title: Mycobacterium aviumsubsp.paratuberculosis (Map)Fatty Acids Profile Is Strain-Dependent and Changes Upon Host Macrophages Infection.
abstract: Johne's disease is a chronic granulomatous enteritis of ruminants caused by the intracellular bacteriumMycobacterium aviumsubsp.paratuberculosis(Map). We previously demonstrated thatMapisolates from sheep persisted within host macrophages in lower CFUs than cattle isolates after 7 days of infection. In the current study, we hypothesize that these phenotypic differences betweenMapisolates may be driven be the fatty acids (FAs) present on the phosphadidyl-1-myo-inositol mannosides of theMapcell wall that mediate recognition by the mannose receptors of host macrophages. FAs modifications may influenceMap's envelope fluidity ultimately affecting pathogenicity. To test this hypothesis, we investigated the responses of twoMapisolates from cattle (K10 isolate) and sheep (2349/06-1) to the bovine and ovine macrophage environment by measuring the FAs content of extracellular and intracellular bacteria. For this purpose, macrophages cell lines of bovine (BOMAC) and ovine (MOCL-4) origin were infected with the two isolates ofMapfor 4 days at 37°C. The relative FAs composition of the two isolates recovered from infected BOMAC and MOCL-4 cells was determined by gas chromatography and compared with that of extracellular bacteria and that of bacteria grown in Middlebrook 7H9 medium. Using this approach, we demonstrated that the FAs composition of extracellular and 7H9-grown bacteria was highly conserved within eachMapisolate, and statistically different from that of intracellular bacteria. Analysis of FAs composition from extracellular bacteria enabled the distinction of the twoMapstrains based on the presence of the tuberculostearic acid (18:0 10Me) exclusively in the K10 strain ofMap. In addition, significant differences in the content of Palmitic acid and cis-7 Palmitoleic acid between both isolates harvested from the extracellular environment were observed. Once the infection established itself in BOMAC and MOCL-4 cells, the FAs profiles of bothMapisolates appeared conserved. Our results suggest that the FAs composition ofMapmight influence its recognition by macrophages and influence the survival of the bacillus within host macrophages.
authors.affiliation: Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Technological Park of Bizkaia Derio, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Alonso-Hearn
authors.affiliation: Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Technological Park of Bizkaia Derio, Spain.
authors.forename: Naiara
authors.initials: N
authors.lastname: Abendaño
authors.affiliation: Spanish Type Culture Collection (CECT), University of Valencia, Parc Científic Universitat de València Paterna, Spain.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Ruvira
authors.affiliation: Spanish Type Culture Collection (CECT), University of Valencia, Parc Científic Universitat de València Paterna, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Aznar
authors.affiliation: Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago Santiago de Compostela, Spain.
authors.forename: Mariana
authors.initials: M
authors.lastname: Landin
authors.affiliation: Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Technological Park of BizkaiaDerio, Spain; Servicio Regional de Investigación y Desarrollo Agroalimentario, Agri-Food Research and Development Regional ServiceVillaviciosa, Spain.
authors.forename: Ramon A
authors.initials: RA
authors.lastname: Juste
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D002473:Cell Wall / Q000737:chemistry*; D002849:Chromatography, Gas; D005227:Fatty Acids / Q000032:analysis*; D054884:Host-Pathogen Interactions; D008264:Macrophages / Q000382:microbiology*; D050296:Microbial Viability; D016927:Mycobacterium avium subsp. paratuberculosis / Q000737:chemistry* / Q000302:isolation & purification; D012756:Sheep
chemical_list: D005227:Fatty Acids
keywords: Map-host interaction; Mycobacterium avium subp. paratuberculosis; fatty acids; lipid metabolism; macrophages