title: A rapid screening assay for identifying mycobacteria targeted nanoparticle antibiotics.
abstract: Antibiotic resistance is a serious problem. Nanotechnology offers enormous potential in medicine, yet there is limited knowledge regarding the toxicity of nanoparticles (NP) for mycobacterial species that cause serious human diseases (e.g. tuberculosis (TB) and leprosy). Mycobacterial diseases are a major global health problem; TB caused by Mycobacterium tuberculosis (Mtb) kills up to 2 million people annually and there are over 200 000 leprosy cases each year caused by Mycobacterium leprae (M. leprae). Few drugs are effective against these mycobacteria and increasing antibiotic resistance exacerbates the problem. As such, alternative therapies are urgently needed but most current assays used to assess the effectiveness of therapeutics against mycobacteria are slow and expensive. This study aimed to develop a rapid, low-cost assay which can be used for screening the antimicrobial properties of compounds against pathogenic mycobacteria and to assess the toxicity of three NP (silver [Ag], copper oxide [Cu(II)O], and zinc oxide [ZnO]) against a green fluorescent protein reporter strain of Mycobacterium avium subspecies paratuberculosis, a slow growing, pathogenic mycobacterial species causing paratuberculosis in ruminants. Fluorescence was used to monitor mycobacterial growth over time, with NP concentrations of 6.25-100 μg/mL tested for up to 7 days, and a method of data analysis was designed to permit comparison between results. Mycobacterial sensitivity to the NP was found to be NP composition specific and toxicity could be ranked in the following order: Ag > Cu(II)O > ZnO.
authors.affiliation: a Moredun Research Institute, Pentlands Science Park , Penicuik , UK .|b School of Life Sciences, Heriot Watt University , Edinburgh , UK , and.
authors.forename: Samantha
authors.initials: S
authors.lastname: Donnellan
authors.affiliation: c Institute of Occupational Medicine , Edinburgh , UK.
authors.forename: Lang
authors.initials: L
authors.lastname: Tran
authors.affiliation: b School of Life Sciences, Heriot Watt University , Edinburgh , UK , and.
authors.forename: Helinor
authors.initials: H
authors.lastname: Johnston
authors.affiliation: a Moredun Research Institute, Pentlands Science Park , Penicuik , UK .
authors.forename: Joyce
authors.initials: J
authors.lastname: McLuckie
authors.affiliation: a Moredun Research Institute, Pentlands Science Park , Penicuik , UK .
authors.forename: Karen
authors.initials: K
authors.lastname: Stevenson
authors.affiliation: b School of Life Sciences, Heriot Watt University , Edinburgh , UK , and.
authors.forename: Vicki
authors.initials: V
authors.lastname: Stone
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D050296:Microbial Viability / Q000187:drug effects; D009162:Mycobacterium avium / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D000900:Anti-Bacterial Agents; D049452:Green Fluorescent Proteins
keywords: Antibacterial activity; antibiotic resistance; drug screening; mycobacterium; nanomedicine