Title of Document: INHIBITORS OF AUTOINDUCER-2 QUORUM SENSING AND THEIR EFFECT ON BACTERIAL BIOFILM FORMATION Rebecca Melissa Lennen, Master of Science, 2007 Directed by: Dr. William Bentley, Professor Department of Bioengineering Bacteria utilize small signaling molecules, or autoinducers, to regulate their gene expression in tandem by a process termed quorum sensing. The gene encoding the syn...

The bacteriolytic activity of CTL is mediated by granulysin, which has been reported to kill intracellular Mycobacterium tuberculosis in dendritic cells (DC) with high efficiency. Despite that crucial effector function, the killing mechanism and uptake of granulysin into target cells have not been well investigated. To this end we analyzed granulysin binding, uptake, and the subsequent lysis of...

Four Enterococcus faecium strains isolated from fermented products were evaluated for potential use as probiotic strains. In addition to efaAfm gene, commonly found in E. faecium food isolates, none of the isolates possessed virulence genes and none had positive reactions for the production of tyramine, histamine, putrescine and cadaverine in the screening medium used. All of these four isolate...

AIM The present study was undertaken with the prime objective of isolating and identifying Listeria spp. from various foods of animal origin sold at retail market outlets in the city of Navsari, Gujarat. MATERIALS AND METHODS Total 200 samples comprising of milk, milk products, meat, and fish (50 each) collected aseptically from local market which were subjected first to pre-enrichment in hal...

Identification of 12 strains originally characterized as nonpathogenic Listeria monocytogenes was reassured following the evaluation of their hemolytic capability with a newly developed horse blood agar plate. Seven of the strains were observed consistently to be hemolytic and confirmed as L. monocytogenes with the use of two commercial systems: the Gene-Trak L. monocytogenes-specific colorimet...

At 56 weeks of age, 30 Hyline (W-377) laying pullets were randomly distributed in individual (1 pullet per cage) 45 x 45 x 35 cm cages. Cracked egg was used as protein supplement to the diet. Three groups of 10 Hyline laying pullets each were formed. Three isocaloric and isonitrogenous diets were prepared from different protein sources as followed: ration 1 (control) − soybean meal; ration 2 (e...

Listeria monocytogenes, a psychrotrophic foodborne pathogen, is a recurring postprocess contaminant on ready-to-eat meat (RTE) products, including frankfurters. Potassium lactate (PL) and sodium diacetate (SDA) are FDA-approved antimicrobials that inhibit the growth of L. monocytogenes when incorporated into the formulation of fine emulsion sausage. Flash (steam) pasteurization (FP) has been sh...

Listeria spp. isolated from different food products and collected from 12 Brazilian states were sent to the Laboratory of Bacterial Zoonoses (Oswaldo Cruz Institute, Brazil) for identification. The aims of this study were to characterize these isolates, from 1990 to 2012, by using biochemical, morphological, and serotyping tests, and to analyze the distribution of L. monocytogenes serotypes on ...