title: The effects of indoor and outdoor dust exposure on the growth, sensitivity to oxidative-stress, and biofilm production of three opportunistic bacterial pathogens.
abstract: Within the last decade, many studies have highlighted the radical changes in the components of indoor and outdoor dust. For example, agents like automobile emitted platinum group elements and different kinds of organic phthalates and esters have been reported to be accumulating in the biosphere. Humans consistently face dermal, respiratory, and dietary exposures to these particles while indoors and outdoors. In fact, dust particulate matter has been associated with close to 500,000 deaths per year in Europe and about 200,000 deaths per year in the United States. To date, there has been limited examination of the physiological impact of indoor and outdoor dust exposure on normal flora microbes. In this study, the effect of indoor- and outdoor-dust exposure on three opportunistic bacterial species (Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa) was assessed. Specifically, bacterial growth, oxidative stress resistance, and biofilm production were measured following indoor- and outdoor-dust exposures. Studies were conducted in nutritionally-rich and -poor environments typically encountered by bacteria. Surprisingly, indoor-dust (200μg/mL), enhanced the growth of all three bacterial species in nutrient-poor conditions, but slowed growth in nutrient-rich conditions. In nutrient-rich medium, 100μg/mL exposure of either indoor- or outdoor-dust resulted in significantly reduced oxidative stress resistance in E. coli. Most interestingly, dust (indoor and outdoor), either in nutrient-rich or -poor conditions, significantly increased biofilm production in all three bacterial species. These data suggest that indoor and outdoor dust, can modify opportunistic bacteria through altering growth, sensitivity to oxidative stress, and their virulence potential through enhanced biofilm formation.
authors.affiliation: Department of Biology, Texas Southern University, 3100, Cleburne St, Houston, TX 77099, United States.
authors.forename: Mohammed O
authors.initials: MO
authors.lastname: Suraju
authors.affiliation: DeBakey High School for Health Professions, 3100 Shenandoah St, Houston, TX 77021, United States.
authors.forename: Sloan
authors.initials: S
authors.lastname: Lalinde-Barnes
authors.affiliation: DeBakey High School for Health Professions, 3100 Shenandoah St, Houston, TX 77021, United States.
authors.forename: Sachindra
authors.initials: S
authors.lastname: Sanamvenkata
authors.affiliation: Department of Environmental and Interdisciplinary Sciences, Texas Southern University, Houston, TX 77099, United States.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Esmaeili
authors.affiliation: Department of Biology, Texas Southern University, 3100, Cleburne St, Houston, TX 77099, United States.
authors.forename: Shishir
authors.initials: S
authors.lastname: Shishodia
authors.affiliation: Department of Biology, Texas Southern University, 3100, Cleburne St, Houston, TX 77099, United States; Department of Environmental and Interdisciplinary Sciences, Texas Southern University, Houston, TX 77099, United States. Electronic address: rosenzweigja@tsu.edu.
authors.forename: Jason A
authors.initials: JA
authors.lastname: Rosenzweig
mesh_terms: D000391:Air Microbiology; D000393:Air Pollutants / Q000032:analysis* / Q000633:toxicity; D016902:Air Pollution, Indoor / Q000032:analysis; D018441:Biofilms / Q000254:growth & development; D004781:Environmental Exposure / Q000032:analysis* / Q000706:statistics & numerical data; D018384:Oxidative Stress; D052638:Particulate Matter / Q000032:analysis / Q000633:toxicity
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter
keywords: Bacterial pathogenesis; House dust; Platinum group elements; Road dust