CARD 2023: expanded curation, support for machine learning, and resistome prediction at the Comprehensive Antibiotic Resistance Database.

The Comprehensive Antibiotic Resistance Database (CARD; card.mcmaster.ca) combines the Antibiotic Resistance Ontology (ARO) with curated AMR gene (ARG) sequences and resistance-conferring mutations to provide an informatics framework for annotation and interpretation of resistomes. As of version 3.2.4, CARD encompasses 6627 ontology terms, 5010 reference sequences, 1933 mutations, 3004 publications, and 5057 AMR detection models that can be used by the accompanying Resistance Gene Identifier (RGI) software to annotate genomic or metagenomic sequences. Focused curation enhancements since 2020 include expanded ß-lactamase curation, incorporation of likelihood-based AMR mutations for Mycobacterium tuberculosis, addition of disinfectants and antiseptics plus their associated ARGs, and systematic curation of resistance-modifying agents. This expanded curation includes 180 new AMR gene families, 15 new drug classes, 1 new resistance mechanism, and two new ontological relationships: evolutionary_variant_of and is_small_molecule_inhibitor. In silico prediction of resistomes and prevalence statistics of ARGs has been expanded to 377 pathogens, 21,079 chromosomes, 2,662 genomic islands, 41,828 plasmids and 155,606 whole-genome shotgun assemblies, resulting in collation of 322,710 unique ARG allele sequences. New features include the CARD:Live collection of community submitted isolate resistome data and the introduction of standardized 15 character CARD Short Names for ARGs to support machine learning efforts.

CARD 2020: antibiotic resistome surveillance with the comprehensive antibiotic resistance database.

The Comprehensive Antibiotic Resistance Database (CARD; https://card.mcmaster.ca) is a curated resource providing reference DNA and protein sequences, detection models and bioinformatics tools on the molecular basis of bacterial antimicrobial resistance (AMR). CARD focuses on providing high-quality reference data and molecular sequences within a controlled vocabulary, the Antibiotic Resistance Ontology (ARO), designed by the CARD biocuration team to integrate with software development efforts for resistome analysis and prediction, such as CARD's Resistance Gene Identifier (RGI) software. Since 2017, CARD has expanded through extensive curation of reference sequences, revision of the ontological structure, curation of over 500 new AMR detection models, development of a new classification paradigm and expansion of analytical tools. Most notably, a new Resistomes & Variants module provides analysis and statistical summary of in silico predicted resistance variants from 82 pathogens and over 100 000 genomes. By adding these resistance variants to CARD, we are able to summarize predicted resistance using the information included in CARD, identify trends in AMR mobility and determine previously undescribed and novel resistance variants. Here, we describe updates and recent expansions to CARD and its biocuration process, including new resources for community biocuration of AMR molecular reference data.

Early childhood development practices in a remote Aboriginal Community Controlled Health Services setting.

OBJECTIVE: Supporting Early Childhood Development (ECD) is an Australian national priority. Aboriginal children in Western Australia's Kimberley region have much higher rates of developmental concerns at school entry than non-Aboriginal children. We aimed to describe ECD practices in the participating service; document follow-up of identified developmental concerns; and identify barriers and enablers to incorporating ECD practices into clinic activity. DESIGN: Mixed-method design incorporating clinical audit and staff interviews. SETTING: An Aboriginal Community Controlled Health Service (ACCHS) in the Kimberley region. PARTICIPANTS: A total of 176 children receiving primary health care through the participating ACCHS; interviews with five ACCHS staff members. MAIN OUTCOME MEASURES: Frequency of developmental enquiry by age and domain; follow-up of identified developmental concerns; and barriers and enablers to ECD practices. RESULTS: Developmental enquiry was documented for 114 of 176 eligible children (65%), including in 80% of ACCHS child health assessments. Standardised ECD assessments were less common. Staff were aware of the importance of developmental enquiry, however, barriers to increasing ECD practices included a lack of resources and structured staff education, time pressures and a lack of role clarity between the ACCHS and government community health clinic. CONCLUSIONS: This study provides insight into ECD practices in an ACCHS setting, highlighting the potential of primary health care to have an enhanced role in ECD if appropriate systems, training and tools are provided. A lack of role clarity across services, combined with poor communication between services, creates a potential risk for missed opportunities to support ECD.

