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1.
N Engl J Med ; 386(9): 861-868, 2022 03 03.
Article in English | MEDLINE | ID: covidwho-1721753

ABSTRACT

Melioidosis, caused by the bacterium Burkholderia pseudomallei, is an uncommon infection that is typically associated with exposure to soil and water in tropical and subtropical environments. It is rarely diagnosed in the continental United States. Patients with melioidosis in the United States commonly report travel to regions where melioidosis is endemic. We report a cluster of four non-travel-associated cases of melioidosis in Georgia, Kansas, Minnesota, and Texas. These cases were caused by the same strain of B. pseudomallei that was linked to an aromatherapy spray product imported from a melioidosis-endemic area.


Subject(s)
Aromatherapy/adverse effects , Burkholderia pseudomallei/isolation & purification , Disease Outbreaks , Melioidosis/epidemiology , Aerosols , Brain/microbiology , Brain/pathology , Burkholderia pseudomallei/genetics , COVID-19/complications , Child, Preschool , Fatal Outcome , Female , Genome, Bacterial , Humans , Lung/microbiology , Lung/pathology , Male , Melioidosis/complications , Middle Aged , Phylogeny , Shock, Septic/microbiology , United States/epidemiology
2.
J Med Virol ; 94(4): 1670-1688, 2022 04.
Article in English | MEDLINE | ID: covidwho-1718413

ABSTRACT

Bangladesh is experiencing a second wave of COVID-19 since March 2021, despite the nationwide vaccination drive with ChAdOx1 (Oxford-AstraZeneca) vaccine from early February 2021. Here, we characterized 19 nasopharyngeal swab (NPS) samples from COVID-19 suspect patients using genomic and metagenomic approaches. Screening for SARS-CoV-2 by reverse transcriptase polymerase chain reaction and metagenomic sequencing revealed 17 samples of COVID-19 positive (vaccinated = 10, nonvaccinated = 7) and 2 samples of COVID-19 negative. We did not find any significant correlation between associated factors including vaccination status, age or sex of the patients, diversity or abundance of the coinfected organisms/pathogens, and the abundance of SARS-CoV-2. Though the first wave of the pandemic was dominated by clade 20B, Beta, V2 (South African variant) dominated the second wave (January 2021 to May 2021), while the third wave (May 2021 to September 2021) was responsible for Delta variants of the epidemic in Bangladesh including both vaccinated and unvaccinated infections. Noteworthily, the receptor binding domain (RBD) region of S protein of all the isolates harbored similar substitutions including K417N, E484K, and N501Y that signify the Beta, while D614G, D215G, D80A, A67V, L18F, and A701V substitutions were commonly found in the non-RBD region of Spike proteins. ORF7b and ORF3a genes underwent a positive selection (dN/dS ratio 1.77 and 1.24, respectively), while the overall S protein of the Bangladeshi SARS-CoV-2 isolates underwent negative selection pressure (dN/dS = 0.621). Furthermore, we found different bacterial coinfections like Streptococcus agalactiae, Neisseria meningitidis, Elizabethkingia anophelis, Stenotrophomonas maltophilia, Klebsiella pneumoniae, and Pseudomonas plecoglossicida, expressing a number of antibiotic resistance genes such as tetA and tetM. Overall, this approach provides valuable insights on the SARS-CoV-2 genomes and microbiome composition from both vaccinated and nonvaccinated patients in Bangladesh.


Subject(s)
COVID-19/virology , Metagenomics , SARS-CoV-2/genetics , Adolescent , Adult , Aged , Bacteria/classification , Bacteria/genetics , Bacterial Infections/epidemiology , Bacterial Infections/microbiology , Bacterial Infections/virology , Bangladesh/epidemiology , COVID-19/epidemiology , COVID-19/microbiology , COVID-19/prevention & control , Coinfection/epidemiology , Coinfection/microbiology , Coinfection/virology , Drug Resistance, Bacterial/genetics , Female , Genome, Bacterial/genetics , Genome, Viral/genetics , Humans , Male , Microbiota/genetics , Middle Aged , Mutation , Phylogeny , SARS-CoV-2/classification , SARS-CoV-2/isolation & purification , Selection, Genetic , Vaccination , Viral Proteins/genetics , Young Adult
3.
Int J Mol Sci ; 22(16)2021 Aug 22.
Article in English | MEDLINE | ID: covidwho-1372662

