Phage Milagro: a platform for engineering a broad host range virulent phage for Burkholderia.

IMPORTANCE: Burkholderia infections are a significant concern in people with CF and other immunocompromising disorders, and are difficult to treat with conventional antibiotics due to their inherent drug resistance. Bacteriophages, or bacterial viruses, are now seen as a potential alternative therapy for these infections, but most of the naturally occurring phages are temperate and have narrow host ranges, which limit their utility as therapeutics. Here we describe the temperate Burkholderia phage Milagro and our efforts to engineer this phage into a potential therapeutic by expanding the phage host range and selecting for phage mutants that are strictly virulent. This approach may be used to generate new therapeutic agents for treating intractable infections in CF patients.

Therapeutic Potential of Intravenous Phage as Standalone Therapy for Recurrent Drug-Resistant Urinary Tract Infections.

Recurrent urinary tract infections (rUTI) are common in kidney transplant recipients (KTR) and are associated with multidrug resistance and increased morbidity/mortality. Novel antibiotic alternatives to reduce UTI recurrence are critically needed. We describe a case of rUTI due to extended spectrum beta lactamase (ESBL) Klebsiella pneumoniae in a KTR that was treated successfully with 4 weeks of adjunctive intravenous bacteriophage therapy alone, without concomitant antibiotics, and with no recurrence in a year of follow-up.

Adaptable Multivalent Hairy Inorganic Nanoparticles.

We report a polymer brush-based approach for fabricating multivalent patchy nanoparticles (NPs) with the number of nanodomains (valency) from 6 to 10, potentially from 1 to 10, by exploiting the lateral microphase separation of binary mixed homopolymer brushes grafted on NPs with a radius comparable to the polymer sizes. Well-defined mixed brushes were grown on 20.4 nm silica NPs by two-step surface-initiated reversible deactivation radical polymerizations and microphase separated laterally upon casting from a good solvent, producing multivalent NPs on 2D surfaces. A linear relationship between valency and average core size for the corresponding valency was observed. The mixed brush NPs exhibited abilities to form "bonds" through the overlap of nanodomains and to change the valency when interacting with adjacent NPs. This method could open up a new avenue for studying patchy NPs.

A Broad-Host-Range Tailocin from Burkholderia cenocepacia.

The Burkholderia cepacia complex (Bcc) consists of 20 closely related Gram-negative bacterial species that are significant pathogens for persons with cystic fibrosis (CF). Some Bcc strains are highly transmissible and resistant to multiple antibiotics, making infection difficult to treat. A tailocin (phage tail-like bacteriocin), designated BceTMilo, with a broad host range against members of the Bcc, was identified in B. cenocepacia strain BC0425. Sixty-eight percent of Bcc representing 10 species and 90% of non-Bcc Burkholderia strains tested were sensitive to BceTMilo. BceTMilo also showed killing activity against Pseudomonas aeruginosa PAO1 and derivatives. Liquid chromatography-mass spectrometry analysis of the major BceTMilo proteins was used to identify a 23-kb tailocin locus in a draft BC0425 genome. The BceTMilo locus was syntenic and highly similar to a 24.6-kb region on chromosome 1 of B. cenocepacia J2315 (BCAL0081 to BCAL0107). A close relationship and synteny were observed between BceTMilo and Burkholderia phage KL3 and, by extension, with paradigm temperate myophage P2. Deletion mutants in the gene cluster encoding enzymes for biosynthesis of lipopolysaccharide (LPS) in the indicator strain B. cenocepacia K56-2 conferred resistance to BceTMilo. Analysis of the defined mutants in LPS biosynthetic genes indicated that an α-d-glucose residue in the core oligosaccharide is the receptor for BceTMilo.IMPORTANCE BceTMilo, presented in this study, is a broad-host-range tailocin active against Burkholderia spp. As such, BceTMilo and related or modified tailocins have potential as bactericidal therapeutic agents against plant- and human-pathogenic Burkholderia.

Photodynamic treatment increases the lifespan and oxidative stress resistance of Caenorhabditis elegans.

Photodynamic therapy is a noninvasive treatment in which specific photosensitizers and light are used to produce high amounts of reactive oxygen species (ROS), which can be employed for targeted tissue destruction in cancer treatment or antimicrobial therapy. However, it remains unknown whether lower amounts of ROS produced by mild photodynamic therapy increase lifespan and stress resistance at the organism level. Here, we introduce a novel photodynamic treatment (PDTr) that uses 20 µM hypericin, a photosensitizer that originates from Hypericum perforatum, and orange light (590 nm, 5.4 W/m2, 1 min) to induce intracellular ROS formation (ROS), thereby resulting in lifespan extension and improved stress resistance in C. elegans. The PDTr-induced increase in longevity was abrogated by N-acetyl cysteine, suggesting the hormetic response was driven by prooxidative mechanisms. PDTr activated the translocation of SKN-1/NRF-2 and DAF-16/FOXO, leading to elevated expression of downstream oxidative stress-responsive genes, including ctl-1, gst-4, and sod-3. In summary, our findings suggest a novel PDTr method that extends the lifespan of C. elegans under both normal and oxidative stress conditions through the activation of SKN-1 and DAF-16 via the involvement of many antioxidant genes.

Assessment of availability, readiness, and challenges for scaling-up hypertension management services at primary healthcare facilities, Central Highland region, Vietnam, 2020.

INTRODUCTION: Vietnam aims for 95% of commune health stations (CHSs) to have functional hypertension management programs by 2025. However, limited resources may impede the Central Highland region health system from achieving this goal. We assessed the availability and readiness of hypertension management services at CHSs in the Central Highland region and identified challenges to facilitate evidence-based planning. METHODS: We used a mixed-methods cross-sectional design to assess hypertension management services using WHO's service availability and readiness assessment (SARA) tools in all 579 CHSs in the region, combined with twenty in-depth interviews of hypertension program focal points at communal, district, and provincial levels in all four provinces. We descriptively analyzed quantitative data and thematically analyzed qualitative data. RESULTS: Hypertension management services were available at 65% of CHSs, and the readiness of the services was 62%. The urban areas had higher availability and readiness indices in most domains (basic amenities, basic equipment, and essential medicines) compared to rural areas, except for staff and training. The qualitative results showed a lack of trained staff and ambiguity in national hypertension treatment guidelines, insufficient essential medicines supply mechanism, and low priority and funding limitations for the hypertension program. CONCLUSION: The overall availability and readiness for hypertension diagnosis and management service at CHSs in the Central Highland region were low, reflecting inadequate capacity of the primary healthcare facilities. Some measures to strengthen hypertension programs in the region might include increased financial support, ensuring a sufficient supply of basic medicines, and providing more specific treatment guidelines.

Competitive interference among rhizobia reduces benefits to hosts.

The capacity of beneficial microbes to compete for host infection-and the ability of hosts to discriminate among them-introduces evolutionary conflict that is predicted to destabilize mutualism. We investigated fitness outcomes in associations between legumes and their symbiotic rhizobia to characterize fitness impacts of microbial competition. Diverse Bradyrhizobium strains varying in their capacity to fix nitrogen symbiotically with a common host plant, Acmispon strigosus, were tested in full-factorial coinoculation experiments involving 28 pairwise strain combinations. We analyzed the effects of interstrain competition and host discrimination on symbiotic-interaction outcomes by relativizing fitness proxies to clonally infected and uninfected controls. More than one thousand root nodules of coinoculated plants were genotyped to quantify strain occupancy, and the Bradyrhizobium strain genome sequences were analyzed to uncover the genetic bases of interstrain competition outcomes. Strikingly, interstrain competition favored a fast-growing, minimally beneficial rhizobia strain. Host benefits were significantly diminished in coinoculation treatments relative to expectations from clonally inoculated controls, consistent with competitive interference among rhizobia that reduced both nodulation and plant growth. Competition traits appear polygenic, linked with inter-strain allelopathic interactions in the rhizosphere. This study confirms that competition among strains can destabilize mutualism by favoring microbes that are superior in colonizing host tissues but provide minimal benefits to host plants. Moreover, our findings help resolve the paradox that despite efficient host control post infection, legumes nonetheless encounter rhizobia that vary in their nitrogen fixation.

An Experimental Field Trial Investigating the Use of Bacteriophage and Manure Slurry Applications in Beef Cattle Feedlot Pens for Salmonella Mitigation.

Post-harvest Salmonella mitigation techniques are insufficient at addressing Salmonella harbored in cattle lymph nodes, necessitating the exploration of pre-harvest alternatives that reduce Salmonella prior to dissemination to the lymph nodes. A 2 × 2, unbalanced experiment was conducted to determine the effectiveness of pre-harvest treatments applied to the pen surface for Salmonella mitigation in cattle. Treatments included manure slurry intended to mimic pen run-off water (n = 4 pens), a bacteriophage cocktail (n = 4), a combination of both treatments (n = 5), and a control group (n = 5) that received no treatment. Environment samples from 18 feedlot pens and fecal grabs, hide swabs, and subiliac lymph nodes from 178 cattle were collected and selectively enriched for Salmonella, and Salmonella isolates were sequenced. The combination treatment was most effective at reducing Salmonella, and the prevalence was significantly lower compared with the control group for rump swabs on Days 14 and 21. The treatment impact on Salmonella in the lymph nodes could not be determined due to low prevalence. The reduction on cattle hides suggests that bacteriophage or water treatments applied to the feedlot pen surface may reduce Salmonella populations in cattle during the pre-harvest period, resulting in reduced contamination during slaughter and processing.

Compounding Achromobacter Phages for Therapeutic Applications.

Achromobacter species colonization of Cystic Fibrosis respiratory airways is an increasing concern. Two adult patients with Cystic Fibrosis colonized by Achromobacter xylosoxidans CF418 or Achromobacter ruhlandii CF116 experienced fatal exacerbations. Achromobacter spp. are naturally resistant to several antibiotics. Therefore, phages could be valuable as therapeutics for the control of Achromobacter. In this study, thirteen lytic phages were isolated and characterized at the morphological and genomic levels for potential future use in phage therapy. They are presented here as the Achromobacter Kumeyaay phage collection. Six distinct Achromobacter phage genome clusters were identified based on a comprehensive phylogenetic analysis of the Kumeyaay collection as well as the publicly available Achromobacter phages. The infectivity of all phages in the Kumeyaay collection was tested in 23 Achromobacter clinical isolates; 78% of these isolates were lysed by at least one phage. A cryptic prophage was induced in Achromobacter xylosoxidans CF418 when infected with some of the lytic phages. This prophage genome was characterized and is presented as Achromobacter phage CF418-P1. Prophage induction during lytic phage preparation for therapy interventions require further exploration. Large-scale production of phages and removal of endotoxins using an octanol-based procedure resulted in a phage concentrate of 1 × 109 plaque-forming units per milliliter with an endotoxin concentration of 65 endotoxin units per milliliter, which is below the Food and Drugs Administration recommended maximum threshold for human administration. This study provides a comprehensive framework for the isolation, bioinformatic characterization, and safe production of phages to kill Achromobacter spp. in order to potentially manage Cystic Fibrosis (CF) pulmonary infections.

Herb-drug Interactions in Neuropsychiatric Pharmacotherapy - A Review of Clinically Relevant Findings.

The management of neuropsychiatric disorders relies heavily on pharmacotherapy. The use of herbal products as complimentary medicine, often concomitantly, is common among patients taking prescription neuropsychiatric drugs. Herb-drug interaction, a clinical consequence of this practice, may jeopardize the success of pharmacotherapy in neuropsychiatry. Besides the wellknown ability of phytochemicals to inhibit and/or induce drug-metabolizing enzymes and transport proteins, several phytoconstituents are capable of exerting pharmacological effects on the central nervous system. This study reviewed the relevant literature and identified 13 commonly used herbal products - celery, echinacea, ginkgo, ginseng, hydroxycut, kava, kratom, moringa, piperine, rhodiola, St. John's wort, terminalia/commiphora ayurvedic mixture and valerian - which have shown clinically relevant interactions with prescription drugs used in the management of neuropsychiatric disorders. The consequent pharmacokinetic and pharmacodynamic interactions with orthodox medications often result in deleterious clinical consequences. This underscores the importance of caution in herb-drug co-medication.

Complete Genome Sequence of Stenotrophomonas maltophilia Siphophage Sonora.

