The Smu0630 protein (AtlA) was recently shown to be involved in cell separation, biofilm formation, and autolysis. Here, transcriptional studies revealed that atlA is part of a multigene operon under the control of at least three promoters. The morphology and biofilm-forming capacity of a nonpolar altA mutant could be restored to that of the wild-type strain by adding purified AtlA protein to t...

Pulmonary inflammation can contribute to the development of lung cancer in humans. We investigated whether pulmonary inflammation alters the genotoxicity of polycyclic aromatic hydrocarbons (PAHs) in the lungs of mice and what mechanisms are involved. To model nonallergic acute inflammation, mice were exposed intranasally to lipopolysaccharide (LPS; 20 µg/mouse) and then instilled intratracheal...

BACKGROUND Inflammation within the oral cavity occurs due to dysregulation between microbial biofilms and the host response. Understanding how different oral hygiene products influence inflammatory properties is important for the development of new products. Therefore, creation of a robust host-pathogen biofilm platform capable of evaluating novel oral healthcare compounds is an attractive opti...

Mycobacterium avium is widely distributed in the environment, and it is chiefly found in water and soil. M. avium, as well as Mycobacterium smegmatis, has been recognized to produce a biofilm or biofilm-like structure. We screened an M. avium green fluorescent protein (GFP) promoter library in M. smegmatis for genes involved in biofilm formation on polyvinyl chloride (PVC) plates. Clones associ...

A simple and sensitive method was developed to separate the carcinogenic polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (BaP), and six of its oxidation metabolites generated by rat hepatic microsomes enriched with cytochrome P450 (CYP) 1A1, by high pressure liquid chromatography (HPLC). The HPLC method, using an acetonitrile/water gradient as mobile phase and UV detection, provided appro...

The objective of this study was to evaluate the reproductive risk associated with exposure of adult male Fisher-344 rats to inhaled benzo(a)pyrene (BaP), a ubiquitous environmental toxicant present in cigarette smoke, automobile exhaust fumes and industrial emissions. Rats were assigned randomly to a treatment or control group. Treatment consisted of sub-chronic exposure of rats via inhalation ...

The effect of cytochrome P4501A (CYP1A) induction on cell-specific benzo[a]pyrene (BaP) adduct formation was studied in rainbow trout (Oncorhynchus mykiss) gills. Fish preexposed to beta-naphthoflavone (betaNF) or caged in a polluted river were exposed to waterborne 3H-benzo[a]pyrene (3H-BaP). The 3H-benzo[a]pyrene adducts in the gill filaments were localized by autoradiography and CYP1A protei...

This work examined fouling-associated microbial community in a carefully controlled laboratory-scale membrane bioreactor (MBR) at different fouling stages. In agreement with the literature, severity was positively correlated bound polysaccharide and protein content (indicators) mixed liquor. UPGMA clustering analysis indices indicated that although biofouling layer (biofilm) liquor possessed hi...

Pseudomonas aeruginosa is the prototypical biofilm-forming gram-negative opportunistic human pathogen. P. aeruginosa is causatively associated with nosocomial infections and with cystic fibrosis. Antibiotic resistance in some strains adds to the inherent difficulties that result from biofilm formation when treating P. aeruginosa infections. Transcriptional profiling studies suggest widespread c...

[a]pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH) and animal carcinogen, is used by regulators as the basis for quantitative risk estimation of PAH-containing combustion by-products (1). Is BaP an appropriate predictor of cancer risk for products of incomplete combustion? A multidose, 2-year (chronic) feeding protocol developed by the National Institute of Environmental Health Sciences i...