ABSTRACT

Natural products of microbial origin have inspired most of the commercial pharmaceuticals, especially those from Actinobacteria. However, the redundancy of molecules in the discovery process represents a serious issue. The untargeted approach, One Strain Many Compounds (OSMAC), is one of the most promising strategies to induce the expression of silent genes, especially when combined with genome mining and advanced metabolomics analysis. In this work, the whole genome of the marine isolate Rhodococcus sp. I2R was sequenced and analyzed by antiSMASH for the identification of biosynthetic gene clusters. The strain was cultivated in 22 different growth media and the generated extracts were subjected to metabolomic analysis and functional screening. Notably, only a single growth condition induced the production of unique compounds, which were partially purified and structurally characterized by liquid chromatography high-resolution tandem mass spectrometry (LC-HRMS/MS). This strategy led to identifying a bioactive fraction containing >30 new glycolipids holding unusual functional groups. The active fraction showed a potent antiviral effect against enveloped viruses, such as herpes simplex virus and human coronaviruses, and high antiproliferative activity in PC3 prostate cancer cell line. The identified compounds belong to the biosurfactants class, amphiphilic molecules, which play a crucial role in the biotech and biomedical industry.


Subject(s)
Antiviral Agents/metabolism , Glycolipids/metabolism , Rhodococcus/metabolism , Animals , Antiviral Agents/analysis , Chlorocebus aethiops , Culture Techniques , Drug Screening Assays, Antitumor , Esters/metabolism , Genome, Bacterial , Glycolipids/chemistry , Humans , Metabolome , Microbial Sensitivity Tests , Molecular Structure , PC-3 Cells , Rhodococcus/chemistry , Rhodococcus/genetics , Succinates/metabolism , Surface-Active Agents/chemistry , Surface-Active Agents/metabolism , Vero Cells
4.
Brief Bioinform ; 22(2): 845-854, 2021 03 22.
Article in English | MEDLINE | ID: covidwho-1343663

ABSTRACT

Humans have coexisted with pathogenic microorganisms throughout its history of evolution. We have never halted the exploration of pathogenic microorganisms. With the improvement of genome-sequencing technology and the continuous reduction of sequencing costs, an increasing number of complete genome sequences of pathogenic microorganisms have become available. Genome annotation of this massive sequence information has become a daunting task in biological research. This paper summarizes the approaches to the genome annotation of pathogenic microorganisms and the available popular genome annotation tools for prokaryotes, eukaryotes and viruses. Furthermore, real-world comparisons of different annotation tools using 12 genomes from prokaryotes, eukaryotes and viruses were conducted. Current challenges and problems were also discussed.


Subject(s)
Genome, Bacterial , Genome, Viral , Molecular Sequence Annotation , Virulence/genetics , Eukaryota/genetics , Humans
5.
Genome Med ; 13(1): 121, 2021 07 28.
Article in English | MEDLINE | ID: covidwho-1331954

