Oak Ridge Associated Universities
Research on Foodborne Bacteria Pathogens
Mechanisms of Survival and Growth of Listeria Monocytogenes at 4oC and
Their Relationship with Other Environmental Stresses and Virulence
Project # FDA CFSAN 2007-09
A project is available in the Research Participation Program at the Center for Food Safety and Applied Nutrition (CFSAN), U.S. Food and Drug Administration (FDA). The appointee will be assigned to the Office of Applied Research and Safety Assessment, Division of Virulence Assessment in Laurel, Maryland.
Description of Project:
Foodborne listeriosis continues to be one of the major foodborne diseases causing enormous burden to society. Human listeriosis is associated with gastroenteritis, septicemia, meningitis, abortions and death. In the United States the incidence of human listeriosis is reported to be 3 per million population while the rates are much higher among pregnant woman, immuno-compromised and elderly people. The fatality rate is between 15-20%. L.monocytogenes has been isolated from a variety of foods including dairy, meat products, seafood, eggs and vegetables. A careful examination of the major listeriosis outbreaks and sporadic cases indicate that the vast majority of listeriosis cases are foodborne particularly with ready to eat foods with long shelf life and ability to support the growth of L.monocytogenes. Although food preservation at refrigerator temperatures worked well with many foodborne pathogenic bacteria, Listeria poses unique challenge because it can grow reasonably well at refrigeration temperature. At about 4?C L.monocytogenes grows with a doubling time of 1.3 – 1.5 days. The organism can also withstand repeated freezing and thawing and long term storage at sub-zero temperature. L.monocytogenes also reported to exhibit high tolerance to salt and pH making it one of the most tolerant organisms to environmental stress conditions. The goal for this project is to apply current molecular biology, genomics and bioinformatics tools to identify the genes involved in growth of Listeria at refrigerator temperature and understand the biochemical mechanism underlying this phenomenon. Additional goals will include the study of the interaction of cold tolerance and other stress tolerance and virulence potential. Finally, FDA hopes that a clearer understanding of the cold tolerance will help to identify means that would drastically if not completely eliminate Listerial ability to grow at refrigeration temperature. Development of such treatment/s would help to reduce the growth potential Listeria in foods stored for long time at refrigeration temperature thereby reducing the incidence of foodborne listeriosis.
A doctoral degree received within the past five years is required as is US citizenship or lawful permanent resident status. The applicant should have an understanding of the basic principles of microbiology and molecular biology as it applies to study of foodborne bacteria pathogen. The project involves use of current molecular biology methods; the applicant should have demonstrated experience with molecular biology techniques such as gene cloning, sequencing, mutagenesis, PCR, DNA array technology, bioinformatics and working with RNA. A good understanding of the biology and physiology of Listeria monocytogenes will be a plus but not essential.
The appointment is for up to one year and may be renewed for another year upon recommendation of CFSAN and subject to availability of funds. The participant will receive an annual stipend of up to $60,000 depending on background and experience. The participant must show proof of health and medical insurance. Limited inbound travel/moving expenses will be reimbursed. Funds are also available for travel to scientific meetings. The appointment is full time at CFSAN in Laurel, Maryland. Participants do not become employees of CFSAN, FDA, or the program administrator and there are no fringe benefits paid.
The Research Participation Program at CFSAN is administered by the Oak Ridge Institute for Science and Education (ORISE). To be considered for this project, send a current résumé via e-mail to Melissa.Goodman@orau.org or via fax to (865) 241-5219. Please reference Project # 2007-09 on all correspondence and on the subject line of your e-mail. For additional information, contact Ms. Goodman at (865) 241-1294.
Oak Ridge Associated Universities
P.O. Box 117, MS-36
Oak Ridge, TN 37831
Phone: (865) 576-1089
Fax: (865) 241-5219
Employer's Web Site: http://www.orau.org