A carotenoid-deficient mutant in Pantoea sp. YR343, a bacteria isolated from the Rhizosphere of Populus deltoides, is defective in root colonization

The complex interactions between plants and their microbiome can have a profound effect on the health and productivity of the plant host. A better understanding of the microbial mechanisms that promote plant health and stress tolerance will enable strategies for improving the productivity of economically important plants. Pantoea sp. YR343 is a motile, rod-shaped bacterium isolated from the roots of Populus deltoides that possesses the ability to solubilize phosphate and produce the phytohormone indole-3-acetic acid (IAA). Pantoea sp. YR343 readily colonizes plant roots and does not appear to be pathogenic when applied to the leaves or roots of selected plant hosts. To better understand the molecular mechanisms involved in plant association and rhizosphere survival by Pantoea sp. YR343, we constructed a mutant in which the crtB gene encoding phytoene synthase was deleted. Phytoene synthase is responsible for converting geranylgeranyl pyrophosphate to phytoene, an important precursor to the production of carotenoids. As predicted, the ΔcrtB mutant is defective in carotenoid production, and shows increased sensitivity to oxidative stress. Moreover, we find that the ΔcrtB mutant is impaired in biofilm formation and production of IAA. Finally we demonstrate that the ΔcrtB mutant shows reduced colonization of plant roots. Taken together, these data suggest that carotenoids are important for plant association and/or rhizosphere survival in Pantoea sp. YR343.Work at the University of Notre Dame was supported by DOE grant SC0006642 (RM) and by a subcontract from Oak Ridge National Laboratory (SP).http://www.frontiersin.orgam2016Microbiology and Plant Patholog

Patient-reported outcomes for diabetes and hypertension care in low- and middle-income countries: A scoping review.

IntroductionPatient-reported outcome measures (PROMs) assess patients' perspectives on their health status, providing opportunities to improve the quality of care. While PROMs are increasingly used in high-income settings, limited data are available on PROMs use for diabetes and hypertension in low-and middle-income countries (LMICs). This scoping review aimed to determine how PROMs are employed for diabetes and hypertension care in LMICs.MethodsWe searched PubMed, EMBASE, and ClinicalTrials.gov for English-language studies published between August 2009 and August 2019 that measured at least one PROM related to diabetes or hypertension in LMICs. Full texts of included studies were examined to assess study characteristics, target population, outcome focus, PROMs used, and methods for data collection and reporting.ResultsSixty-eight studies met the inclusion criteria and reported on PROMs for people diagnosed with hypertension and/or diabetes and receiving care in health facilities. Thirty-nine (57%) reported on upper-middle-income countries, 19 (28%) reported on lower-middle-income countries, 4 (6%) reported on low-income countries, and 6 (9%) were multi-country. Most focused on diabetes (60/68, 88%), while 4 studies focused on hypertension and 4 focused on diabetes/hypertension comorbidity. Outcomes of interest varied; most common were glycemic or blood pressure control (38), health literacy and treatment adherence (27), and acute complications (22). Collectively the studies deployed 55 unique tools to measure patient outcomes. Most common were the Morisky Medication Adherence Scale (7) and EuroQoL-5D-3L (7).ConclusionPROMs are deployed in LMICs around the world, with greatest reported use in LMICs with an upper-middle-income classification. Diabetes PROMs were more widely deployed in LMICs than hypertension PROMs, suggesting an opportunity to adapt PROMs for hypertension. Future research focusing on standardization and simplification could improve future comparability and adaptability across LMIC contexts. Incorporation into national health information systems would best establish PROMs as a means to reveal the effectiveness of person-centered diabetes and hypertension care

Tackling syndemics by integrating infectious and noncommunicable diseases in health systems of low- and middle-income countries: A narrative systematic review.

