Phage Cd2 and Lactic Acid Bacteria, New Strategies in Food Safety and Quality Preservation

Abstract

Lactic Acid Bacteria (LAB) play a key role in the food industry. They are essential for the production of fermented foods and they can also inhibit the growth of pathogenic bacteria, such as Listeria, since they naturally produce an array of antimicrobial peptides. However, certain species of LAB, such as Carnobacteria, are also associated with food spoilage. As such, the selective control of LAB is an important quest in the food industry. Recently, we is0lated bacteriophage cd2, a phage that selectively kills Carnobacterium divergens. To better understand the potential use of this phage for the biocontrol of C. divergens, we have examined its biochemical and genetic features. Our results indicate that phage cd2 is a virulent phage with an infection cycle of 70 minutes, is fully active across a broad pH range (4-12) and is heat-sensitive (fully inactivated by treated at 60^oC). Genome sequencing and analysis shows that the 55 kb genome shares limited homology with several enterococcal phages, and likely encodes ~90 genes. Future work is focused on identifying and studying the mechanisms by which phage cd2 selectively recognizes and kills C. divergens.

*Indicates faculty mentor