167 research outputs found

    Snapshot of the Eukaryotic Gene Expression in Muskoxen Rumen—A Metatranscriptomic Approach

    Get PDF
    BACKGROUND: Herbivores rely on digestive tract lignocellulolytic microorganisms, including bacteria, fungi and protozoa, to derive energy and carbon from plant cell wall polysaccharides. Culture independent metagenomic studies have been used to reveal the genetic content of the bacterial species within gut microbiomes. However, the nature of the genes encoded by eukaryotic protozoa and fungi within these environments has not been explored using metagenomic or metatranscriptomic approaches. METHODOLOGY/PRINCIPAL FINDINGS: In this study, a metatranscriptomic approach was used to investigate the functional diversity of the eukaryotic microorganisms within the rumen of muskoxen (Ovibos moschatus), with a focus on plant cell wall degrading enzymes. Polyadenylated RNA (mRNA) was sequenced on the Illumina Genome Analyzer II system and 2.8 gigabases of sequences were obtained and 59129 contigs assembled. Plant cell wall degrading enzyme modules including glycoside hydrolases, carbohydrate esterases and polysaccharide lyases were identified from over 2500 contigs. These included a number of glycoside hydrolase family 6 (GH6), GH48 and swollenin modules, which have rarely been described in previous gut metagenomic studies. CONCLUSIONS/SIGNIFICANCE: The muskoxen rumen metatranscriptome demonstrates a much higher percentage of cellulase enzyme discovery and an 8.7x higher rate of total carbohydrate active enzyme discovery per gigabase of sequence than previous rumen metagenomes. This study provides a snapshot of eukaryotic gene expression in the muskoxen rumen, and identifies a number of candidate genes coding for potentially valuable lignocellulolytic enzymes

    Healthcare providers’ perspectives of disrespect and abuse in maternity care facilities in Nigeria: a qualitative study

    Get PDF
    Objectives To explore healthcare providers’ perspectives of disrespect and abuse in maternity care and the impact on women’s health and well-being. Methods Qualitative interpretive approach using in-depth semi-structured interviews with sixteen healthcare providers in two public health facilities in Nigeria. Interviews were audio-recorded, transcribed, and analysed thematically. Results Healthcare providers’ accounts revealed awareness of what respectful maternity care encompassed in accordance with the existing guidelines. They considered disrespectful and abusive practices perpetrated or witnessed as violation of human rights, while highlighting women’s expectations of care as the basis for subjectivity of experiences. They perceived some practices as well-intended to ensure safety of mother and baby. Views reflected underlying gender-related notions and societal perceptions of women being considered weaker than men. There was recognition about adverse effects of disrespect and abuse including its impact on women, babies, and providers’ job satisfaction. Conclusions Healthcare providers need training on how to incorporate elements of respectful maternity care into practice including skills for rapport building and counselling. Women and family members should be educated about right to respectful care empowering them to report disrespectful practices

    Chronic Exposure of Corals to Fine Sediments: Lethal and Sub-Lethal Impacts

    Get PDF
    Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS) for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata) more than the upright branching species (Acropora millepora). The lowest sediment treatments that caused full colony mortality were 30 mg l−1 TSS (25 mg cm−2 day−1) for M. aequituberculata and 100 mg l−1 TSS (83 mg cm−2 day−1) for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue

    A Proposed Taxonomy of Anaerobic Fungi (Class Neocallimastigomycetes) Suitable for Large-Scale Sequence-Based Community Structure Analysis

    Get PDF
    Anaerobic fungi are key players in the breakdown of fibrous plant material in the rumen, but not much is known about the composition and stability of fungal communities in ruminants. We analyzed anaerobic fungi in 53 rumen samples from farmed sheep (4 different flocks), cattle, and deer feeding on a variety of diets. Denaturing gradient gel electrophoresis fingerprinting of the internal transcribed spacer 1 (ITS1) region of the rrn operon revealed a high diversity of anaerobic fungal phylotypes across all samples. Clone libraries of the ITS1 region were constructed from DNA from 11 rumen samples that had distinctly different fungal communities. A total of 417 new sequences were generated to expand the number and diversity of ITS1 sequences available. Major phylogenetic groups of anaerobic fungi in New Zealand ruminants belonged to the genera Piromyces, Neocallimastix, Caecomyces and Orpinomyces. In addition, sequences forming four novel clades were obtained, which may represent so far undetected genera or species of anaerobic fungi. We propose a revised phylogeny and pragmatic taxonomy for anaerobic fungi, which was tested and proved suitable for analysis of datasets stemming from high-throughput next-generation sequencing methods. Comparing our revised taxonomy to the taxonomic assignment of sequences deposited in the GenBank database, we believe that >29% of ITS1 sequences derived from anaerobic fungal isolates or clones are misnamed at the genus level

    Impacts of Sediments on Coral Energetics: Partitioning the Effects of Turbidity and Settling Particles

    Get PDF
    Sediment loads have long been known to be deleterious to corals, but the effects of turbidity and settling particles have not previously been partitioned. This study provides a novel approach using inert silicon carbide powder to partition and quantify the mechanical effects of sediment settling versus reduced light under a chronically high sedimentary regime on two turbid water corals commonly found in Singapore (Galaxea fascicularis and Goniopora somaliensis). Coral fragmentswere evenly distributed among three treatments: an open control (30% ambient PAR), a shaded control (15% ambient PAR) and sediment treatment (15% ambient PAR; 26.4 mg cm22 day21). The rate of photosynthesis and respiration, and the dark-adapted quantum yield were measured once a week for four weeks. By week four, the photosynthesis to respiration ratio (P/R ratio) and the photosynthetic yield (Fv/Fm) had fallen by 14% and 3–17% respectively in the shaded control,contrasting with corals exposed to sediments whose P/R ratio and yield had declined by 21% and 18–34% respectively. The differences in rates between the shaded control and the sediment treatment were attributed to the mechanical effects of sediment deposition. The physiological response to sediment stress differed between species with G. fascicularis experiencing a greater decline in the net photosynthetic yield (13%) than G. somaliensis (9.5%), but a smaller increase in the respiration rates (G. fascicularis = 9.9%, G. somaliensis = 14.2%). These different physiological responses were attributed, in part, to coral morphology and highlighted key physiological processes that drive species distribution along high to low turbidity and depositional gradients

    Women’s experiences of disrespect and abuse in maternity care facilities in Benue State, Nigeria

    Get PDF
    Background Disrespect and abuse (D&A) of women in health facilities continues to be a prevailing public health issue in many countries. Studies have reported significantly high prevalence of D&A among women during pregnancy and childbirth in Nigeria, but little is known about women’s perceptions and experiences of D&A during maternity care in the country. The aim of this study was to explore: 1) how women perceived their experiences of D&A during pregnancy, childbirth, and in the postnatal period in Benue State, Nigeria; and 2) how women viewed the impact of D&A on the future use of health facilities for maternity care. Method Five focus group discussions with a sample of 32 women were conducted as part of a qualitative phenomenological study. All the women received maternity care in health facilities in Benue State, Nigeria and had experienced at least one incident of disrespect and abuse. Audio-recorded discussions were transcribed and analysed using a six-stage thematic analysis using NVivo11. Results The participants perceived incidents such as being shouted at and the use of abusive language as a common practice. Women described these incidents as devaluing and dehumanising to their sense of dignity. Some women perceived that professionals did not intend to cause harm by such behaviours. Emerged themes included: (1) ‘normative’ practice; (2) dehumanisation of women; (3) 'no harm intended' and (4) intentions about the use of maternity services in future. The women highlighted the importance of accessing health facilities for safe childbirth and expressed that the experiences of D&A may not impact their intended use of health facilities. However, the accounts reflected their perceptions about the inherent lack of choice and an underlying sense of helplessness. Conclusion Incidents of D&A that were perceived as commonplace carry substantial implications for the provision of respectful maternity care in Nigeria and other similar settings. As a country with one of the highest rates of maternal deaths, the findings point to the need for policy and practice to address the issue urgently through implementing preventive measures, including empowering women to reinforce their right to be treated with dignity and respect, and sensitising health care professionals

    Genome of the anaerobic fungus Orpinomyces sp. strain C1A reveals the unique evolutionary history of a remarkable plant biomass degrader

    Get PDF
    Anaerobic gut fungi represent a distinct early-branching fungal phylum (Neocallimastigomycota) and reside in the rumen, hindgut, and feces of ruminant and nonruminant herbivores. The genome of an anaerobic fungal isolate, Orpinomyces sp. strain C1A, was sequenced using a combination of Illumina and PacBio single-molecule real-time (SMRT) technologies. The large genome (100.95 Mb, 16,347 genes) displayed extremely low G+C content (17.0%), large noncoding intergenic regions (73.1%), proliferation of microsatellite repeats (4.9%), and multiple gene duplications. Comparative genomic analysis identified multiple genes and pathways that are absent in Dikarya genomes but present in early-branching fungal lineages and/or nonfungal Opisthokonta. These included genes for posttranslational fucosylation, the production of specific intramembrane proteases and extracellular protease inhibitors, the formation of a complete axoneme and intraflagellar trafficking machinery, and a near-complete focal adhesion machinery. Analysis of the lignocellulolytic machinery in the C1A genome revealed an extremely rich repertoire, with evidence of horizontal gene acquisition from multiple bacterial lineages. Experimental analysis indicated that strain C1A is a remarkable biomass degrader, capable of simultaneous saccharification and fermentation of the cellulosic and hemicellulosic fractions in multiple untreated grasses and crop residues examined, with the process significantly enhanced by mild pretreatments. This capability, acquired during its separate evolutionary trajectory in the rumen, along with its resilience and invasiveness compared to prokaryotic anaerobes, renders anaerobic fungi promising agents for consolidated bioprocessing schemes in biofuels production.Peer reviewedMicrobiology and Molecular GeneticsBiosystems and Agricultural Engineerin
    corecore