The co-occurrence of infectious diseases (ID) and non-communicable diseases (NCD) is widespread, presenting health service delivery challenges especially in low-and middle-income countries (LMICs). Integrated health care is a possible solution but may require a paradigm shift to be successfully implemented. This literature review identifies integrated care examples among selected ID and NCD dyads. We searched PubMed, PsycINFO, Cochrane Library, CINAHL, Web of Science, EMBASE, Global Health Database, and selected clinical trials registries. Eligible studies were published between 2010 and December 2022, available in English, and report health service delivery programs or policies for the selected disease dyads in LMICs. We identified 111 studies that met the inclusion criteria, including 56 on tuberculosis and diabetes integration, 46 on health system adaptations to treat COVID-19 and cardiometabolic diseases, and 9 on COVID-19, diabetes, and tuberculosis screening. Prior to the COVID-19 pandemic, most studies on diabetes-tuberculosis integration focused on clinical service delivery screening. By far the most reported health system outcomes across all studies related to health service delivery (n = 72), and 19 addressed health workforce. Outcomes related to health information systems (n = 5), leadership and governance (n = 3), health financing (n = 2), and essential medicines (n = 4)) were sparse. Telemedicine service delivery was the most common adaptation described in studies on COVID-19 and either cardiometabolic diseases or diabetes and tuberculosis. ID-NCD integration is being explored by health systems to deal with increasingly complex health needs, including comorbidities. High excess mortality from COVID-19 associated with NCD-related comorbidity prompted calls for more integrated ID-NCD surveillance and solutions. Evidence of clinical integration of health service delivery and workforce has grown-especially for HIV and NCDs-but other health system building blocks, particularly access to essential medicines, health financing, and leadership and governance, remain in disease silos

MALDI-guided SIMS: Multiscale Imaging of Metabolites in Bacterial Biofilms

Mass spectrometry imaging (MSI) is a versatile tool for visualizing molecular distributions in complex biological specimens, but locating microscopic chemical features of interest can be challenging in samples that lack a well-defined anatomy. To address this issue, we developed a correlated imaging approach that begins with performing matrix-assisted laser desorption/ionization (MALDI) MSI to obtain low-resolution molecular maps of a sample. The resulting maps are then used to direct subsequent microscopic secondary ion mass spectrometry (SIMS) imaging and tandem mass spectrometry (MS/MS) experiments to examine selected chemical regions of interest. By employing MALDI undersampling, the sample surface is left mostly unperturbed and available for the SIMS analysis, while also generating an ablation array that can be used for navigation in SIMS. We validated this MALDI-guided SIMS approach using cultured biofilms of the opportunistic pathogen Pseudomonas aeruginosa; bioactive secondary metabolites, including rhamnolipids and quinolones, were detected and visualized on both macro- and microscopic size scales. MSI mass assignments were confirmed with in situ MALDI MS/MS and capillary electrophoresis–electrospray ionization MS/MS analysis of biofilm extracts. Two strains of P. aeruginosa were compared, wild type and a quorum sensing mutant, and differences in metabolite abundance and distribution were observed

Correlated Imaging with C₆₀-SIMS and Confocal Raman Microscopy: Visualization of Cell-Scale Molecular Distributions in Bacterial Biofilms

Secondary ion mass spectrometry (SIMS) and confocal Raman microscopy (CRM) are combined to analyze the chemical composition of cultured <i>Pseudomonas aeruginosa</i> biofilms, providing complementary chemical information for multiple analytes within the sample. Precise spatial correlation between SIMS and CRM images is achieved by applying a chemical microdroplet array to the sample surface which is used to navigate the sample, relocate regions of interest, and align image data. CRM is then employed to nondestructively detect broad molecular constituent classesincluding proteins, carbohydrates, and, for the first time, quinolone signaling moleculesin <i>Pseudomonas</i>-derived biofilms. Subsequent SIMS imaging at the same location detects quinolone distributions in excellent agreement with the CRM, discerns multiple quinolone species which differ slightly in mass, resolves subtle differences in their distributions, and resolves ambiguous compound assignments from CRM by determining specific molecular identities via <i>in situ</i> tandem MS