Acute kidney injury in Indigenous Australians in the Kimberley: age distribution and associated diagnoses.

OBJECTIVE: To describe the frequencies of acute kidney injury (AKI) and of associated diagnoses in Indigenous people in a remote Western Australian region. DESIGN: Retrospective population-based study of AKI events confirmed by changes in serum creatinine levels. SETTING, PARTICIPANTS: Aboriginal and Torres Strait Islander residents of the Kimberley region of Western Australia, aged 15 years or more and without end-stage kidney disease, for whom AKI between 1 June 2009 and 30 May 2016 was confirmed by an acute rise in serum creatinine levels. MAIN OUTCOME MEASURES: Age-specific AKI rates; principal and other diagnoses. RESULTS: 324 AKI events in 260 individuals were recorded; the median age of patients was 51.8 years (IQR, 43.9-61.0 years), and 176 events (54%) were in men. The overall AKI rate was 323 events (95% CI, 281-367) per 100 000 population; 92 events (28%) were in people aged 15-44 years. 52% of principal diagnoses were infectious in nature, including pneumonia (12% of events), infections of the skin and subcutaneous tissue (10%), and urinary tract infections (7.7%). 80 events (34%) were detected on or before the date of admission; fewer than one-third of discharge summaries (61 events, 28%) listed AKI as a primary or other diagnosis. CONCLUSION: The age distribution of AKI events among Indigenous Australians in the Kimberley was skewed to younger groups than in the national data on AKI. Infectious conditions were common in patients, underscoring the significance of environmental determinants of health. Primary care services can play an important role in preventing community-acquired AKI; applying pathology-based criteria could improve the detection of AKI.

Pregnancy intentions in a group of remote-dwelling Australian Aboriginal women: a qualitative exploration of formation, expression and implications for clinical practice.

BACKGROUND: Unintended pregnancies are associated with poorer obstetric outcomes and are sometimes measured at a population level as a surrogate marker for reproductive autonomy and access to health services, including contraception. Aboriginal Australians face many disparities in health outcomes, including in reproductive health and antenatal care. We aimed to explore the formation and expression of pregnancy intentions in an Aboriginal population to inform health service improvements. METHODS: Semi-structured interviews were conducted with 27 remote-dwelling Aboriginal women, aged 18-49 years. Content analysis was conducted; key themes were discussed with groups of women from participating communities to refine interpretation. RESULTS: Most (19/27) participants expressed pregnancy intentions congruent with reported contraceptive behaviour while eight expressed ambivalent or uncertain intentions. Intentions were shaped by traditional kinship practices, reproductive autonomy and desired family formation. Younger women tended to aspire to smaller family sizes than older women and support was expressed for the postponement of first pregnancy to achieve other life goals. Women in these communities hold strong traditional beliefs, including regarding conception, but did not use traditional methods of contraception in place of modern methods. Reproductive coercion, in the form of pressure to fall pregnant, was recognised as an important issue by women in the community. CONCLUSION: Consultation strategies that promote rapport, allow space for uncertainty and are inclusive of important personal and cultural contexts are likely to improve shared understanding of pregnancy intention. Universal screening for reproductive coercion and broad counselling on contraceptive options (including discrete methods) may reduce unmet need for contraception. Community approaches supporting reproductive autonomy that is inclusive of men, and enhanced educational and occupational opportunities for young women are needed.

Enhanced annotations and features for comparing thousands of Pseudomonas genomes in the Pseudomonas genome database.

The Pseudomonas Genome Database (http://www.pseudomonas.com) is well known for the application of community-based annotation approaches for producing a high-quality Pseudomonas aeruginosa PAO1 genome annotation, and facilitating whole-genome comparative analyses with other Pseudomonas strains. To aid analysis of potentially thousands of complete and draft genome assemblies, this database and analysis platform was upgraded to integrate curated genome annotations and isolate metadata with enhanced tools for larger scale comparative analysis and visualization. Manually curated gene annotations are supplemented with improved computational analyses that help identify putative drug targets and vaccine candidates or assist with evolutionary studies by identifying orthologs, pathogen-associated genes and genomic islands. The database schema has been updated to integrate isolate metadata that will facilitate more powerful analysis of genomes across datasets in the future. We continue to place an emphasis on providing high-quality updates to gene annotations through regular review of the scientific literature and using community-based approaches including a major new Pseudomonas community initiative for the assignment of high-quality gene ontology terms to genes. As we further expand from thousands of genomes, we plan to provide enhancements that will aid data visualization and analysis arising from whole-genome comparative studies including more pan-genome and population-based approaches.

