title: A novel mycolic acid species defines two novel genera of the Actinobacteria, Hoyosella and Amycolicicoccus.
abstract: Corynebacterineae are characterized by the presence of long-chain lipids, notably mycolic acids (α-alkyl, β-hydroxy fatty acids), the structures of which are genus-specific. Mycolic acids from two environmental strains, Amycolicicoccus subflavus and Hoyosella altamirensis, were isolated and their structures were established using a combination of mass spectrometry analysis, (1)H-NMR spectroscopy and chemical degradations. The C(2)-C(3) cleavage of these C(30)-C(36) acids led to the formation of two fragments: saturated C(9)-C(11) acids, and saturated and unsaturated C(20)-C(25) aldehydes. Surprisingly, the fatty acids at the origin of the two fragments making up these mycolic acids were present in only minute amounts in the fatty acid pool. Moreover, the double bond in the main C(24) aldehyde fragment was located at position ω16, whereas that found in the ethylenic fatty acids of the bacteria was at ω9. These data question the biosynthesis of these new mycolic acids in terms of the nature of the precursors, chain elongation and desaturation. Nevertheless, they are consistent with the occurrence of the key genes of mycolic acid biosynthesis, including those encoding proteins of the fatty acid synthase II system, identified in the genome of A. subflavus. Altogether, while the presence of mycolic acids and analysis of their 16S rDNA sequences would suggest that these strains belong to the Mycobacteriaceae family, the originality of their structures reinforces the recent description of the novel genera Amycolicicoccus and Hoyosella.
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Marie-Antoinette
authors.initials: MA
authors.lastname: Lanéelle
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Launay
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Lucie
authors.initials: L
authors.lastname: Spina
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Hedia
authors.initials: H
authors.lastname: Marrakchi
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Laval
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Eynard
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Lemassu
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Maryelle
authors.initials: M
authors.lastname: Tropis
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Mamadou
authors.initials: M
authors.lastname: Daffé
authors.affiliation: Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.|Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Etienne
mesh_terms: D000192:Actinomycetales / Q000737:chemistry* / Q000145:classification* / Q000302:isolation & purification; D053898:Biosynthetic Pathways / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004783:Environmental Microbiology; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009171:Mycolic Acids / Q000032:analysis* / Q000737:chemistry; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009171:Mycolic Acids; D012336:RNA, Ribosomal, 16S