April 27, 2017
A growing area of interest in my lab is the study of polymicrobial interactions. When two microbes are together, they behave very differently from when they are grown individually. In a recent study in the Journal of Bacteriology, work by Steve Bernier (a former member of the lab) now working with Mike Surrette at McMaster University, showed that rhamnolipid surfactants from Pseudomonas aeruginosa could impact the colony morphotype and motility of Burkholderia cepacia complex (Bcc), another resident of the lung of Cystic Fibrosis patients. The figure below show changes in the colonie morphology of one of these Burkolderia strains with increasing concentrations of spect supernatant from P. aeruginosa cultures. This work also identified mutants of Bcc required to respond to rhamnolipids - interestingly, one of these factors was the type IVb-Tad pili.
April 17, 2017
Check out the latest paper from the lab. In this minireview, Amy Baker, a recently graduated PhD student reviews the impact of "stator dynamics" in the regulation of bacterial motility via control of the flagellar machine (left). We think the ability to use different stator sets, regulated in part by c-di-GMP in Pseudomonas aeruginosa, is another mechanism microbes use to control flagellar motility.
April 05, 2017
This past Monday I had the opportunity to speak at the 2017 CF Research Day at McGill University. It was a terrific event, and I enjoyed the opportunity to visit Montreal for the first time in many years. I spoke about some of our recent work studying polymicrobial infections in CF, including published studies from
Laura Filkins,
Nicki Limoli and unpublished work from Giulia Orzai.
April 03, 2017
Giulia Orazi, a PhD stduent in the lab, recently participated in Science Day here at Dartmouth. She worked with a group of middle schoolers showing them an "ice nucleation assay", where bacteria can help form ice! Check out the
coverage in the local paper, the Valley News. Many members of the lab participate in outreach programs with students of all ages.
April 02, 2017
A project launched in Joanna
Goldberg's lab at Emory, and lead by Nicki Limoli, now a postdoc in my lab, investigated how P. aeruginosa and Staphylococcus aureus might be able to coexist in the CF airway, given that
we and others have shown that P. aeruginosa has the ability to kill Staphylococcus aureus when these microbes are grown in co-culture. Building on her previous clinical study, Nicki was able to
show that mucoid P. aeruginosa, the form of this microbe found in chronically infected CF patients, down-regulates the production of HQNO, siderophores and rhamnolipids - all of which can contribute to killing of Staphylococcus aureus (see figure). Thus, the conversion to mucoidy may allow the coexistence of other pathogens in the CF airway. We also thank Lynne Howell and her group at the University of Toronto and Lory Rahme and her group at MGH for their help with these studies.
Check out the latest paper from the lab. In this minireview, Amy Baker, a recently graduated PhD student reviews the impact of "stator dynamics" in the regulation of bacterial motility via control of the flagellar machine (left). We think the ability to use different stator sets, regulated in part by c-di-GMP in Pseudomonas aeruginosa, is another mechanism microbes use to control flagellar motility.