Uptake of long-acting, reversible contraception in three remote Aboriginal communities: a population-based study.

OBJECTIVE: To assess the use, effectiveness and acceptance of prescribed contraception in three remote Western Australian Aboriginal communities. PARTICIPANTS AND DESIGN: Mixed method study, including retrospective file review of contraception methods for 566 regular female Aboriginal patients, 1 November 2010 - 1 September 2014, and semi-structured interviews with 20 Aboriginal women. SETTING: Primary care clinics in three remote Aboriginal communities. MAIN OUTCOME MEASURES: Number of episodes of contraceptive use, effectiveness and continuation rates of prescribed contraceptive use; personal experiences, attitudes towards and beliefs about contraception options. RESULTS: 34% of women had used contraception, ranging from 15% of women aged younger than 15 years to 55% of women aged 15-19 years. The most common forms of contraception at the census date were long-acting reversible contraceptives (LARCs): 77% of women using contraception had an etonogestrel implant and 7% had depot medroxyprogesterone. Etonogestrel continuation rates at 1, 2 and 3 years were 87% (95% CI, 81-92%), 72% (95% CI, 64-78%) and 51% (95% CI, 41-60%) respectively. Medroxyprogesterone depot continuation at one year was only 14% (95% CI, 8-22%). Social acceptance of the etonogestrel implant was high; no concerns were raised about stigma or unwanted attention related to implant use. CONCLUSION: The high uptake of LARCs in these communities is consistent with international recommendations about contraception use. High acceptability was reflected in excellent continuation rates. Service delivery models that use community engagement and capacity building are recommended for broadening the focus of sexual health beyond sexually transmitted disease detection and management, giving priority to the reproductive rights and unmet needs of Aboriginal women.

A phylogenomic and molecular markers based analysis of the phylum Chlamydiae: proposal to divide the class Chlamydiia into two orders, Chlamydiales and Parachlamydiales ord. nov., and emended description of the class Chlamydiia.

The phylum Chlamydiae contains nine ecologically and genetically diverse families all placed within a single order. In this work, we have completed a comprehensive comparative analysis of 36 sequenced Chlamydiae genomes in order to identify shared molecular characteristics, namely conserved signature insertions/deletions (CSIs) and conserved signature proteins (CSPs), which can serve as distinguishing characteristics of supra-familial clusters within the phylum Chlamydiae. Our analysis has led to the identification of 32 CSIs which are specific to clusters within the phylum Chlamydiae at various phylogenetic depths. Importantly, 17 CSIs and 98 CSPs were found to be specific for the family Chlamydiaceae while another 3 CSI variants and 15 CSPs were specific for a grouping of the families Criblamydiaceae, Parachlamydiaceae, Simkaniaceae and Waddliaceae. These two clusters were also found to be distinguishable in 16S rRNA based phylogenetic trees, concatenated protein based phylogenetic trees, character compatibility based phylogenetic analyses, and on the basis of 16S rRNA gene sequence identity and average amino acid identity values. On the basis of the identified molecular characteristics, branching in phylogenetic trees, and the genetic distance between the two clusters within the phylum Chlamydiae we propose a division of the class Chlamydiia into two orders: an emended order Chlamydiales, containing the family Chlamydiaceae and the closely related Candidatus family Clavichlamydiaceae, and the novel order Parachlamydiales ord. nov. containing the families Parachlamydiaceae, Simkaniaceae and Waddliaceae and the Candidatus families Criblamydiaceae, Parilichlamydiaceae, Piscichlamydiaceae, and Rhabdochlamydiaceae. We also include a brief discussion of the reunification of the genera Chlamydia and Chlamydophila.

Hepatitis B notifications in a vaccinated cohort of Aboriginal people in the Kimberley region.

