Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING
GLOBETECH PUBLISHING
PZ HTL SA

Immobilized Lytic Enzymes Prevent Listeria Growth on Food-related Surfaces

By BiotechDaily International staff writers
Posted on 18 Apr 2013
A coating of stabilized bacteriophage lytic enzymes could prevent Listeria from surviving on equipment and packaging used in the food industry.

Listeria is a genus of bacteria, of which the most common species is Listeria monocytogenes, commonly found in soil, on unwashed vegetables, and in unpasteurized soft cheeses. These bacteria resist cold and the presence of salt and can cause food poisoning (listeriosis) with flu-like symptoms such as high fever and dizziness. While healthy individuals may not have any symptoms, those with compromised immune systems such as pregnant women, infants, and the elderly are especially at risk.

Investigators at Rensselaer Polytechnic Institute (Troy, NY, USA) previously developed a coating that could kill methicillin-resistant Staphylococcus aureus (MRSA) without antibiotics. In the present study, they observed that while a number of phage cell lytic enzymes against Listeria had been isolated, no attempt had been made to incorporate these enzymes onto surfaces.

The investigators described in the April 2, 2013, online edition of the journal Scientific Reports the development of three simple routes for the surface incorporation of the Listeria bacteriophage endolysin Ply500. These routes included covalent attachment onto [US] Food and Drugs Administration (FDA)-approved silica nanoparticles (SNPs), incorporation of SNP-Ply500 conjugates into a thin poly(hydroxyethyl methacrylate) film, and affinity binding to edible crosslinked starch nanoparticles via construction of a maltose binding protein fusion.

Testing of these coated surfaces revealed that these Ply500 formulations were effective in killing L. innocua (a reduced pathogenic surrogate) at challenges up to 100,000 colony-forming units per milliliter both in non-growth-sustaining buffer solution as well as under growth conditions on lettuce. This is a significantly higher concentration of bacteria than is normally found in contaminated food.

"In this study, we have identified a new strategy for selectively killing specific types of bacteria. Stable enzyme-based coatings or sprays could be used in food supply infrastructure—from picking equipment to packaging to preparation—to kill Listeria before anyone has a chance to get sick from it," said contributing author Dr. Ravi Kane, professor of chemical and biological engineering at Rensselaer Polytechnic Institute. "What is most exciting is that we can adapt this technology for all different kinds of harmful or deadly bacteria."

Related Links:
Rensselaer Polytechnic Institute



Channels

Drug Discovery

view channel
Image: Chitosan is derived from the shells of shrimp and other sea crustaceans, including Alaskan pink shrimp, pictured here (Photo courtesy of NOAA - [US] National Oceanic and Atmospheric Administration).

Chitosan Treatment Clears the Way for Antibiotics to Eliminate Recurrent Urinary Tract Infections

Recurrent urinary tract infection was successfully resolved in a mouse model by treatment with the exfoliant chitosan followed by a round of antibiotics. Bacterial urinary tract infection (UTI), most... Read more

Biochemistry

view channel

Mitochondrial Cause of Aging Can Be Reversed

Researchers have found a cause of aging in lab animals that can be reversed, possibly providing an avenue for new treatments for age-related diseases including type 2 diabetes, cancer, muscle wasting, and inflammatory diseases. The researchers plan to begin human trials late 2014. The study, which was published December... Read more

Therapeutics

view channel

Cytokine Identified That Causes Mucositis in Cancer Therapy Patients

The action of the cytokine interleukin 1-beta (IL-1beta) has been found to underlie the onset of mucositis, a common, severe side effect of chemotherapy and irradiation of cancer patients. Mucositis occurs as a result of cell death in reaction to chemo- or radiotherapy. The mucosal lining of the mouth becomes thin, may... Read more

Business

view channel

Analytical Sciences Trade Fair Declared a Rousing Success

Organizers of this year's 24th "analytica" biosciences trade fair have reported significant increases in both the number of visitors and exhibitors compared to the 2012 event. The analytica trade fair for laboratory technology, analysis, and biotechnology has been held at the Munich (Germany) Trade Fair Center every... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.