Biofilm Formation by Listeria monocytogenes

Summary

Principal Investigator: KATHERINE PAIGE LEMON
Abstract: [unreadable] DESCRIPTION (provided by applicant): Project Summary: This application details a five year research career development program designed to explore biofilm formation by the food-borne pathogen Listeria monocytogenes under the guidance of Dr. Roberto Kolter, Professor in the Department of Microbiology and Molecular Genetics at Harvard Medical School. Dr. Kolter is a leader in the field of microbial biofilm development and has an excellent track record of mentoring his trainees to positions as independent investigators. My long-term goal is to become an independent clinician-researcher. To this end, I have trained in both pediatric infectious diseases and biology. This proposal is designed to prepare me to be an independent researcher studying biofilm formation by L. monocytogenes. This field of study is very different from my prior research and my plan includes coursework in bacterial metabolism and bioinformatics. The gram-positive bacterium L. monocytogenes is a food-borne pathogen that causes severe, even fatal, infections in fetuses, newborns, and immunocompromised people. L. monocytogenes persisting on food preparation surfaces in the form of biofilms is a source of contamination that leads to listeriosis outbreaks. Biofilms are highly organized, matrixenclosed assemblages of microbial cells. Of particular relevance to both medicine and the food industry, biofilm bacteria are more resistant to detergents, biocides, and antibiotics than are individual, free-living bacteria. This makes decontamination of biofilm-coated surfaces particularly difficult. Although little is known about how Listeria forms biofilms, Listeria pathogenesis is well studied. As a result, a number of genetic and genomic tools are available. The experiments proposed herein are designed to determine: (1) what L. monocytogenes genes are required for biofilm formation using transposon and targeted mutagenesis, and (2) what are the physiological differences between individual free-living bacteria and biofilm-associated bacteria for L. monocytogenes using DNA microarray technology. Insights gained from these experiments should lead to new approaches to decontaminate biofilm-coated surfaces, and a better understanding of biofilms in general. Relevance: Prevention by eliminating sources of infection remains a cornerstone in the continued effort to decrease the human and economic toll of infectious diseases. Ingestion of food contaminated with Listeria monocytogenes can cause severe, sometimes fatal, infections in newborns, pregnant women and people with compromised immune systems. The research I have proposed will lay the foundation for understanding how Listeria monocytogenes persists in the environment in biofilms on surfaces, such as those in food processing centers, where it can be a source of infection. [unreadable] [unreadable] [unreadable]
Funding Period: 2006-06-01 - 2010-04-30
more information: NIH RePORT

Top Publications

  1. pmc Flagellar motility is critical for Listeria monocytogenes biofilm formation
    Katherine P Lemon
    Division of Infectious Diseases, Children s Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
    J Bacteriol 189:4418-24. 2007
  2. pmc Biofilm development with an emphasis on Bacillus subtilis
    K P Lemon
    Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA
    Curr Top Microbiol Immunol 322:1-16. 2008
  3. pmc The virulence regulator PrfA promotes biofilm formation by Listeria monocytogenes
    Katherine P Lemon
    Division of Infectious Diseases, Children s Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
    J Bacteriol 192:3969-76. 2010
  4. pmc High-throughput assay for bacterial adhesion on acellular dermal matrices and synthetic surgical materials
    Theodore T Nyame
    Division of Plastic and Reconstructive Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
    Plast Reconstr Surg 128:1061-8. 2011

Detail Information

Publications4

  1. pmc Flagellar motility is critical for Listeria monocytogenes biofilm formation
    Katherine P Lemon
    Division of Infectious Diseases, Children s Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
    J Bacteriol 189:4418-24. 2007
    ..Also, any role for L. monocytogenes flagella as adhesins on abiotic surfaces appears to be either minimal or motility dependent under the conditions we examined...
  2. pmc Biofilm development with an emphasis on Bacillus subtilis
    K P Lemon
    Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA
    Curr Top Microbiol Immunol 322:1-16. 2008
    ..While the ability of bacteria to form a biofilm appears to be almost universal and overarching themes apply, the combination of molecular events necessary varies widely, and this is reflected in the other chapters of this book...
  3. pmc The virulence regulator PrfA promotes biofilm formation by Listeria monocytogenes
    Katherine P Lemon
    Division of Infectious Diseases, Children s Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
    J Bacteriol 192:3969-76. 2010
    ..monocytogenes. The requirement of PrfA for optimal biofilm formation may provide selective pressure to maintain this critical virulence regulator when L. monocytogenes is outside host cells in the environment...
  4. pmc High-throughput assay for bacterial adhesion on acellular dermal matrices and synthetic surgical materials
    Theodore T Nyame
    Division of Plastic and Reconstructive Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
    Plast Reconstr Surg 128:1061-8. 2011
    ..The authors have designed a high-throughput assay to evaluate Staphylococcus aureus adherence on various synthetic and biologically derived materials...