OBJECTIVES: To identify cases of hepatitis B infection after vaccination in Kimberley residents and determine maternal serostatus as a potential indicator of mode of transmission. DESIGN AND PARTICIPANTS: Retrospective review of Kimberley residents with notified hepatitis B infection using records of vaccination history and child and maternal serology. MAIN OUTCOME MEASURES: Confirmed cases of hepatitis B infection after vaccination; chronic infection in cases of hepatitis B infection after vaccination; maternal serostatus in confirmed cases of hepatitis B infection after vaccination. RESULTS: From 1 January 1984 to 31 March 2011, we identified 17 cases of Aboriginal residents with hepatitis B infection after vaccination (10 chronic infections, five not defined and two cleared). In six patients, maternal chronic infection had been identified at some stage, raising the possibility of vertical transmission. In seven patients, maternal serology or evidence of subsequent acquisition suggested that horizontal transmission and therefore vaccination failure was likely. For four patients, there was inadequate information to assess possible mode of transmission. CONCLUSIONS: Hepatitis B infection after full vaccination is not limited to children of mothers with active infection. Further undiagnosed infections in the Kimberley are likely, and active monitoring to detect the extent and likely cause of hepatitis B infection in vaccinated children is needed. In children where vertical transmission is a risk, prospective follow-up is warranted.

A comparison of brain retraction mechanisms using finite element analysis and the effects of regionally heterogeneous material properties.

Finite element (FE) simulations of the brain undergoing neurosurgical procedures present us with the great opportunity to better investigate, understand, and optimize surgical techniques and equipment. FE models provide access to data such as the stress levels within the brain that would otherwise be inaccessible with the current medical technology. Brain retraction is often a dangerous but necessary part of neurosurgery, and current research focuses on minimizing trauma during the procedure. In this work, we present a simulation-based comparison of different types of retraction mechanisms. We focus on traditional spatulas and tubular retractors. Our results show that tubular retractors result in lower average predicted stresses, especially in the subcortical structures and corpus callosum. Additionally, we show that changing the location of retraction can greatly affect the predicted stress results. As the model predictions highly depend on the material model and parameters used for simulations, we also investigate the importance of using region-specific hyperelastic and viscoelastic material parameters when modelling a three-dimensional human brain during retraction. Our investigations demonstrate how FE simulations in neurosurgical techniques can provide insight to surgeons and medical device manufacturers. They emphasize how further work into this direction could greatly improve the management and prevention of injury during surgery. Additionally, we show the importance of modelling the human brain with region-dependent parameters in order to provide useful predictions for neurosurgical procedures.

The PHA4GE Microbial Data-Sharing Accord: establishing baseline consensus microbial data-sharing norms to facilitate cross-sectoral collaboration.

Microbial data sharing underlies evidence-based microbial research, as well as pathogen surveillance and analysis essential to public health. While the need for data sharing was highlighted during the SARS-CoV-2 pandemic, some concerns regarding secondary data use have also surfaced. Although general guidelines are available for data sharing, we note the absence of a set of established, universal, unambiguous and accessible principles to guide the secondary use of microbial data. Here, we propose the Public Health Alliance for Genomic Epidemiology (PHA4GE) Microbial Data-Sharing Accord to consolidate consensus norms and accepted practices for the secondary use of microbial data. The Accord provides a set of seven simple, baseline principles to address key concerns that may arise for researchers providing microbial datasets for secondary use and to guide responsible use by data users. By providing clear rules for secondary use of microbial data, the Accord can increase confidence in sharing by data providers and protect against data mis-use during secondary analyses.

AMRColab - a user-friendly antimicrobial resistance detection and visualization tool.

Antimicrobial resistance (AMR) poses a significant threat to global public health, with the potential to cause millions of deaths annually by 2050. Effective surveillance of AMR pathogens is crucial for monitoring and predicting their behaviour in response to antibiotics. However, many public health professionals lack the necessary bioinformatics skills and resources to analyse pathogen genomes effectively. To address this challenge, we developed AMRColab, an open-access bioinformatics analysis suite hosted on Google Colaboratory. AMRColab enables users with limited or no bioinformatics training to detect and visualize AMR determinants in pathogen genomes using a 'plug-and-play' approach. The platform integrates established bioinformatics tools such as AMRFinderPlus and hAMRonization, allowing users to analyse, compare and visualize trends in AMR pathogens easily. A trial run using methicillin-resistant Staphylococcus aureus (MRSA) strains demonstrated AMRColab's effectiveness in identifying AMR determinants and facilitating comparative analysis across strains. A workshop was conducted and feedback from participants indicated high confidence in using AMRColab and a willingness to incorporate it into their research. AMRColab's user-friendly interface and modular design make it accessible to a diverse audience, including medical laboratory technologists, medical doctors and public health scientists, regardless of their bioinformatics expertise. Future improvements to AMRColab will include enhanced visualization tools, multilingual support and the establishment of an online community platform. AMRColab represents a significant step towards democratizing AMR surveillance and empowering public health professionals to combat AMR effectively.