ABSTRACT

BACKGROUND: Pathogen whole genome sequencing (WGS) is being incorporated into public health surveillance and disease control systems worldwide and has the potential to make significant contributions to infectious disease surveillance, outbreak investigation and infection prevention and control. However, to date, there are limited data regarding (i) the optimal models for integration of genomic data into epidemiological investigations and (ii) how to quantify and evaluate public health impacts resulting from genomic epidemiological investigations. METHODS: We developed the Pathogen Genomics in Public HeAlth Surveillance Evaluation (PG-PHASE) Framework to guide examination of the use of WGS in public health surveillance and disease control. We illustrate the use of this framework with three pathogens as case studies: Listeria monocytogenes, Mycobacterium tuberculosis and SARS-CoV-2. RESULTS: The framework utilises an adaptable whole-of-system approach towards understanding how interconnected elements in the public health application of pathogen genomics contribute to public health processes and outcomes. The three phases of the PG-PHASE Framework are designed to support understanding of WGS laboratory processes, analysis, reporting and data sharing, and how genomic data are utilised in public health practice across all stages, from the decision to send an isolate or sample for sequencing to the use of sequence data in public health surveillance, investigation and decision-making. Importantly, the phases can be used separately or in conjunction, depending on the need of the evaluator. Subsequent to conducting evaluation underpinned by the framework, avenues may be developed for strategic investment or interventions to improve utilisation of whole genome sequencing. CONCLUSIONS: Comprehensive evaluation is critical to support health departments, public health laboratories and other stakeholders to successfully incorporate microbial genomics into public health practice. The PG-PHASE Framework aims to assist public health laboratories, health departments and authorities who are either considering transitioning to whole genome sequencing or intending to assess the integration of WGS in public health practice, including the capacity to detect and respond to outbreaks and associated costs, challenges and facilitators in the utilisation of microbial genomics and public health impacts.


Subject(s)
Implementation Science , Infections/diagnosis , Listeria monocytogenes/isolation & purification , Mycobacterium tuberculosis/isolation & purification , SARS-CoV-2/isolation & purification , Whole Genome Sequencing/methods , Genome, Bacterial , Genome, Viral , Humans , Infections/epidemiology , Listeria monocytogenes/genetics , Mycobacterium tuberculosis/genetics , Population Surveillance , Public Health , SARS-CoV-2/genetics
6.
J Hosp Infect ; 109: 1-9, 2021 Mar.
Article in English | MEDLINE | ID: covidwho-916875

ABSTRACT

Outbreaks pose a significant risk to patient safety as well as being costly and time consuming to investigate. The implementation of targeted infection prevention and control measures relies on infection prevention and control teams having access to rapid results that detect resistance accurately, and typing results that give clinically useful information on the relatedness of isolates. At present, determining whether transmission has occurred can be a major challenge. Conventional typing results do not always have sufficient granularity or robustness to define strains unequivocally, and sufficient epidemiological data are not always available to establish links between patients and the environment. Whole-genome sequencing (WGS) has emerged as the ultimate genotyping tool, but has not yet fully crossed the divide between research method and routine clinical diagnostic microbiological technique. A clinical WGS service was officially established in 2014 as part of the Scottish Healthcare Associated Infection Prevention Institute to confirm or refute outbreaks in hospital settings from across Scotland. This article describes the authors' experiences with the aim of providing new insights into practical application of the use of WGS to investigate healthcare and public health outbreaks. Solutions to overcome barriers to implementation of this technology in a clinical environment are proposed.


Subject(s)
Disease Outbreaks , Public Health , Whole Genome Sequencing , Delivery of Health Care , Genome, Bacterial , Genotyping Techniques , Humans , Scotland
7.
Diagn Microbiol Infect Dis ; 100(4): 115399, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1315428

ABSTRACT

Between November 2018 and October 2019, carbapenem-resistant Enterobacterales carrying New Delhi Metallo-ß-lactamase (NDM) caused one of the largest and persistent outbreaks occurred in Italy and intensified surveillance measures have been taken in all Italian hospitals. In this study we analyzed NDM-5- producing Escherichia coli identified in 2 hospitals of the Lazio region in Italy. Epidemiological and microbiological data demonstrated that in 2018-2019 the NDM-5-producing high-risk E. coli ST167 clone circulated in patients from both hospitals. In 2019, another NDM-5-producing E. coli clone, identified by MLST as ST617 was introduced in one of the 2 hospitals and caused an outbreak. This study describes an application of genomics as a useful method to discern endemic and outbreak clones when applied to strains of the same species (E. coli) with the same resistance determinant (NDM-5) and the relevance of screening patients admitted in critical units for carbapenemase producers to prevent outbreaks.


