Bacteriophages fEV-1 and fD1 Infect Yersinia pestis

Bacteriophages vB_YpeM_fEV-1 (fEV-1) and vB_YpeM_fD1 (fD1) were isolated from incoming sewage water samples in Turku, Finland, using Yersinia pestis strains EV76 and KIM D27 as enrichment hosts, respectively. Genomic analysis and transmission electron microscopy established that fEV-1 is a novel type of dwarf myovirus, while fD1 is a T4-like myovirus. The genome sizes are 38 and 167 kb, respectively. To date, the morphology and genome sequences of some dwarf myoviruses have been described; however, a proteome characterization such as the one presented here, has currently been lacking for this group of viruses. Notably, fEV-1 is the first dwarf myovirus described for Y. pestis. The host range of fEV-1 was restricted strictly to Y. pestis strains, while that of fD1 also included other members of Enterobacterales such as Escherichia coli and Yersinia pseudotuberculosis. In this study, we present the life cycles, genomes, and proteomes of two Yersinia myoviruses, fEV-1 and fD1

Bacteriophages fEV-1 and fD1 Infect Yersinia pestis

Bacteriophages vB_YpeM_fEV-1 (fEV-1) and vB_YpeM_fD1 (fD1) were isolated from incoming sewage water samples in Turku, Finland, using Yersinia pestis strains EV76 and KIM D27 as enrichment hosts, respectively. Genomic analysis and transmission electron microscopy established that fEV-1 is a novel type of dwarf myovirus, while fD1 is a T4-like myovirus. The genome sizes are 38 and 167 kb, respectively. To date, the morphology and genome sequences of some dwarf myoviruses have been described; however, a proteome characterization such as the one presented here, has currently been lacking for this group of viruses. Notably, fEV-1 is the first dwarf myovirus described for Y. pestis. The host range of fEV-1 was restricted strictly to Y. pestis strains, while that of fD1 also included other members of Enterobacterales such as Escherichia coli and Yersinia pseudotuberculosis. In this study, we present the life cycles, genomes, and proteomes of two Yersinia myoviruses, fEV-1 and fD1

Prophages and Past Prophage-Host Interactions Revealed by CRISPR Spacer Content in a Fish Pathogen

The role of prophages in the evolution, diversification, or virulence of the fish pathogen Flavobacterium columnare has not been studied thus far. Here, we describe a functional spontaneously inducing prophage fF4 from the F. columnare type strain ATCC 23463, which is not detectable with commonly used prophage search methods. We show that this prophage type has a global distribution and is present in strains isolated from Finland, Thailand, Japan, and North America. The virions of fF4 are myoviruses with contractile tails and infect only bacterial strains originating from Northern Finland. The fF4 resembles transposable phages by similar genome organization and several gene orthologs. Additional bioinformatic analyses reveal several species in the phylum Bacteroidetes that host a similar type of putative prophage, including bacteria that are important animal and human pathogens. Furthermore, a survey of F. columnare Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) spacers indicate a shared evolutionary history between F. columnare strains and the fF4 phage, and another putative prophage in the F. columnare strain ATCC 49512, named p49512. First, CRISPR spacer content from the two CRISPR loci (types II-C and VI-B) of the fF4 lysogen F. columnare ATCC 23463 revealed a phage terminase protein-matching spacer in the VI-B locus. This spacer is also present in two Chinese F. columnare strains. Second, CRISPR analysis revealed four F. columnare strains that contain unique spacers targeting different regions of the putative prophage p49512 in the F. columnare strain ATCC 49512, despite the geographical distance or genomovar of the different strains. This suggests a common ancestry for the F. columnare prophages and different host strains

Adenosine triphosphatases of thermophilic archaeal double-stranded DNA viruses

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Supergravity origin of the MSSM inflation

We consider the supergravity origin of the recently proposed MSSM inflationary model, which relies on the existence of a saddle point along a dimension six flat direction. We derive the conditions that the Kahler potential has to satisfy for the saddle point to exist irrespective of the hidden sector vevs. We show that these conditions are satisfied by a simple class of Kahler potentials, which we find to have a similar form as in various string theory compactifications. For these potentials, slow roll MSSM inflation requires no fine tuning of the soft supersymmetry breaking parameters.Comment: v3: 10 pages, no figures; version accepted for publication. Typos correcte

A Case Study of Three Swedish Hospitals’ Strategies for Implementing Lean Production

Many hospitals have recently implemented the management concept lean production. The aim of this study was to learn how and why three Swedish hospitals selected and developed their hospitalwide lean production strategies. Although previous research shows that the concept is implemented in various ways, there is limited research on how and why different hospitals choose different implementation strategies and if the chosen strategies contribute to sustainable participation in organizational development. A case study of three different Swedish hospitals implementing lean production was thus performed. We studied the content of the hospitals’ selected implementation strategies, conditions and rationales behind their strategy selection, and how different organizational actors participated in the implementation. Qualitative interviews with 54 key actors at the studied hospitals were performed. In addition, a self-administered survey questionnaire to employees was answered at T1 (2012, n = 557), T2 (2013, n = 554), and T3 (2014, n = 366). The three studied hospitals chose different strategies for implementing lean production due to different contextual conditions and for different reasons. The hospital-wide implementation strategies were related to employees’ interest and participation in lean production. The results show that many different actors at different organizational levels need to participate in lean production in order to sustain and diffuse change processes. Furthermore, broad motives including quality of care seem to be needed for engaging different professional groups

