Isolation and characterization of Salmonella enterica- and Escherichia coli-specific bacteriophages of the genus Epseptimavirus from wastewater in Minnesota.

Five lytic bacteriophages specific for Salmonella enterica and Escherichia coli were isolated from wastewater in Minnesota. These phages, designated vB_Sal_EH1, vB_Sal_EH2, vB_Sal_EH3, vB_Sal_EH4, and vB_Sal_EH7, were characterized, and their genomes were sequenced. Phylogenetic analysis showed that they grouped within the genus Epseptimavirus, with genome sizes ranging from 108,554 to 115,218 bp.

Improving health system responses when patients are harmed: a protocol for a multistage mixed-methods study.

Introduction: At least 10% of hospital admissions in high-income countries, including Australia, are associated with patient safety incidents, which contribute to patient harm ('adverse events'). When a patient is seriously harmed, an investigation or review is undertaken to reduce the risk of further incidents occurring. Despite 20 years of investigations into adverse events in healthcare, few evaluations provide evidence of their quality and effectiveness in reducing preventable harm.

Cell-free synthesis of the Salmonella specific broad host range bacteriophage, felixO1.

Phage-based biocontrol of foodborne Salmonella is limited by the requisite use of Salmonella to propagate the phages. This limitation can be circumvented by producing Salmonella phages using a cell-free gene expression system (CFE) with a non-pathogenic chassis. Here, we produce the Salmonella phage felixO1 using an E.

PHEIGES: all-cell-free phage synthesis and selection from engineered genomes.

Bacteriophages constitute an invaluable biological reservoir for biotechnology and medicine. The ability to exploit such vast resources is hampered by the lack of methods to rapidly engineer, assemble, package genomes, and select phages. Cell-free transcription-translation (TXTL) offers experimental settings to address such a limitation.

Cell-Free Synthesis and Quantitation of Bacteriophages.

Cell-free transcription-translation (TXTL) enables achieving an ever-growing number of applications, ranging from the rapid characterization of DNA parts to the production of biologics. As TXTL systems gain in versatility and efficacy, larger DNAs can be expressed in vitro extending the scope of cell-free biomanufacturing to new territories. The demonstration that complex entities such as infectious bacteriophages can be synthesized from their genomes in TXTL reactions opens new opportunities, especially for biomedical applications.

Bacteriophage specificity is impacted by interactions between bacteria.

Unlabelled: Predators play a central role in shaping community structure, function, and stability. The degree to which bacteriophage predators (viruses that infect bacteria) evolve to be specialists with a single bacterial prey species versus generalists able to consume multiple types of prey has implications for their effect on microbial communities. The presence and abundance of multiple bacterial prey types can alter selection for phage generalists, but less is known about how interactions between prey shape predator specificity in microbial systems.

A ToxIN homolog from Salmonella enterica serotype Enteritidis impairs bacteriophage infection.

Aims: To determine if the bacteriophage abortive infection system ToxIN is present in foodborne Salmonella and if it protects against infection by bacteriophages specific to enteric bacteria.

Methods And Results: A set of foodborne Salmonella enteritidis isolates from a 2010 eggshell outbreak was identified via BLASTN (basic local alignment search tool nucleotide) queries as harboring a close homolog of ToxIN, carried on a plasmid with putative mobilization proteins. This homolog was cloned into a plasmid vector and transformed into the laboratory strain Salmonella typhimurium LT2 and tested against a set of Salmonella-specific phages (FelixO1, S16, Sp6, LPST153, and P22 HT105/1 int-201).

Bacteria intrinsic to Medicago sativa (alfalfa) reduce Salmonella enterica growth in planta.

Aims: The purpose of this study was to determine whether plant-associated bacteria (PAB) can reduce Salmonella enterica colonization and infection of alfalfa sprouts to reduce the risk of foodborne illness.

Methods: We isolated PAB from alfalfa seeds and sprouts. Monoclonal isolates of the bacteria were obtained and tested for their ability to inhibit Salmonella Typhimurium growth in alfalfa sprouts over 6 days.

Comparative genome analysis of commensal segmented filamentous bacteria (SFB) from turkey and murine hosts reveals distinct metabolic features.

Background: Segmented filamentous bacteria (SFB) are intestinal commensal microorganisms that have been demonstrated to induce the innate and adaptive immune responses in mouse and rat hosts. SFB are Gram-positive, spore-forming bacteria that fail to grow optimally under in vitro conditions due to unique metabolic requirements. Recently, SFB have been implicated in improved health and growth outcomes in commercial turkey flocks.

Draft Genome Sequence of " Arthromitus" UMNCA01, a Suspected Commensal Isolated from the Gut Microbiome of Commercial Turkey.

" Arthromitus" UMNCA01 was recovered from ileal samples of commercial turkey poults and may have probiotic capabilities. The complete genome was determined using the Illumina MiSeq and HiSeq sequencing platforms. The complete genome consists of 1,631,326 bp and has a G+C content of 26.

Nutritional Status According to the Mini Nutritional Assessment Predicts Speed and Degree of Functional Improvement and Discharge Outcomes in Rehabilitation Patients.

This retrospective observational study evaluated the association between nutritional status, functional ability and discharge outcomes. Data from 1430 older rehabilitation patients (43% male, median age 79 years, interquartile range: 74-84) were analyzed. One fifth (20.

The rsmS (ybaM) mutation causes bypass suppression of the RsmAB post-transcriptional virulence regulation system in enterobacterial phytopathogens.

Plant cell wall degrading enzymes (PCWDEs) are the primary virulence determinants of soft rotting bacteria such as the potato pathogen, Pectobacterium atrosepticum. The regulation of secondary metabolite (Rsm) system controls production of PCWDEs in response to changing nutrient conditions. This work identified a new suppressor of an rsmB mutation - ECA1172 or rsmS (rsmB suppressor).

