Matthew R. Parsek
My research involves the study of bacterial communities. This research focuses on two aspects that are closely related. Quorum sensing is a term used to describe the regulation of gene expression according to population densities, many Gram-negative bacteria use specific signaling molecules, called acyl-homoserine lactones (acy-HSLs), to sense the presence of other bacteria of the same species in the bacterial cell membrane. At high cell densities the acyl-HSL reaches a critical concentration at which expression of quorum sensing-controlled genes is induced. Therefore, quorum sensing constitutes a rudimentary communication system between bacteria that allows them to coordinate behavior at the community level.
We are also interested in the surface-attached bacterial communities called biofilms. These bacteria are held together by an extracellular matrix. Most bacteria in the environment exist as biofilms and biofilm bacteria have been shown to possess unique characteristics that are not seen in conventional test tube-grown bacteria. It has also been estimated recently that up to 67% of bacterial infections involve biofilm bacteria. Therefore there is a growing appreciation for the need to study biofilm bacteria.
We use the opportunistic pathogen, Pseudomonas aeruginosa, as a model organism for our research. P. aeruginosa is responsible for a variety of nosocomial infections. It is also the primary infectious agent in lung infections of people suffering from Cystic Fibrosis. Recently, we determined that quorum sensing is important for normal biofilm development. This finding has important implications for understanding and controlling both clinical and environmental biofilms. We are trying to understand the mechanism of quorum sensing in biofilms at the molecular level. We also are interested in the extracellular matrix of P. aeruginosa biofilms - what is it made of? and how does it contribute to antimicrobial resistance? Our research utilizes cutting-edge technology such as scanning confocal laser microscopy and techiques from the fields of molecular biology, biochemistry, and bacterial pathogenesis.
Recent Publications from PubMed
- Reichhardt C, Parsek MRFrontiers in microbiology. 2019 ; 10 : 677
- Treatment with the glycoside hydrolase PslG combats wound infection by improving antibiotic efficacy and host innate immune activity.Pestrak MJ, Baker P, Dellos-Nolan S, Hill PJ, da Silva DP, Silver H, Lacdao I, Raju D, Parsek MR, Wozniak DJ, Howell PLAntimicrobial agents and chemotherapy. 2019 Apr; :
- CdrA Interactions within the Pseudomonas aeruginosa Biofilm Matrix Safeguard It from Proteolysis and Promote Cellular Packing.Reichhardt C, Wong C, Passos da Silva D, Wozniak DJ, Parsek MRmBio. 2018 09; 9 5:
- Pseudomonas aeruginosa utilizes host polyunsaturated phosphatidylethanolamines to trigger theft-ferroptosis in bronchial epithelium.Dar HH, Tyurina YY, Mikulska-Ruminska K, Shrivastava I, Ting HC, Tyurin VA, Krieger J, St Croix CM, Watkins S, Bayir E, Mao G, Armbruster CR, Kapralov A, Wang H, Parsek MR, Anthonymuthu TS, Ogunsola AF, Flitter BA, Freedman CJ, Gaston JR, Holman TR, Pilewski JM, Greenberger JS, Mallampalli RK, Doi Y, Lee JS, Bahar I, Bomberger JM, Bayır H, Kagan VEThe Journal of clinical investigation. 2018 Oct; 128 10: 4639-4653
- A Biofilm Matrix-Associated Protease Inhibitor Protects Pseudomonas aeruginosa from Proteolytic Attack.Tseng BS, Reichhardt C, Merrihew GE, Araujo-Hernandez SA, Harrison JJ, MacCoss MJ, Parsek MRmBio. 2018 04; 9 2: