26 research outputs found

    Emergence of novel methicillin resistant Staphylococcus pseudintermedius lineages revealed by whole genome sequencing of isolates from companion animals and humans in Scotland

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    Staphylococcus pseudintermedius is an opportunistic pathogen in dogs, and infection in humans is increasingly found, often linked to contact with dogs. We conducted a retrospective genotyping and antimicrobial susceptibility testing study of 406 S. pseudintermedius isolates cultured from animals (dogs, cats and an otter) and humans across Scotland, from 2007 to 2020. Seventy-five sequence types (STs) were identified, among the 130 isolates genotyped, with 59 seen only once. We observed the emergence of two methicillin resistant Staphylococcus pseudintermedius (MRSP) clones in Scotland: ST726, a novel locally-evolving clone, and ST551, first reported in 2015 in Poland, possibly linked to animal importation to Scotland from Central Europe. While ST71 was the most frequent S. pseudintermedius strain detected, other lineages that have been replacing ST71 in other countries, in addition to ST551, were detected. Multidrug resistance (MDR) was detected in 96.4% of MRSP and 8.4% of MSSP. A single MRSP isolate was resistant to mupirocin. Continuous surveillance for the emergence and dissemination of novel MDR MRSP in animals and humans and changes in antimicrobial susceptibility in S. pseudintermedius is warranted to minimise the threat to animal and human health

    Emergence of novel methicillin resistant Staphylococcus pseudintermedius lineages revealed by whole genome sequencing of isolates from companion animals and humans in Scotland

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    Staphylococcus pseudintermedius is an opportunistic pathogen in dogs, and infection in humans is increasingly found, often linked to contact with dogs. We conducted a retrospective genotyping and antimicrobial susceptibility testing study of 406 S. pseudintermedius isolates cultured from animals (dogs, cats and an otter) and humans across Scotland, from 2007 to 2020. Seventy-five sequence types (STs) were identified, among the 130 isolates genotyped, with 59 seen only once. We observed the emergence of two methicillin resistant Staphylococcus pseudintermedius (MRSP) clones in Scotland: ST726, a novel locally-evolving clone, and ST551, first reported in 2015 in Poland, possibly linked to animal importation to Scotland from Central Europe. While ST71 was the most frequent S. pseudintermedius strain detected, other lineages that have been replacing ST71 in other countries, in addition to ST551, were detected. Multidrug resistance (MDR) was detected in 96.4% of MRSP and 8.4% of MSSP. A single MRSP isolate was resistant to mupirocin. Continuous surveillance for the emergence and dissemination of novel MDR MRSP in animals and humans and changes in antimicrobial susceptibility in S. pseudintermedius is warranted to minimise the threat to animal and human health

    The spatial organization and microbial community structure of an epilithic biofilm.

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    Microbial biofilms are common on lithic surfaces, including stone buildings. However, the ecology of these communities is poorly understood. Few studies have focused on the spatial characteristics of lithobiontic biofilms, despite the fact that spatial structure has been demonstrated to influence ecosystem function (and hence biodegradation) and community diversity. Furthermore, relatively few studies have utilized molecular techniques to characterize these communities, even though molecular methods have revealed unexpected microbial diversity in other habitats. This study investigated (1) the spatial structure and (2) the taxonomic composition of an epilithic biofilm using molecular techniques, namely amplicon pyrosequencing and terminal restriction fragment length polymorphism. Dispersion indices and Mantel correlograms were used to test for the presence of spatial structure in the biofilm. Diversity metrics and rank-abundance distributions (RADs) were also generated. The study revealed spatial structure on a centimetre scale in eukaryotic microbes (fungi and algae), but not the bacteria. Fungal and bacterial communities were highly diverse; algal communities much less so. The RADs were characterized by a distinctive 'hollow' (concave up) profile and long tails of rare taxa. These findings have implications for understanding the ecology of epilithic biofilms and the spatial heterogeneity of stone biodeterioration.This work was supported by the Engineering and Physical Sciences Research Council (grant no. EP/G011338/1).This is the author accepted manuscript. The final version is available from OUP at http://femsec.oxfordjournals.org/content/91/3/fiu027

    Profiling microbial communities in manganese remediation systems treating coal mine drainage

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    Author Posting. © American Society for Microbiology, 2015. This article is posted here by permission of American Society for Microbiology for personal use, not for redistribution. The definitive version was published in Applied and Environmental Microbiology 81 (2015): 2189-2198, doi:10.1128/AEM.03643-14.Water discharging from abandoned coal mines can contain extremely high manganese levels. Removing this metal is an ongoing challenge. Passive Mn(II) removal beds (MRBs) contain microorganisms that oxidize soluble Mn(II) to insoluble Mn(III/IV) minerals, but system performance is unpredictable. Using amplicon pyrosequencing, we profiled the bacterial, fungal, algal and archaeal communities in four variably-performing MRBs in Pennsylvania to determine whether they differed among MRBs and from surrounding soil, and to establish the relative abundance of known Mn(II)-oxidizers. Archaea were not detected; PCRs with archaeal primers returned only non-target bacterial sequences. Fungal taxonomic profiles differed starkly between sites that remove the majority of influent Mn and those that do not, with the former dominated by Ascomycota (mostly Dothideomycetes) and the latter by Basidiomycota (almost entirely Agaricomycetes). Taxonomic profiles for the other groups did not differ significantly between MRBs, but OTU-based analyses showed significant clustering by MRB with all four groups (p<0.05). Soil samples clustered separately from MRBs in all groups except fungi, whose soil samples clustered loosely with their respective MRB. Known Mn(II) oxidizers accounted for a minor proportion of bacterial sequences (up to 0.20%) but a greater proportion of fungal sequences (up to 14.78%). MRB communities are more diverse than previously thought, and more organisms may be capable of Mn(II) oxidation than are currently known.This project was funded by Smithsonian Scholarly Studies and Next-Generation Sequencing grants to C.M.S., by a Smithsonian Postdoctoral Fellowship to D.L.C., and by the National Science Foundation, grant numbers EAR-1249489 (awarded to C.M.H.) and CBET-1336496 (awarded to C.M.H. and C.M.S.)

    Mechanisms of manganese(II) oxidation by filamentous ascomycete fungi vary with species and time as a function of secretome composition

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    © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Zeiner, C. A., Purvine, S. O., Zink, E., Wu, S., Pasa-Tolic, L., Chaput, D. L., Santelli, C. M., & Hansel, C. M. Mechanisms of manganese(II) oxidation by filamentous ascomycete fungi vary with species and time as a function of secretome composition. Frontiers in Microbiology, 12, (2021): 610497, https://doi.org/10.3389/fmicb.2021.610497.Manganese (Mn) oxides are among the strongest oxidants and sorbents in the environment, and Mn(II) oxidation to Mn(III/IV) (hydr)oxides includes both abiotic and microbially-mediated processes. While white-rot Basidiomycete fungi oxidize Mn(II) using laccases and manganese peroxidases in association with lignocellulose degradation, the mechanisms by which filamentous Ascomycete fungi oxidize Mn(II) and a physiological role for Mn(II) oxidation in these organisms remain poorly understood. Here we use a combination of chemical and in-gel assays and bulk mass spectrometry to demonstrate secretome-based Mn(II) oxidation in three phylogenetically diverse Ascomycetes that is mechanistically distinct from hyphal-associated Mn(II) oxidation on solid substrates. We show that Mn(II) oxidative capacity of these fungi is dictated by species-specific secreted enzymes and varies with secretome age, and we reveal the presence of both Cu-based and FAD-based Mn(II) oxidation mechanisms in all 3 species, demonstrating mechanistic redundancy. Specifically, we identify candidate Mn(II)-oxidizing enzymes as tyrosinase and glyoxal oxidase in Stagonospora sp. SRC1lsM3a, bilirubin oxidase in Stagonospora sp. and Paraconiothyrium sporulosum AP3s5-JAC2a, and GMC oxidoreductase in all 3 species, including Pyrenochaeta sp. DS3sAY3a. The diversity of the candidate Mn(II)-oxidizing enzymes identified in this study suggests that the ability of fungal secretomes to oxidize Mn(II) may be more widespread than previously thought.This work was supported by the National Science Foundation, grant numbers EAR-1249489 and CBET-1336496, both awarded to CH, by a JGI-EMSL Collaborative Science Initiative grant (proposal number 48100) awarded to CH and CS, and by the University of St. Thomas. Personal support for CZ was also provided by Harvard University and by a Ford Foundation Predoctoral Fellowship administered by the National Academies. A portion of this research was performed under the Facilities Integrating Collaborations for User Science (FICUS) program and used resources at the DOE Joint Genome Institute and the Environmental Molecular Sciences Laboratory (grid.436923.9), which are DOE Office of Science User Facilities. Both facilities are sponsored by the Biological and Environmental Research Program and operated under Contract Nos. DE-AC02-05CH11231 (JGI) and DE-AC05-76RL01830 (EMSL). Part of this research was performed at the Bauer Core Facility of the FAS Center for Systems Biology at Harvard University. A portion of the bioinformatics analysis was performed at Harvard’s FAS Research Computing facility

    Long-Term Recovery of Microbial Communities in the Boreal Bryosphere Following Fire Disturbance.

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    Our study used a ∼360-year fire chronosequence in northern Sweden to investigate post-fire microbial community dynamics in the boreal bryosphere (the living and dead parts of the feather moss layer on the forest floor, along with the associated biota). We anticipated systematic changes in microbial community structure and growth strategy with increasing time since fire (TSF) and used amplicon pyrosequencing to establish microbial community structure. We also recorded edaphic factors (relating to pH, C and N accumulation) and the physical characteristics of the feather moss layer. The molecular analyses revealed an unexpectedly diverse microbial community. The structure of the community could be largely explained by just two factors, TSF and pH, although the importance of TSF diminished as the forest recovered from disturbance. The microbial communities on the youngest site (TSF = 14 years) were clearly different from older locations (>100 years), suggesting relatively rapid post-fire recovery. A shift towards Proteobacterial taxa on older sites, coupled with a decline in the relative abundance of Acidobacteria, suggested an increase in resource availability with TSF. Saprotrophs dominated the fungal community. Mycorrhizal fungi appeared to decline in abundance with TSF, possibly due to changing N status. Our study provided evidence for the decadal-scale legacy of burning, with implications for boreal forests that are expected to experience more frequent burns over the course of the next century.Natural Environment Research Council (Grant ID: NE/ I027150/1), Royal Geographical Society (Grant ID: SRG 13:13), Trinity College Cambridg

    Profiling Microbial Communities in Manganese Remediation Systems Treating Coal Mine Drainage

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    To cope with different types of risks, farmers can implement on-farm strategies and risk-sharing strategies. Risk management tools within EU Common Agricultural Policy are subsidized crop insurance, mutual funds (MF), and income stabilization tool (IST). While subsidized crop insurance is widely applied, IST and MF are not so common. Price volatility and climate change risk significantly influence farm income. Mediterranean area is especially exposed to climate change, so Istria County as part of Mediterranean is chosen for research. IST could protect against income variability, but more research and discussions are needed prior to its commercial scale implementation. Qualitative research on the small sample was applied with the goal to explore attributes that could impact the selection of IST. Paper provides an overview of IST and previous experience of IST on the EU level, on the basis of semi structured interviews, explains the perception of climate risks and IST on wine cases in Istria. The results show that all selected cases were familiar with subsidized crop insurance; however, they were not familiar with IST. After being introduced to the IST, wine producers were ready to consider its application. Lack of experiences in business linkages could be a constraint in the development of IST and challenge for policymakers.razini gospodarstva i strategije za prijenos rizika. Strategije za upravljanje rizikom u okviru Zajedničke poljoprivredne politike EU dijele se na potporu za osiguranje prinosa, osiguranje dohotka i uzajamno osiguranje. Mjera potpora za osiguranje prinosa je široko primijenjena, dok su ostale dvije strategije u primjeni samo u nekim zemljama članicama. Promjenjivost cijena i neizvjesnost u proizvodnji zbog klimatskih promjena značajno utječu na dohodak poljoprivrednih gospodarstava. Područje Mediterana je posebno izloženo riziku klimatskih promjena, te je Istarska županija kao dio Mediterana izabrana za istraživanje. Osiguranje dohotka štiti od varijabilnosti dohotka, ali prije komercijalne primjene je potrebno provesti više istraživanja i rasprava. Kvalitativno istraživanje na malom uzorku primijenjeno je kako bi se ispitala obilježja koja mogu utjecati na izbor osiguranja dohotka. Rad daje pregled obilježja osiguranja dohotka i dosadašnja iskustva osiguranja dohotka na razini EU, primjenom polustrukturiranih intervjua, na izabranim vinogradarima Istre objašnjava percepciju o klimatskim rizicima i osiguranju dohotka. Rezultati pokazuju kako su svi ispitanici upoznati sa subvencioniranim osiguravanjem prinosa, ali nisu upoznati sa osiguranjem dohotka. Nakon što su ispitanici upoznati s osiguranjem dohotka sva su četiri proizvođača spremna razmotriti primjenu spomenute strategije. Manjak iskustva uzajamnog poslovanja može biti ograničenje razvoja osiguranja dohotka i izazov za donositelje političkih odluka

    Microbial Communities Promoting Mn(II) Oxidation in Ashumet Pond, a Historically Polluted Freshwater Pond Undergoing Remediation

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    <div><p>An extensive culture-dependent and -independent study was conducted to identify microorganisms contributing to the biogeochemical cycling of manganese (Mn) in Ashumet Pond, a freshwater pond in Massachusetts currently undergoing remediation. A variety of bacteria (including Gamma-, Beta-, and Alpha-proteobacteria, Firmicutes, and Bacteroides) and Ascoymete fungi were isolated from the pond that promote Mn(II) oxidation and subsequent formation of Mn(III/IV) oxide minerals. Targeted-amplicon pyrosequencing of the bacterial and fungal communities associated with Mn oxide-encrusted samples show a highly diverse microbial community, of which the cultured phylotypes represent a minor proportion. This suggests a larger community, not identified through culturing, contributes to Mn oxide formation within the Pond.</p></div
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