Our Work: Listeria monocytogenes
The Guariglia lab employs an array of genomic approaches (e.g. WGS, RNA-seq, Tn-seq) as well as traditional microbiology and molecular genetic techniques, to study L. monocytogenes pathogenesis, transmission and control.
Our lab uses the foodborne pathogen Listeria monocytogenes as a model pathogenic microorganism. L. monocytogenesis a facultative, intracellular, human and animal pathogen that causes invasive listeriosis, one of the leading causes of death from foodborne illness in the U.S and Canada. In addition, food recalls due to contamination of foods by L. monocytogenes is a major economic burden for the global economy.
L. monocytogenes is a particularly problematic pathogen as it can survive and thrive under many different environments, such as the soil, produce, hard to reach niches in processing plants, processed Ready-to-Eat foods, the GI tract, and the intracellular environment. Understanding how Listeria is able to survive and adapt to its changing environments is crucial for the improvement of current and development of new strategies for the control of its spread and transmission.
Current Projects
Understanding cell envelope modification pathways to facilitate development of improved control strategies for bacterial foodborne pathogens
Mechanistic understanding of the interplay between Sigma B and PrfA and the gene expression battle influencing Listeria monocytogenes virulence.
Recent Publications:
Chen R, Skeens JW, Wiedmann M, Guariglia-Oropeza V. The efficacy of nisin against Listeria monocytogenes on cold-smoked salmon at natural contamination levels is concentration-dependent and varies by serotype. Front Microbiol. 2022 Sep 6;13:930400. doi: 10.3389/fmicb.2022.930400. PMID: 36147859; PMCID: PMC9486479.
Chen R, Orsi RH, Guariglia-Oropeza V, Wiedmann M. Development of a Modeling Tool To Assess and Reduce Regulatory and Recall Risks for Cold-Smoked Salmon Due to Listeria monocytogenes Contamination. J Food Prot. 2022 Sep 1;85(9):1335-1354. doi: 10.4315/JFP-22-025. PMID: 35723598.
Gaballa A, Sunil S, Doll E, Murphy SI, Bechtel T, Guariglia-Oropeza V, Wiedmann M. Characterization of the roles of activated charcoal and Chelex in the induction of PrfA regulon expression in complex medium. PLoS One. 2021 Apr 29;16(4):e0250989. doi: 10.1371/journal.pone.0250989. PMID: 33914817; PMCID: PMC8084165.
Harrand AS, Guariglia-Oropeza V, Skeens J, Kent D, Wiedmann M. Nature versus Nurture: Assessing the Impact of Strain Diversity and Pregrowth Conditions on Salmonella enterica, Escherichia coli, and Listeria Species Growth and Survival on Selected Produce Items. Appl Environ Microbiol. 2021 Feb 26;87(6):e01925-20. doi: 10.1128/AEM.01925-20. PMID: 33397695; PMCID: PMC8105001.