title: Drosophila melanogaster is a genetically tractable model host for Mycobacterium marinum.
abstract: Mycobacterium marinum is a pathogenic mycobacterial species that is closely related to Mycobacterium tuberculosis and causes tuberculosis-like disease in fish and frogs. We infected the fruit fly Drosophila melanogaster with M. marinum. This bacterium caused a lethal infection in the fly, with a 50% lethal dose (LD(50)) of 5 CFU. Death was accompanied by widespread tissue damage. M. marinum initially proliferated inside the phagocytes of the fly; later in infection, bacteria were found both inside and outside host cells. Intracellular M. marinum blocked vacuolar acidification and failed to colocalize with dead Escherichia coli, similar to infections of mouse macrophages. M. marinum lacking the mag24 gene were less virulent, as determined both by LD(50) and by death kinetics. Finally, in contrast to all other bacteria examined, mycobacteria failed to elicit the production of antimicrobial peptides in Drosophila.We believe that this system should be a useful genetically tractable model for mycobacterial infection.
authors.affiliation: Department of Microbiology and Immunology, Stanford University School of Medicine, California 94305, USA.
authors.forename: Marc S
authors.initials: MS
authors.lastname: Dionne
authors.forename: Nafisa
authors.initials: N
authors.lastname: Ghori
authors.forename: David S
authors.initials: DS
authors.lastname: Schneider
mesh_terms: D000818:Animals; D017209:Apoptosis; D029721:Drosophila Proteins / Q000502:physiology; D004331:Drosophila melanogaster / Q000382:microbiology*; D006434:Hemocytes / Q000382:microbiology; D019476:Insect Proteins / Q000096:biosynthesis; D007928:Lethal Dose 50; D008264:Macrophages / Q000276:immunology; D023421:Models, Animal; D019910:Mycobacterium marinum / Q000276:immunology / Q000472:pathogenicity*; D010586:Phagocytes / Q000276:immunology; D010587:Phagocytosis; D011956:Receptors, Cell Surface / Q000502:physiology; D051193:Toll-Like Receptors; D014617:Vacuoles / Q000378:metabolism; D014774:Virulence
chemical_list: C488990:AttA protein, Drosophila; C488991:AttB protein, Drosophila; C488989:AttC protein, Drosophila; D029721:Drosophila Proteins; D019476:Insect Proteins; D011956:Receptors, Cell Surface; C068721:Tl protein, Drosophila; D051193:Toll-Like Receptors; C039711:attacin antibacterial protein, insect; C439909:imd protein, Drosophila