Mef2d potentiates type-2 immune responses and allergic lung inflammation.

Innate lymphoid cells (ILCs) and adaptive T lymphocytes promote tissue homeostasis and protective immune responses. Their production depends on the transcription factor GATA3, which is further elevated specifically in ILC2s and T helper 2 cells to drive type-2 immunity during tissue repair, allergic disorders, and anti-helminth immunity. The control of this crucial up-regulation is poorly understood. Using CRISPR screens in ILCs we identified previously unappreciated myocyte-specific enhancer factor 2d (Mef2d)-mediated regulation of GATA3-dependent type-2 lymphocyte differentiation. Mef2d-deletion from ILC2s and/or T cells specifically protected against an allergen lung challenge. Mef2d repressed Regnase-1 endonuclease expression to enhance IL-33 receptor production and IL-33 signaling and acted downstream of calcium-mediated signaling to translocate NFAT1 to the nucleus to promote type-2 cytokine-mediated immunity.

PHA4GE quality control contextual data tags: standardized annotations for sharing public health sequence datasets with known quality issues to facilitate testing and training.

As public health laboratories expand their genomic sequencing and bioinformatics capacity for the surveillance of different pathogens, labs must carry out robust validation, training, and optimization of wet- and dry-lab procedures. Achieving these goals for algorithms, pipelines and instruments often requires that lower quality datasets be made available for analysis and comparison alongside those of higher quality. This range of data quality in reference sets can complicate the sharing of sub-optimal datasets that are vital for the community and for the reproducibility of assays. Sharing of useful, but sub-optimal datasets requires careful annotation and documentation of known issues to enable appropriate interpretation, avoid being mistaken for better quality information, and for these data (and their derivatives) to be easily identifiable in repositories. Unfortunately, there are currently no standardized attributes or mechanisms for tagging poor-quality datasets, or datasets generated for a specific purpose, to maximize their utility, searchability, accessibility and reuse. The Public Health Alliance for Genomic Epidemiology (PHA4GE) is an international community of scientists from public health, industry and academia focused on improving the reproducibility, interoperability, portability, and openness of public health bioinformatic software, skills, tools and data. To address the challenges of sharing lower quality datasets, PHA4GE has developed a set of standardized contextual data tags, namely fields and terms, that can be included in public repository submissions as a means of flagging pathogen sequence data with known quality issues, increasing their discoverability. The contextual data tags were developed through consultations with the community including input from the International Nucleotide Sequence Data Collaboration (INSDC), and have been standardized using ontologies - community-based resources for defining the tag properties and the relationships between them. The standardized tags are agnostic to the organism and the sequencing technique used and thus can be applied to data generated from any pathogen using an array of sequencing techniques. The tags can also be applied to synthetic (lab created) data. The list of standardized tags is maintained by PHA4GE and can be found at https://github.com/pha4ge/contextual_data_QC_tags. Definitions, ontology IDs, examples of use, as well as a JSON representation, are provided. The PHA4GE QC tags were tested, and are now implemented, by the FDA's GenomeTrakr laboratory network as part of its routine submission process for SARS-CoV-2 wastewater surveillance. We hope that these simple, standardized tags will help improve communication regarding quality control in public repositories, in addition to making datasets of variable quality more easily identifiable. Suggestions for additional tags can be submitted to PHA4GE via the New Term Request Form in the GitHub repository. By providing a mechanism for feedback and suggestions, we also expect that the tags will evolve with the needs of the community.

The Canadian VirusSeq Data Portal & Duotang: open resources for SARS-CoV-2 viral sequences and genomic epidemiology.

