Elucidation of Proteus mirabilis as a Key Bacterium in Crohn's Disease Inflammation.

Background & Aims: Proteus spp, Gram-negative facultative anaerobic bacilli, have recently been associated with Crohn's disease (CD) recurrence after intestinal resection. We investigated the genomic and functional role of Proteus as a gut pathogen in CD.

Methods: Proteus spp abundance was assessed by ure gene-specific polymerase chain in 54 pairs of fecal samples and 101 intestinal biopsies from patients with CD and healthy controls.

Untargeted accurate identification of highly pathogenic bacteria directly from blood culture flasks.

To improve the preparedness against exposure to highly pathogenic bacteria and to anticipate the wide variety of bacteria that can cause bloodstream infections (BSIs), a safe, unbiased and highly accurate identification method was developed. Our liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based method can identify highly pathogenic bacteria, their near-neighbors and bacteria that are common causes of BSIs directly from positive blood culture flasks. The developed Peptide-Based Microbe Detection Engine (http://proteome2pathogen.

Identification of microorganisms grown in blood culture flasks using liquid chromatography-tandem mass spectrometry.

Aim: Bloodstream infections are a common cause of disease and a fast and accurate identification of the causative agent or agents of bloodstream infections would aid the start of adequate treatment.

Materials & Methods: A liquid chromatography-tandem mass spectrometry (LC-MS/MS) shotgun proteomics method was developed for the identification of bacterial species directly from blood cultures that were simulated by inoculating blood culture bottles with single or multiple clinically relevant microorganisms.

Results: Using LC-MS/MS, the single species were correctly identified in 100% of the blood cultures, whereas for polymicrobial infections, 78% of both species were correctly identified in blood cultures.

Two complementary approaches to quantify variability in heat resistance of spores of Bacillus subtilis.

Realistic prediction of microbial inactivation in food requires quantitative information on variability introduced by the microorganisms. Bacillus subtilis forms heat resistant spores and in this study the impact of strain variability on spore heat resistance was quantified using 20 strains. In addition, experimental variability was quantified by using technical replicates per heat treatment experiment, and reproduction variability was quantified by using two biologically independent spore crops for each strain that were heat treated on different days.

High-Level Heat Resistance of Spores of and Results from the Presence of a Operon in a Tn Transposon.

Bacterial endospore formers can produce spores that are resistant to many food processing conditions, including heat. Some spores may survive heating processes aimed at production of commercially sterile foods. Recently, it was shown that a operon, designated , present on a Tn transposon in , leads to profoundly increased wet heat resistance of spores.

A mobile genetic element profoundly increases heat resistance of bacterial spores.

Bacterial endospores are among the most resilient forms of life on earth and are intrinsically resistant to extreme environments and antimicrobial treatments. Their resilience is explained by unique cellular structures formed by a complex developmental process often initiated in response to nutrient deprivation. Although the macromolecular structures of spores from different bacterial species are similar, their resistance to environmental insults differs widely.

A transposon present in specific strains of Bacillus subtilis negatively affects nutrient- and dodecylamine-induced spore germination.

Spore germination shows a large inter-strain variability. Spores of certain Bacillus subtilis strains, including isolates from spoiled food products, exhibit different germination behavior from spores of the well-studied model organism Bacillus subtilis 168, often for unknown reasons. In this study, we analyzed spore germination efficiencies and kinetics of seventeen B.

Genome Sequences of 12 Spore-Forming Bacillus Species, Comprising Bacillus coagulans, Bacillus licheniformis, Bacillus amyloliquefaciens, Bacillus sporothermodurans, and Bacillus vallismortis, Isolated from Foods.

Here, we report the draft genomes of twelve isolates of five different Bacillus species, all spore-forming, Gram-positive bacteria.

Draft Genome Sequences of Seven Thermophilic Spore-Forming Bacteria Isolated from Foods That Produce Highly Heat-Resistant Spores, Comprising Geobacillus spp., Caldibacillus debilis, and Anoxybacillus flavithermus.

Here, we report the draft genomes of five strains of Geobacillus spp., one Caldibacillus debilis strain, and one draft genome of Anoxybacillus flavithermus, all thermophilic spore-forming Gram-positive bacteria.

Draft Genome Sequences of 10 Bacillus subtilis Strains That Form Spores with High or Low Heat Resistance.

Here, we report the draft genome sequences of 10 isolates of Bacillus subtilis, a spore forming Gram-positive bacterium. The strains were selected from food products and produced spores with either high or low heat resistance.

Bacterial Spores in Food: Survival, Emergence, and Outgrowth.

Spore-forming bacteria are ubiquitous in nature. The resistance properties of bacterial spores lie at the heart of their widespread occurrence in food ingredients and foods. The efficacy of inactivation by food-processing conditions is largely determined by the characteristics of the different types of spores, whereas food composition and storage conditions determine the eventual germination and outgrowth of surviving spores.

Next-Generation Whole-Genome Sequencing of Eight Strains of Bacillus cereus, Isolated from Food.

Bacillus cereus can contaminate food and cause emetic and diarrheal foodborne illness. Here, we report whole-genome sequences of eight strains of B. cereus, isolated from different food sources.

Bacillus thermoamylovorans Spores with Very-High-Level Heat Resistance Germinate Poorly in Rich Medium despite the Presence of ger Clusters but Efficiently upon Exposure to Calcium-Dipicolinic Acid.

High-level heat resistance of spores of Bacillus thermoamylovorans poses challenges to the food industry, as industrial sterilization processes may not inactivate such spores, resulting in food spoilage upon germination and outgrowth. In this study, the germination and heat resistance properties of spores of four food-spoiling isolates were determined. Flow cytometry counts of spores were much higher than their counts on rich medium (maximum, 5%).

Draft Genome Sequences of Four Bacillus thermoamylovorans Strains Isolated from Milk and Acacia Gum, a Food Ingredient.

The thermophilic bacterium Bacillus thermoamylovorans produces highly heat-resistant spores that can contaminate food products, leading to their spoilage. Here, we present the whole-genome sequences of four B. thermoamylovorans strains, isolated from milk and acacia gum.

Draft Genome Sequences of Five Spore-Forming Food Isolates of Bacillus pumilus.

Here, we report the draft genome sequences of five food isolates of Bacillus pumilus, a spore-forming Gram-positive bacterium.

Two distinct groups within the Bacillus subtilis group display significantly different spore heat resistance properties.

The survival of bacterial spores after heat treatment and the subsequent germination and outgrowth in a food product can lead to spoilage of the food product and economical losses. Prediction of time-temperature conditions that lead to sufficient inactivation requires access to detailed spore thermal inactivation kinetics of relevant model strains. In this study, the thermal inactivation kinetics of spores of fourteen strains belonging to the Bacillus subtilis group were determined in detail, using both batch heating in capillary tubes and continuous flow heating in a micro heater.

Effects of altered TatC proteins on protein secretion efficiency via the twin-arginine translocation pathway of Bacillus subtilis.

Protein translocation via the Tat machinery in thylakoids and bacteria occurs through a cooperation between the TatA, TatB and TatC subunits, of which the TatC protein forms the initial Tat substrate-binding site. The Bacillus subtilis Tat machinery lacks TatB and comprises two separate TatAC complexes with distinct substrate specificities: PhoD is secreted by the TatAdCd complex, whereas YwbN is secreted by the TatAyCy complex. To study the role of the Gram-positive TatC proteins in Tat-dependent protein secretion efficiency, we applied several genetic engineering approaches to modify and analyse the B.