Evaluation of the impact of a post-hospital discharge Transitional Aged Care Service on frailty, malnutrition and functional ability.

Aim: To investigate the relationship between nutritional status, functional ability and frailty in older adults participating in a 12-week Transitional Aged Care Service program.

Methods: A retrospective analysis of a clinical cohort of older adults aged 65+ years after hospital discharge. At entry into the program and at completion, nutritional status was measured using the Mini Nutritional Assessment (MNA), frailty status was measured using the Groningen Frailty Indicator and functional ability was measured using the Modified Barthel Index (MBI).

Stringent control of FLP recombinase in Escherichia coli.

Site specific recombinases are invaluable tools in molecular biology, and are emerging as powerful recorders of cellular events in synthetic biology. We have developed a stringently controlled FLP recombinase system in Escherichia coli using an arabinose inducible promoter combined with a weak ribosome binding site.

A Comparison of the ATP Generating Pathways Used by S. Typhimurium to Fuel Replication within Human and Murine Macrophage and Epithelial Cell Lines.

The metabolism of S. Typhimurium within infected host cells plays a fundamental role in virulence since it enables intracellular proliferation and dissemination and affects the innate immune response. An essential requirement for the intracellular replication of S.

Toward Network Biology in E. coli Cell.

E. coli has been a critically important model research organism for more than 50 years, particularly in molecular biology. In 1997, the E.

Mep72, a metzincin protease that is preferentially secreted by biofilms of Pseudomonas aeruginosa.

In this work, we compared the profile of proteins secreted by planktonic and biofilm cultures of Pseudomonas aeruginosa using two-dimensional difference gel electrophoresis (2D-DiGE). This revealed that a novel metzincin protease, Mep72, was secreted during biofilm growth. Subsequent Western blotting and reverse transcription-PCR (RT-PCR) analyses demonstrated that Mep72 was expressed only during biofilm growth.

Nutritional and metabolic requirements for the infection of HeLa cells by Salmonella enterica serovar Typhimurium.

Salmonella is the causative agent of a spectrum of human and animal diseases ranging from gastroenteritis to typhoid fever. It is a food--and water--borne pathogen and infects via ingestion followed by invasion of intestinal epithelial cells and phagocytic cells. In this study we employed a mutational approach to define the nutrients and metabolic pathways required by Salmonella enterica serovar Typhimurium during infection of a human epithelial cell line (HeLa).

Surface swarming motility by Pectobacterium atrosepticum is a latent phenotype that requires O antigen and is regulated by quorum sensing.

We describe a previously cryptic phenotype associated with the opportunistic phytopathogen Pectobacterium atrosepticum (Pca): surface swarming. We found that when Pca was spotted onto plates containing <0.5% (w/v) agar, the culture produced copious amounts of extracellular matrix material containing highly motile cells.

Virulence in Pectobacterium atrosepticum is regulated by a coincidence circuit involving quorum sensing and the stress alarmone, (p)ppGpp.

Pectobacterium atrosepticum (Pca) is a Gram-negative phytopathogen which causes disease by secreting plant cell wall degrading exoenzymes (PCWDEs). Previous studies have shown that PCWDE production is regulated by (i) the intercellular quorum sensing (QS) signal molecule, 3-oxo-hexanoyl-l-homoserine lactone (OHHL), and (ii) the intracellular 'alarmone', (p)ppGpp, which reports on nutrient limitation. Here we show that these two signals form an integrated coincidence circuit which ensures that metabolically costly PCWDE synthesis does not occur unless the population is simultaneously quorate and nutrient limited.

Intra-species bacterial quorum sensing studied at single cell level in a double droplet trapping system.

In this paper, we investigated the intra-species bacterial quorum sensing at the single cell level using a double droplet trapping system. Escherichia coli transformed to express the quorum sensing receptor protein, LasR, were encapsulated in microdroplets that were positioned adjacent to microdroplets containing the autoinducer, N-(3-oxododecanoyl)-L-homoserine lactone (OdDHL). Functional activation of the LasR protein by diffusion of the OdDHL across the droplet interface was measured by monitoring the expression of green fluorescent protein (GFP) from a LasR-dependent promoter.

Applications of small molecule activators and inhibitors of quorum sensing in Gram-negative bacteria.

Quorum sensing is a form of intercellular communication used by many species of bacteria that facilitates concerted interactions between the cells comprising a population. The phenotypes regulated by quorum sensing are extremely diverse, with many having a significant impact upon healthcare, agriculture, and the environment. Consequently there has been significant interest in developing methods to manipulate this signalling process and recent years have witnessed significant theoretical and practical developments.

Controlling the contents of microdroplets by exploiting the permeability of PDMS.

A microfluidic device capable of exploiting the permeability of small molecules through polydimethylsiloxane (PDMS) has been fabricated in order to control the contents of microdroplets stored in storage wells. We demonstrate that protein precipitation and crystallization can be triggered by delivery of ethanol from a reservoir channel, thus controlling the protein solubility in microdroplets. Likewise quorum sensing in bacteria was triggered by delivery of the auto-inducer N-(3-oxododecanoyl)-l-homoserine lactone (OdDHL) through the PDMS membrane of the device.

Novel and efficient copper-catalysed synthesis of nitrogen-linked medium-ring biaryls.

Herein, a new copper-catalysed strategy for the synthesis of rare nitrogen-linked seven-, eight- and nine-membered biaryl ring systems is described. It is proposed that the reaction proceeds through a highly activated intramolecularly co-ordinated copper catalyst. The process is technically simple, proceeds under relatively mild conditions, displays a broad substrate scope and forms biologically valuable products that are difficult to synthesise by other methods.