The COVID-19 pandemic led to a large global effort to sequence SARS-CoV-2 genomes from patient samples to track viral evolution and inform public health response. Millions of SARS-CoV-2 genome sequences have been deposited in global public repositories. The Canadian COVID-19 Genomics Network (CanCOGeN - VirusSeq), a consortium tasked with coordinating expanded sequencing of SARS-CoV-2 genomes across Canada early in the pandemic, created the Canadian VirusSeq Data Portal, with associated data pipelines and procedures, to support these efforts. The goal of VirusSeq was to allow open access to Canadian SARS-CoV-2 genomic sequences and enhanced, standardized contextual data that were unavailable in other repositories and that meet FAIR standards (Findable, Accessible, Interoperable and Reusable). In addition, the Portal data submission pipeline contains data quality checking procedures and appropriate acknowledgement of data generators that encourages collaboration. From inception to execution, the portal was developed with a conscientious focus on strong data governance principles and practices. Extensive efforts ensured a commitment to Canadian privacy laws, data security standards, and organizational processes. This Portal has been coupled with other resources like Viral AI and was further leveraged by the Coronavirus Variants Rapid Response Network (CoVaRR-Net) to produce a suite of continually updated analytical tools and notebooks. Here we highlight this Portal, including its contextual data not available elsewhere, and the 'Duotang', a web platform that presents key genomic epidemiology and modeling analyses on circulating and emerging SARS-CoV-2 variants in Canada. Duotang presents dynamic changes in variant composition of SARS-CoV-2 in Canada and by province, estimates variant growth, and displays complementary interactive visualizations, with a text overview of the current situation. The VirusSeq Data Portal and Duotang resources, alongside additional analyses and resources computed from the Portal (COVID-MVP, CoVizu), are all open-source and freely available. Together, they provide an updated picture of SARS-CoV-2 evolution to spur scientific discussions, inform public discourse, and support communication with and within public health authorities. They also serve as a framework for other jurisdictions interested in open, collaborative sequence data sharing and analyses.

The Canadian VirusSeq Data Portal and Duotang: open resources for SARS-CoV-2 viral sequences and genomic epidemiology.

The COVID-19 pandemic led to a large global effort to sequence SARS-CoV-2 genomes from patient samples to track viral evolution and inform the public health response. Millions of SARS-CoV-2 genome sequences have been deposited in global public repositories. The Canadian COVID-19 Genomics Network (CanCOGeN - VirusSeq), a consortium tasked with coordinating expanded sequencing of SARS-CoV-2 genomes across Canada early in the pandemic, created the Canadian VirusSeq Data Portal, with associated data pipelines and procedures, to support these efforts. The goal of VirusSeq was to allow open access to Canadian SARS-CoV-2 genomic sequences and enhanced, standardized contextual data that were unavailable in other repositories and that meet FAIR standards (Findable, Accessible, Interoperable and Reusable). In addition, the portal data submission pipeline contains data quality checking procedures and appropriate acknowledgement of data generators that encourages collaboration. From inception to execution, the portal was developed with a conscientious focus on strong data governance principles and practices. Extensive efforts ensured a commitment to Canadian privacy laws, data security standards, and organizational processes. This portal has been coupled with other resources, such as Viral AI, and was further leveraged by the Coronavirus Variants Rapid Response Network (CoVaRR-Net) to produce a suite of continually updated analytical tools and notebooks. Here we highlight this portal (https://virusseq-dataportal.ca/), including its contextual data not available elsewhere, and the Duotang (https://covarr-net.github.io/duotang/duotang.html), a web platform that presents key genomic epidemiology and modelling analyses on circulating and emerging SARS-CoV-2 variants in Canada. Duotang presents dynamic changes in variant composition of SARS-CoV-2 in Canada and by province, estimates variant growth, and displays complementary interactive visualizations, with a text overview of the current situation. The VirusSeq Data Portal and Duotang resources, alongside additional analyses and resources computed from the portal (COVID-MVP, CoVizu), are all open source and freely available. Together, they provide an updated picture of SARS-CoV-2 evolution to spur scientific discussions, inform public discourse, and support communication with and within public health authorities. They also serve as a framework for other jurisdictions interested in open, collaborative sequence data sharing and analyses.

A defect in ATP-citrate lyase links acetyl-CoA production, virulence factor elaboration and virulence in Cryptococcus neoformans.

