This study evaluated the effects of frankfurter fat content on Listeria monocytogenes resistance to heat stress and gastric fluid, and the Caco-2 cell invasion efficiency of the pathogen. A 10-strain mixture of L. monocytogenes was inoculated on frankfurters formulated with 10%, 20%, and 30% fat content (10%: F10, 20%: F20, 30%: F30) and stored at 10℃ for 30 d. The samples were analyzed for L. ...

A rapid and reliable analytical method was developed to detect and confirm the presence of Listeria monocytogenes in raw and partially processed foods. Forty-nine food samples (25 mixed cut vegetable salad, 12 smoked salmon, and 12 sterile smoked salmon) were individually inoculated with high levels [10-100 colony forming units (cfu)/25 g sample] and low levels (1-10 cfu/25 g sample) of L. mono...

In this paper, the antibacterial effects of the Bacillus amyloliquefaciens-produced bacteriocin subtilosin, both alone and in combination with curcumin, ε-poly-L-lysine (poly-lysine), or zinc lactate, were examined against Listeria monocytogenes. Results indicated that subtilosin inhibits both of the studied bacterial strains, Scott A (wild-type, nisin sensitive) and NR30 (nisin resistant). How...

There have been no studies on the susceptibility and host immune responses to an intranasal infection with Listeria monocytogenes. In this study, we compared the susceptibilities and cytokine responses between intranasal and intravenous infections with L. monocytogenes in mice. Moreover, we compared efficiency of acquisition of host resistance to L. monocytogenes infection between intranasally ...

The bacterium L. monocytogenes is a proposed vaccine carrier based upon the observation that this pathogen replicates within the intracytoplasmic environment facilitating delivery of Ag to the endogenous Ag processing and presentation pathway with subsequent stimulation of peptide specific MHC class I-restricted CD8(+) effector cells. In this report, we evaluate virulence-attenuated strains of ...

Listeria monocytogenes is a gram-positive, intracellular, food-borne pathogen capable of causing severe infections in immunocompromised or pregnant individuals, as well as numerous animal species. Genetic analysis of Listeria pathogenesis has identified several genes which are crucial for virulence. The transcription of most of these genes has been shown to be induced upon entry of Listeria int...

Two virulence factors of Listeria monocytogenes, listeriolysin O (LLO) and phosphatidylinositol-specific phospholipase C (PI-PLC), mediate escape of this pathogen from the phagocytic vacuole of macrophages, thereby allowing the bacterium access to the host cell cytosol for growth and spread to neighboring cells. We characterized their orthologs from Bacillus anthracis by expressing them in L. m...

Listeria monocytogenes is well known for its robust physiology, which permits growth at low temperatures under conditions of high osmolarity and low pH. Although studies have provided insight into the mechanisms used by L. monocytogenes to allay the physiological consequences of these adverse environments, little is known about how these responses are coordinated. In the studies presented here,...

Listeria monocytogenes is well known for its robust physiology, which permits growth at low temperatures under conditions of high osmolarity and low pH. Although studies have provided insight into the mechanisms used by L. monocytogenes to allay the physiological consequences of these adverse environments, little is known about how these responses are coordinated. In the studies presented here,...