Characterization of the codY gene and its influence on biofilm formation in Bacillus cereus.

The foodborne pathogen Bacillus cereus can form biofilms on various food contact surfaces, leading to contamination of food products. To study the mechanisms of biofilm formation by B. cereus, a Tn5401 library was generated from strain UW101C.

Biosurfactant production and surface translocation are regulated by PlcR in Bacillus cereus ATCC 14579 under low-nutrient conditions.

Bacillus cereus ATCC 14579 can respond to nutrient changes by adopting different forms of surface translocation. The B. cereus ATCC 14579 DeltaplcR mutant, but not the wild type, formed dendritic (branched) patterns on EPS [a low-nutrient medium that contains 7.

Biofilm formation by Bacillus cereus is influenced by PlcR, a pleiotropic regulator.

The DeltaplcR mutant of Bacillus cereus strain ATCC 14579 developed significantly more biofilm than the wild type and produced increased amounts of biosurfactant. Biosurfactant production is required for biofilm formation and may be directly or indirectly repressed by PlcR, a pleiotropic regulator. Coating polystyrene plates with surfactin, a biosurfactant from Bacillus subtilis, rescued the deficiency in biofilm formation by the wild type.

Differential biofilm formation and motility associated with lipopolysaccharide/exopolysaccharide-coupled biosynthetic genes in Stenotrophomonas maltophilia.

Stenotrophomonas maltophilia WR-C is capable of forming biofilm on polystyrene and glass. The lipopolysaccharide/exopolysaccharide-coupled biosynthetic genes rmlA, rmlC, and xanB are necessary for biofilm formation and twitching motility. Mutants with mutations in rmlAC and xanB display contrasting biofilm phenotypes on polystyrene and glass and differ in swimming motility.

Efficacy of two cleaning and sanitizing combinations on Listeria monocytogenes biofilms formed at low temperature on a variety of materials in the presence of ready-to-eat meat residue.

Biofilms in the food-processing industry are a serious concern due to the potential for contamination of food products, which may lead to decreased food quality and safety. The effect of two detergent and sanitizer combinations on the inactivation of Listeria monocytogenes biofilms was studied. Combination A uses a chlorinated-alkaline, low-phosphate detergent, and dual peracid sanitizer.

Attachment of Listeria monocytogenes and Salmonella typhimurium to Stainless Steel and Buna-N in the Presence of Milk and Individual Milk Components.

The effects of milk and individual milk components on the attachment of Listeria monocytogenes and Salmonella typhimurium to two commonly used materials in the dairy industry were studied. Attachment of both organisms to stainless steel and Buna-N was significantly inhibited by the presence of skim, 2%, whole, or chocolate 2% milk compared to the phosphate-buffered saline (PBS) control. The addition of individual milk components, casein, α-lactalbumin, and β-lactoglobulin to the attachment menstruum significantly reduced attachment.

Antibotulinal Effectiveness of Nisin in Pasteurized Process Cheese Spreads.

Pasteurized process cheese spreads were prepared at moisture levels ranging from 52 to 57% with added sodium chloride at levels from 0 to 2.0%, with disodium phosphate levels ranging from 1.4 to 2.

Evaluation of the Antibotulinal Effectiveness of Nisin in Bacon.

Nisin in combination with nitrite is an effective antibotulinal treatment for bacon. However, rather high levels of nisin (100 to 150 ppm) are required in combination with 120 ppm nitrite to provide a brief, 1-wk extension of shelf life for inoculated bacon incubated at 27°C. This limited antibotulinal effectiveness of nisin in bacon would have little practical value.

Antibotulinal Effectiveness of Nisin-Nitrite Combinations in Culture Medium and Chicken Frankfurter Emulsions.

Chicken frankfurter emulsions were challenged with ca. 1000 C. bolulinum spores/g and incubated at 27°C.