The interaction of Cryptococcus neoformans with phagocytic cells of the innate immune system is a key step in disseminated disease leading to meningoencephalitis in immunocompromised individuals. Transcriptional profiling of cryptococcal cells harvested from cell culture medium or from macrophages found differential expression of metabolic and other functions during fungal adaptation to the intracellular environment. We focused on the ACL1 gene for ATP-citrate lyase, which converts citrate to acetyl-CoA, because this gene showed elevated transcript levels in macrophages and because of the importance of acetyl-CoA as a central metabolite. Mutants lacking ACL1 showed delayed growth on medium containing glucose, reduced cellular levels of acetyl-CoA, defective production of virulence factors, increased susceptibility to the antifungal drug fluconazole and decreased survival within macrophages. Importantly, acl1 mutants were unable to cause disease in a murine inhalation model, a phenotype that was more extreme than other mutants with defects in acetyl-CoA production (e.g. an acetyl-CoA synthetase mutant). Loss of virulence is likely due to perturbation of critical physiological interconnections between virulence factor expression and metabolism in C. neoformans. Phylogenetic analysis and structural modelling of cryptococcal Acl1 identified three indels unique to fungal protein sequences; these differences may provide opportunities for the development of pathogen-specific inhibitors.

Adaptation of Cryptococcus neoformans to mammalian hosts: integrated regulation of metabolism and virulence.

The basidiomycete fungus Cryptococcus neoformans infects humans via inhalation of desiccated yeast cells or spores from the environment. In the absence of effective immune containment, the initial pulmonary infection often spreads to the central nervous system to result in meningoencephalitis. The fungus must therefore make the transition from the environment to different mammalian niches that include the intracellular locale of phagocytic cells and extracellular sites in the lung, bloodstream, and central nervous system. Recent studies provide insights into mechanisms of adaptation during this transition that include the expression of antiphagocytic functions, the remodeling of central carbon metabolism, the expression of specific nutrient acquisition systems, and the response to hypoxia. Specific transcription factors regulate these functions as well as the expression of one or more of the major known virulence factors of C. neoformans. Therefore, virulence factor expression is to a large extent embedded in the regulation of a variety of functions needed for growth in mammalian hosts. In this regard, the complex integration of these processes is reminiscent of the master regulators of virulence in bacterial pathogens.

A Schema for Digitized Surface Swab Site Metadata in Open-Source DNA Sequence Databases.

Large, open-source DNA sequence databases have been generated, in part, through the collection of microbial pathogens by swabbing surfaces in built environments. Analyzing these data in aggregate through public health surveillance requires digitization of the complex, domain-specific metadata that are associated with the swab site locations. However, the swab site location information is currently collected in a single, free-text, "isolation source", field-promoting generation of poorly detailed descriptions with various word order, granularity, and linguistic errors, making automation difficult and reducing machine-actionability. We assessed 1,498 free-text swab site descriptions that were generated during routine foodborne pathogen surveillance. The lexicon of free-text metadata was evaluated to determine the informational facets and the quantity of unique terms used by data collectors. Open Biological Ontologies (OBO) Foundry libraries were used to develop hierarchical vocabularies that are connected with logical relationships to describe swab site locations. 5 informational facets that were described by 338 unique terms were identified via content analysis. Term hierarchy facets were developed, as were statements (called axioms) about how the entities within these five domains are related. The schema developed through this study has been integrated into a publicly available pathogen metadata standard, facilitating ongoing surveillance and investigations. The One Health Enteric Package was available at NCBI BioSample, beginning in 2022. The collective use of metadata standards increases the interoperability of DNA sequence databases and enables large-scale approaches to data sharing and artificial intelligence as well as big-data solutions to food safety. IMPORTANCE The regular analysis of whole-genome sequence data in collections such as NCBI's Pathogen Detection Database is used by many public health organizations to detect outbreaks of infectious disease. However, isolate metadata in these databases are often incomplete and of poor quality. These complex, raw metadata must often be reorganized and manually formatted for use in aggregate analyses. These processes are inefficient and time-consuming, increasing the interpretative labor needed by public health groups to extract actionable information. The future use of open genomic epidemiology networks will be supported through the development of an internationally applicable vocabulary system with which swab site locations can be described.