Cigarette smoke boosts virulence in Staphylococcus aureus

Exposure to cigarette smoke has long been associated with increased frequency of respiratory infections—which are harder to treat in smoke-exposed people than in those who lack such exposures. Now Ritwij Kulkarni of Columbia University, New York, NY, and colleagues show that cigarette smoke actually boosts virulence of Staphylococcus aureus bacteria. Their study appears in the November 2012 issue of the journal Infection and Immunity.

S. aureus is a normally harmless inhabitant of the , but one which can morph into a dangerous pathogen capable of causing severe, and even fatal infections, says Kulkarni. The new research shows that cigarette smoke can aid and abet that transformation.

Cigarette smoke does so by enhancing S. aureus' ability to form biofilms, which are an important virulence factor, according to the study. The research showed further that reactive oxygen species, such as H2O2, which are concentrated in cigarette smoke, drive biofilm formation, says Kulkarni.

Kulkarni notes that a recent paper, from another group, showed that suppress the gene regulator, "Accessory Gene Regulator," or agr for short. "That fits nicely with our story," he says. "We think control of biofilm formation [and of numerous other in S. aureus] proceeds via agr."

More information: R. Kulkarni, S. Antala, A. Wang, F.E. Amaral, R. Rampersaud, S.J. LaRussa, P.J. Planet, and A.J. Ratner, 2012. Cigarette smoke increases Staphylococcus aureus biofilm formation via oxidative stress. Infect. Immun. 80:3804-3811.

add to favorites email to friend print save as pdf

Related Stories

Evolution of virulence regulation in Staphylococcus aureus

Oct 09, 2008

Scientists have gained insight into the complex mechanisms that control bacterial pathogenesis and, as a result, have developed new theories about how independent mechanisms may have become intertwined during evolution. The ...

Cigarette smoke could alter shape of heart

Nov 13, 2008

Prolonged exposure to cigarette smoke can increase levels of the stress hormone norepinephrine and enzymes in the heart that have the potential to reshape the left ventricle, according to new research at the University of ...

Recommended for you

UN says Syria vaccine deaths was an NGO 'mistake'

41 minutes ago

The recent deaths of Syrian children after receiving measles vaccinations was the result of a "mistake" by a non-governmental partner who mixed in a muscle relaxant meant for anesthesia, a spokesman for the U.N. secretary-general ...

First US child dies from enterovirus D68

1 hour ago

A child in the northeastern US state of Rhode Island has become the first to die from an ongoing outbreak of a respiratory virus, enterovirus D68, health officials said Wednesday.

US Ebola patient had contact with kids: governor

1 hour ago

A man who was diagnosed with Ebola in virus in Texas came in contact with young children, and experts are monitoring them for any signs of disease, governor Rick Perry said Wednesday.

UN worker dies of suspected Ebola in Liberia

1 hour ago

The United Nations mission in Liberia announced on Wednesday the first suspected victim among its employees of the deadly Ebola epidemic ravaging the impoverished west African nation.

AAO-HNSF clinical practice guideline: Tinnitus

1 hour ago

The American Academy of Otolaryngology—Head and Neck Surgery Foundation has released the first ever mutli-disciplinary, evidence-based clinical practice guideline to improve the diagnosis and management of tinnitus, the ...

User comments