Phage Sonora is a siphophage that was isolated against the opportunistic human pathogen Stenotrophomonas maltophilia. The genome of phage Sonora is 63,825 bp long and is not related to that of any phage at the nucleotide level. Sonora shares 46 of 97 total proteins with the Bordetella phages CN2, MW2, and FP1.

Complete Genome Sequence of Stenotrophomonas maltophilia Phage Philippe.

Stenotrophomonas maltophilia is emerging as an opportunistic multidrug-resistant pathogen. S. maltophilia podophage Philippe has a 74,717-bp genome which is related broadly to the N4-like phage group, including Stenotrophomonas phage Pokken. The low sequence identity to other described phages suggests that Philippe is an unclassified member of the N4-like subfamily Rothmandenesvirinae.

Complete Genome Sequence of Stenotrophomonas maltophilia Siphophage Siara.

Stenotrophomonas maltophilia is associated with an increasing incidence of nosocomial infections. Here, we describe the isolation and genome annotation of S. maltophilia siphophage Siara. Its 61,427-bp genome is currently related only to one phage in the NCBI database, namely, S. maltophilia phage Salva, and is not related to any prophages.

Complete Genome Sequence of Stenotrophomonas maltophilia Podophage Pepon.

Stenotrophomonas maltophilia is an opportunistic bacterium that is commonly associated with respiratory infections in immunocompromised patients, including cystic fibrosis patients. In this report, we introduce the complete genome sequence of S. maltophilia podophage Pepon, which is a T7-like phage closely related to the previously reported phage Ponderosa.

Complete Genome Sequence of Stenotrophomonas maltophilia Siphophage Summit.

Stenotrophomonas maltophilia is an opportunistic pathogen exhibiting resistance to multiple antimicrobials. This study reports the complete genome of an S. maltophilia siphophage, Summit. Its genome of 95,728 bp has 148 protein-coding genes and 5 tRNAs, including 1 predicted suppressor tRNA. Possible target genes for the suppressor tRNA are not identified.

Complete Genome Sequence of Stenotrophomonas maltophilia Siphophage Silvanus.

Stenotrophomonas maltophilia is an opportunistic Gram-negative bacterium capable of causing respiratory infections. S. maltophilia siphophage Silvanus was isolated, and its 45,678-bp genome is not closely related to known phages based on whole-genome comparative genomics analysis. It is predicted to use cos-type packaging due to the similarity of its large terminase subunit to that of phage HK97.

Complete Genome Sequence of Stenotrophomonas maltophilia Podophage Piffle.

Stenotrophomonas maltophilia is an emerging multidrug-resistant opportunistic human pathogen causing various nosocomial infections. Here, we characterize the genome of S. maltophilia podophage Piffle. Its 76,332-bp genome is most closely related to the N4-like S. maltophilia podophage Pokken, with over 86% genome-wide nucleotide identity and 84 shared proteins.

Complete Genome Sequence of Burkholderia cenocepacia Phage Paku.

Burkholderia cenocepacia is able to cause infections in cystic fibrosis patients. B. cenocepacia phage Paku has a 42,727-bp genome sharing a phiKMV-like genome arrangement. T7-like tail components were identified in parallel with a tyrosine integrase, suggesting that Paku might exhibit a temperate lifestyle, an atypical feature for an Autographiviridae phage.

Complete Genome Sequence of Enterococcus faecalis Siphophage Sigurd.

Enterococcus faecalis is associated with antibiotic-resistant infections, and this study presents E. faecalis siphophage Sigurd. The 41,811-bp Sigurd genome is divided into two arms defined by long convergent predicted transcription units that are separated by a bidirectional rho-independent terminator. Sigurd has a small terminase that is closely related to Bacillus subtilis cos phage phi105.

Complete Genome Sequence of Stenotrophomonas maltophilia Siphophage Suso.

Phage Suso is a temperate siphophage of Stenotrophomonas maltophilia with a 44,659-bp genome. This phage is closely related to Stenotrophomonas phage SM171, sharing 92% overall nucleotide identity as determined by BLASTn, and it shares 14 similar proteins (BLASTp, E value < 0.001) with some Pseudomonas phages from the genus Beetrevirus.