Molecular serogrouping of Shiga toxin-producing Escherichia coli using suspension array.

A suspension array assay was developed for molecular serotyping of the seven most prevalent Shiga toxin-producing Escherichia coli (STEC) serogroups (O26, O45, O103, O111, O121, O145, and O157). Fluorescence values of 59 STEC were 30 to >270 times greater than the signals of negative controls, demonstrating the method's effectiveness for the molecular serotyping of STEC.

Non-O157 Shiga toxin-producing Escherichia coli in retail ground beef and pork in the Washington D.C. area.

The prevalence and characteristics of non-O157 Shiga toxin-producing Escherichia coli (STEC) in retail ground meat from the Washington D.C. area were investigated in this study.

Rapid, sensitive and label-free detection of Shiga-toxin producing Escherichia coli O157 using carbon nanotube biosensors.

An electronic platform to detect very small amounts of genomic DNA from bacteria without the need for PCR amplification and molecular labeling is described. The system uses carbon nanotube field-effect transistor (FET) arrays whose electrical properties are affected by minute electrical charges localized on their active regions. Two pathogenic strains of E.

Natural Antimicrobials ε-Poly-L-lysine and Nisin A for Control of Oral Microflora.

The present study aims to examine the efficacy of the natural antimicrobial ε-poly-L-lysine against Streptococcus mutans and against total aerobic oral microflora, alone and in combination with the natural antimicrobial peptide nisin. In in vitro studies, natural antimicrobials nisin A and ε-poly-L-lysine synergized in their action against S. mutans, leading to the microorganism's full inhibition, while having a less inhibitory effect on total aerobic oral microbiota.

The Acid Tolerance Response Alters Membrane Fluidity and Induces Nisin Resistance in Listeria monocytogenes.

The ability of L. monocytogenes cells to adapt to a variety of stressors contributes to its growth in a wide range of foods. The present study examines the effect of acid and of the acid tolerance response (ATR) on membrane fluidity and on the organism's resistance to acid and to the bacteriocin nisin.

Changes in Listeria monocytogenes membrane fluidity in response to temperature stress.

Listeria monocytogenes is a food-borne pathogen that has been implicated in many outbreaks associated with ready-to-eat products. Listeria adjusts to various stresses by adjusting its membrane fluidity, increasing the uptake of osmoprotectants and cryoprotectants, and activating the sigma(B) stress factor. The present work examines the regulation of membrane fluidity through direct measurement based on fluorescent anisotropy.