Managerial Practices that Support Lean and Socially Sustainable Working Conditions

Despite decades of using lean, there is little knowledge of how lean managerial practices affect working conditions. Thus, the aim of this study was to investigate in what ways managerial practices support socially sustainable working conditions (SSWCs) during a lean transformation. A mixed methods approach was used in this multiyear case study in a midsize Swedish manufacturing company. Assessment of work characteristics was combined with employee questionnaires and interviews with managers. Four practices were identified as instrumental for SSWCs: 1) a coherent lean approach with clear direction, 2) a value-creating leadership style comprising a participatorypromoting and caring leadership approach with joint focus on production and well-being, 3) conscious involvement of employees in a stepwise fashion, and 4) a focus on promoting meaningful jobs and health, aided by work environment management. Thus, managerial practices actively supporting important job resources as an integral part of the lean system seemed to support SSWCs

Macular edema after cataract surgery in eyes with and without pseudoexfoliation syndrome

Background: The purpose of the study was to identify macular edema after cataract surgery in eyes with and without pseudoexfoliation syndrome. The study was a post-hoc analysis of a randomized, double-blind, prospective single-center study. Patients were enrolled between January 2016 and October 2016 as per the national guidelines for the management of cataract in the Department of Ophthalmology, Kymenlaakso Central Hospital, Kotka, Finland. Methods: One hundred and fifty-six eyes of 149 patients undergoing routine cataract surgery. Postoperatively anti-inflammatory medication was either dexamethasone (N = 78) or diclofenac (N = 78). Spectral domain optical coherence tomography imaging and laser flare meter measurement of the anterior chamber were conducted before surgery and at the control visit 28 days postoperatively. Results: Baseline variables were comparable between eyes with pseudoexfoliation syndrome (N = 32) and those without (N = 124), except for intraocular pressure (P = 0.002) and glaucoma medication (P <0.001). In patients having pseudoexfoliation syndrome, central retinal thickness increase (mean +/- standard error of the mean) was 63.3 +/- 35.5 mu m for dexamethasone and 17.6 +/- 5.8 mu m for diclofenac, compared to 28.9 +/- 8.0 mu m (P = NS) and 6.9 +/- 1.3 mu m (P = 0.014) in eyes without pseudoexfoliation syndrome, respectively. Aqueous flare at 28 days was 25.8 +/- 5.4 pu/ms for patients with pseudoexfoliation syndrome and 18.3 +/- 1.8 pu/ms for those without (P = 0.030). Best corrected visual acuity gain and best corrected visual acuity at 28 days were less in patients having pseudoexfoliation syndrome compared to those without (0.39 +/- 0.07 vs 0.59 +/- 0.03 decimals, P = 0.007; and 0.77 +/- 0.06 vs 0.92 +/- 0.03 decimals, P = 0.008, respectively). Conclusion: Eyes with pseudoexfoliation syndrome may be predisposed to an increased aqueous flare and macular edema after cataract surgery. This study outlines the need to determine the optimal anti-inflammatory medication after cataract surgery in patients with pseudoexfoliation syndrome.Peer reviewe

BtuB-Dependent Infection of the T5-like Yersinia Phage phi R2-01

Yersinia enterocolitica is a food-borne Gram-negative pathogen responsible for several gastrointestinal disorders. Host-specific lytic bacteriophages have been increasingly used recently as an alternative or complementary treatment to combat bacterial infections, especially when antibiotics fail. Here, we describe the proteogenomic characterization and host receptor identification of the siphovirus vB_YenS_phi R2-01 (in short, phi R2-01) that infects strains of several Yersinia enterocolitica serotypes. The phi R2-01 genome contains 154 predicted genes, 117 of which encode products that are homologous to those of Escherichia bacteriophage T5. The phi R2-01 and T5 genomes are largely syntenic, with the major differences residing in areas encoding hypothetical phi R2-01 proteins. Label-free mass-spectrometry-based proteomics confirmed the expression of 90 of the phi R2-01 genes, with 88 of these being either phage particle structural or phage-particle-associated proteins. In vitro transposon-based host mutagenesis and phi R2-01 adsorption experiments identified the outer membrane vitamin B12 receptor BtuB as the host receptor. This study provides a proteogenomic characterization of a T5-type bacteriophage and identifies specific Y. enterocolitica strains sensitive to infection with possible future applications of phi R2-01 as a food biocontrol or phage therapy agent.Peer reviewe