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There has been a void in the discovery and development of new antibiotic classes over the past four decades due, in part, to the traditional bioprospecting pipeline becoming inefficient from high compound rediscovery rates and high costs. The need for new antibiotic classes is urgent as antimicrobial drug resistant infections are now a major public health concern. Strategies such as exploring novel environments, use of next-generation sequencing, and metagenomics may reduce rediscovery rates and costs which could help accelerate lead discovery and encourage greater participation in bioprospecting. Whole genome-sequencing and analysis was used to characterise four bacterial strains (Y1-4) isolated from raw honey that were shown to have antibiotic activity. The isolates were identified as Bacillus and were closely related but distinctive strains with variations amongst their secondary metabolite profiles. All isolates contained a gene cluster homologous to AS- 48, a circular bacteriocin produced by Enterococcus faecalis, which has broad-spectrum antibiotic activity. To date, no example of this bacteriocin has been reported in Bacillus. This work demonstrated the value of whole-microbial genome sequencing for dereplication. A pipeline for the low-cost sequencing and assembly of bacterial genomes using Oxford Nanopore MinION was developed in order to produce contiguous and accurate genome assemblies for taxonomic and bioprospecting analysis. The pipeline developed used a combination of Nanopore draft assembly by Canu and polishing with RACON and Nanopolish, with final polishing with Illumina reads using Pilon. The Nanopore-only assembly of Streptomyces coelicolor A3(2) produced was contiguous and covered 98.9 % of reference. AntiSMASH analysis identified the full secondary metabolite profile of the genome through homology searches. However, indel rates were high (66.82 per 100 kbp) causing fragmented gene annotations which limited secondary metabolite structure prediction. Illumina read polishing reduced indels (2.03 per 100 kbp) and enabled accurate structure prediction from the identified biosynthetic pathways. This demonstrates that Nanopore sequencing can provide a viable dereplication strategy by detection of known biosynthetic pathways. Additionally, supplementation with Illumina sequencing can allow for structure prediction of biosynthetic pathways which could inform chemical extraction strategies for novel pathways. Nanopore sequencing was further utilised to characterise an antibiotic producing isolate (KB16) active against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus from the hot spring of the Roman Baths, UK. Genomic analysis showed KB16 to be highly related to Streptomyces canus and to contain 26 putative secondary metabolite gene clusters - some of which were potentially novel. One of the gene clusters was identified as encoding the antibiotic albaflavenone. Attempts to chemically identify the antibiotic produced by KB16 showed that it may produce multiple antimicrobial compounds. These findings demonstrate the value in prospecting underexplored environments such as the Roman Baths for microbially-derived antimicrobial leads. A PCR screen was used to amplify NRPS and PKS gene fragments from a human oral metagenome. Analysis of the fragments suggested that some are from uncharacterised gene clusters. Nanopore shotgun metagenomic sequencing was used to profile the water of the Roman Baths which revealed a diverse microbiome of species with reported metabolic characteristics that are in keeping with the known geochemistry of the waters and aligned with 16S rRNA analysis. Further analysis also identified putative heavy metal resistance genes which can be a co-marker for their metabolism and aligned with the chemical properties of the water. These findings demonstrate the potential value in these sites for bioprospecting whilst also giving insight that can inform bioprospecting strategies. The investigations also highlight the utility of Nanopore sequencing for taxonomic and functional gene profiling of environmental microbiomes. In combination these findings have all contributed information on novel environments, potential isolate leads, and cost-efficient methodologies to accelerate the discovery of microbially-derived antibiotics.

This study used a sequential, primarily explanatory, mixed methods analysis to investigate the relationships between Psychological Inflexibility (the central concept of Acceptance and Commitment Therapy, ‘ACT’), Early Maladaptive Schemas (a key concept of Schema Therapy) and Burnout, and how these factors might inform appropriate interventions. The first component of this study used an online survey combining the Maslach Burnout Inventory–General Survey (MBI-GS, Maslach et al., 1996), the AAQ-ii (Acceptance and Action Questionnaire, Bond et al., 2011) and the Young Schema Questionnaire (YSQ-S3, Young, 2005), along with additional demographic items. A total of 506 participants completed the survey. Quantitative results demonstrated significant relationships between Psychological Inflexibility, a number of Early Maladaptive Schemas, specific demographic variables, and Burnout. Based on these relationships, a number of regression models were created to explain variance in the three dimensions of Burnout measured (Emotional Exhaustion, Cynicism and Professional Efficacy). Additionally principal components (‘factor’) analysis was used to create a single burnout factor, used in additional regression-modelling. The second component of this study used thematic analysis to analyse data collected from interviews with six therapists experienced in working with symptoms of burnout, three identifying themselves as ACT Therapists and three as Schema Therapists. The analysis of the ACT Therapist data resulted in four superordinate themes: 1) Key ACT Concepts and Burnout, 2) Clinical Observations, 3) Assessment and Intervention Principles, and 4) Intervention Specifics. The analysis of the Schema Therapist data also resulted in four superordinate themes: 1) Coping styles, 2) Schema Modes, 3) Understanding Burnout - The Clinician’s Perspective, and 4) Formulation and Intervention. The results from both components are discussed in the context of published literature, relevance to counselling psychology, potential interventions and opportunities for future research.