Marine macroalgae and their associated microbiomes as a source of antimicrobial chemical diversity

© 2017 British Phycological Society. This article reviews the role of microbial biofilms in infection, and the antimicrobial chemical diversity of marine macroalgae and their associated microbiomes. Antimicrobial resistance (AMR) represents one of the major health threats faced by humanity over the next few years. To prevent a global epidemic of antimicrobial-resistant infections, the discovery of new antimicrobials and antibiotics, better anti-infection strategies and diagnostics, and changes to our current use of antibiotics have all become of paramount importance. Numerous studies investigating the bioactivities of seaweed extracts as well as their secondary and primary metabolites highlight the vast biochemical diversity of seaweeds, with new modes of action making them ideal sources for the discovery of novel antimicrobial bioactive compounds of pharmaceutical interest. In recent years, researchers have focused on characterizing the endophytic and epiphytic microbiomes of various algal species in an attempt to elucidate host-microbe interactions as well as to understand the function of microbial communities. Although environmental and host-associated factors crucially shape microbial composition, microbial mutualistic and obligate symbionts are often found to play a fundamental role in regulating many aspects of host fitness involving ecophysiology and metabolism. In particular, algal ‘core’ epiphytic bacterial communities play an important role in the protection of surfaces from biofouling, pathogens and grazers through the production of bioactive metabolites. Together, marine macroalgae and their associated microbiomes represent unique biological systems offering great potential for the isolation and identification of novel compounds and strategies to counteract the rise and dissemination of AMR

Search for jet extinction in the inclusive jet-pT spectrum from proton-proton collisions at s=8 TeV

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.The first search at the LHC for the extinction of QCD jet production is presented, using data collected with the CMS detector corresponding to an integrated luminosity of 10.7  fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The extinction model studied in this analysis is motivated by the search for signatures of strong gravity at the TeV scale (terascale gravity) and assumes the existence of string couplings in the strong-coupling limit. In this limit, the string model predicts the suppression of all high-transverse-momentum standard model processes, including jet production, beyond a certain energy scale. To test this prediction, the measured transverse-momentum spectrum is compared to the theoretical prediction of the standard model. No significant deficit of events is found at high transverse momentum. A 95% confidence level lower limit of 3.3 TeV is set on the extinction mass scale

Searches for electroweak neutralino and chargino production in channels with Higgs, Z, and W bosons in pp collisions at 8 TeV

Searches for supersymmetry (SUSY) are presented based on the electroweak pair production of neutralinos and charginos, leading to decay channels with Higgs, Z, and W bosons and undetected lightest SUSY particles (LSPs). The data sample corresponds to an integrated luminosity of about 19.5 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV collected in 2012 with the CMS detector at the LHC. The main emphasis is neutralino pair production in which each neutralino decays either to a Higgs boson (h) and an LSP or to a Z boson and an LSP, leading to hh, hZ, and ZZ states with missing transverse energy (E-T(miss)). A second aspect is chargino-neutralino pair production, leading to hW states with E-T(miss). The decays of a Higgs boson to a bottom-quark pair, to a photon pair, and to final states with leptons are considered in conjunction with hadronic and leptonic decay modes of the Z and W bosons. No evidence is found for supersymmetric particles, and 95% confidence level upper limits are evaluated for the respective pair production cross sections and for neutralino and chargino mass values

Large-scale characterization of hospital wastewater system microbiomes and clinical isolates from infected patients: profiling of multi-drug-resistant microbial species

BackgroundHospital-acquired infections (HAIs) and infectious agents exhibiting antimicrobial resistance (AMR) are challenges globally. Environmental patient-facing wastewater apparatus including handwashing sinks, showers and toilets are increasingly identified as sources of infectious agents and AMR genes.AimTo provide large-scale metagenomics analysis of wastewater systems in a large teaching hospital in the Republic of Ireland experiencing multi-drug-resistant HAI outbreaks.MethodsWastewater pipe sections (N=20) were removed immediately prior to refurbishment of a medical ward where HAIs had been endemic. These comprised toilet U-bends, and sink and shower drains. Following DNA extraction, each pipe section underwent metagenomic analysis.FindingsDiverse taxonomic and resistome profiles were observed, with members of phyla Proteobacteria and Actinobacteria dominating (38.23 ± 5.68% and 15.78 ± 3.53%, respectively). Genomes of five clinical isolates were analysed. These AMR bacterial isolates were from patients >48 h post-admission to the ward. Genomic analysis determined that the isolates bore a high number of antimicrobial resistance genes (ARGs).ConclusionComparison of resistome profiles of isolates and wastewater metagenomes revealed high degrees of similarity, with many identical ARGs shared, suggesting probable acquisition post-admission. The highest numbers of ARGs observed were those encoding resistance to clinically significant and commonly used antibiotic classes. Average nucleotide identity analysis confirmed the presence of highly similar or identical genomes in clinical isolates and wastewater pipes. These unique large-scale analyses reinforce the need for regular cleaning and decontamination of patient-facing hospital wastewater pipes and effective infection control policies to prevent transmission of nosocomial infection and emergence of AMR within potential wastewater reservoirs.</p