To measure sigmaB activation in Listeria monocytogenes under environmental or energy stress conditions, quantitative reverse transcriptase PCR (TaqMan) was used to determine the levels of transcripts for the sigmaB -dependent opuCA and clpC genes in strains having null mutations in genes encoding regulator of sigma B proteins (rsbT and rsbV) and sigma B (sigB) and in the L. monocytogenes wild-t...

Escherichia coli sfa+ strains isolated from poultry were serotyped and characterized by polymerase chain reaction (PCR) and amplified fragment length polymorphism (AFLP). Isolates collected from 12 Brazilian poultry farms mostly belonged to serogroup O6, followed by serogroups O2, O8, O21, O46, O78, O88, O106, O111, and O143. Virulence genes associated were: iuc 90%, fim 86% neuS 60%, hly 34%, ...

Accepted: 11/07/2014 Abstract The study was carried out to standardize a multiplex PCR assay for the simultaneous detection of four common food pathogens such as Listeria monocytogenes, Yersinia enterocolitica, Staphylococcus aureus and Salmonella enterica Typhimurium. Pathogen-specific DNA primers targeting hly A, ail, nuc and stm genes were employed for the identification of L. monocytogenes,...

The population of Listeria monocytogenes and the expression five virulence stress-related genes in pressurized dry-cured ham were monitored throughout storage at 4 °C. L. strains S2 (serotype 1/2a) S7-2 4b) exhibited a moderate resistance to high pressure processing (HPP) 450 MPa for 10 min or 600 5 min. low water activity (aw) sliced (aw = 0.88) diminished efficacy treatments, with pathogen re...

Vibrio cholerae is an aerobic, sucrose fermentative Gram-negative bacterium that generally prevails in the environment. Pathogenic V. cholerae is well-known as causative agent of acute diarrhea. Apart from enteric infections, V. cholerae may also cause other diseases. However, their role in causing extraintestinal infections is not fully known as it needs proper identification and evaluation. F...

Q1'TE independently of each other, the Q authors of this brief report developed a simple technic which, without the use of special equipment, allows the percutanleous insertion of large bore polyethylene tubing into 1)loo0( vessels. Certain features have beci used by others.' 'It is self-evident that the rigid poinit of a hly)oderlmic needle, though desirable for percutaneous insertion into blo...

Bordetellae, pathogenic to mammals, produce an immunomodulatory adenylate cyclase toxin-hemolysin (CyaA, ACT or AC-Hly) that enables them to overcome the innate immune defense of the host. CyaA subverts host phagocytic cells by an orchestrated action of its functional domains, where an extremely catalytically active adenylyl cyclase enzyme is delivered into phagocyte cytosol by a pore-forming r...

Supercoiled minicircular deoxyribonucleic acid (DNA) molecules with molecular weights of 1.8 x 10(6) and 2.3 x 10(6) have been isolated from two wild strains of Escherichia coli. DNA-DNA hybridization experiments indicate that these DNA molecules share extended homologies with the minicircular DNA of E. coli 15. The DNA of the colicinogenic factor E1 (ColE1) also hybridizes to a large extent wi...

The effect of rIFN-gamma and rTNF on the fate of hemolytic and nonhemolytic (hly-) Listeria monocytogenes in cultured mouse peritoneal macrophages was investigated. In untreated macrophages, approximately 80% of the hemolytic bacteria were killed during the first 2 h of incubation, but the survivors doubled between two and three times. In rIFN-gamma-treated macrophages, although the bacterial k...

term stress is used, most often subjectively, with various meanings, the physiological inition, and appropriate term as responses in different situations. The flexibility of normal tabolism allows the development of responses to environmental changes which fluctuate ularly and predictable over daily and seasonal cycles. Thus every deviation of a factor its optimum does not necessarily result in...