids / Q000096:biosynthesis; D050296:Microbial Viability; D015394:Molecular Structure; D009161:Mycobacterium / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D010641:Phenotype; D017855:Transferases (Other Substituted Phosphate Groups) / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D005227:Fatty Acids; C082662:phosphopantetheinyl transferase; D017855:Transferases (Other Substituted Phosphate Groups)