Subject(s)
Escherichia coli Infections/epidemiology , Escherichia coli/genetics , beta-Lactamases/genetics , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/pharmacology , DNA, Bacterial/genetics , Disease Outbreaks/prevention & control , Disease Outbreaks/statistics & numerical data , Drug Resistance, Multiple, Bacterial , Escherichia coli/drug effects , Escherichia coli/enzymology , Female , Genome, Bacterial , Hospitals/statistics & numerical data , Humans , Italy/epidemiology , Male , Microbial Sensitivity Tests , Middle Aged , Retrospective Studies , Whole Genome Sequencing , beta-Lactamases/biosynthesis
8.
Microbiologyopen ; 10(3): e1211, 2021 06.
Article in English | MEDLINE | ID: covidwho-1281235

ABSTRACT

Tuberculosis (TB) is the leading cause of death in humans by a single infectious agent worldwide with approximately two billion humans latently infected with the bacterium Mycobacterium tuberculosis. Currently, the accepted method for controlling the disease is Tuberculosis Directly Observed Treatment Shortcourse (TB-DOTS). This program is not preventative and individuals may transmit disease before diagnosis, thus better understanding of disease transmission is essential. Using whole-genome sequencing and single nucleotide polymorphism analysis, we analyzed genomes of 145 M. tuberculosis clinical isolates from active TB cases from the Rubaga Division of Kampala, Uganda. We established that these isolates grouped into M. tuberculosis complex (MTBC) lineages 1, 2, 3, and 4, with the most isolates grouping into lineage 4. Possible transmission pairs containing ≤12 SNPs were identified in lineages 1, 3, and 4 with the prevailing transmission in lineages 3 and 4. Furthermore, investigating DNA codon changes as a result of specific SNPs in prominent virulence genes including plcA and plcB could indicate potentially important modifications in protein function. Incorporating this analysis with corresponding epidemiological data may provide a blueprint for the integration of public health interventions to decrease TB transmission in a region.


Subject(s)
Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/isolation & purification , Polymorphism, Single Nucleotide , Tuberculosis/microbiology , Bacterial Proteins/genetics , Cities/statistics & numerical data , Cross-Sectional Studies , Genome, Bacterial , Genotype , Humans , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/physiology , Phylogeny , Tuberculosis/epidemiology , Tuberculosis/transmission , Uganda/epidemiology , Virulence Factors/genetics , Whole Genome Sequencing
9.
Nature ; 594(7862): 234-239, 2021 06.
Article in English | MEDLINE | ID: covidwho-1269388

ABSTRACT

Loss of gut microbial diversity1-6 in industrial populations is associated with chronic diseases7, underscoring the importance of studying our ancestral gut microbiome. However, relatively little is known about the composition of pre-industrial gut microbiomes. Here we performed a large-scale de novo assembly of microbial genomes from palaeofaeces. From eight authenticated human palaeofaeces samples (1,000-2,000 years old) with well-preserved DNA from southwestern USA and Mexico, we reconstructed 498 medium- and high-quality microbial genomes. Among the 181 genomes with the strongest evidence of being ancient and of human gut origin, 39% represent previously undescribed species-level genome bins. Tip dating suggests an approximate diversification timeline for the key human symbiont Methanobrevibacter smithii. In comparison to 789 present-day human gut microbiome samples from eight countries, the palaeofaeces samples are more similar to non-industrialized than industrialized human gut microbiomes. Functional profiling of the palaeofaeces samples reveals a markedly lower abundance of antibiotic-resistance and mucin-degrading genes, as well as enrichment of mobile genetic elements relative to industrial gut microbiomes. This study facilitates the discovery and characterization of previously undescribed gut microorganisms from ancient microbiomes and the investigation of the evolutionary history of the human gut microbiota through genome reconstruction from palaeofaeces.


Subject(s)
Bacteria/isolation & purification , Biodiversity , Biological Evolution , Feces/microbiology , Gastrointestinal Microbiome , Genome, Bacterial/genetics , Host Microbial Interactions , Anti-Bacterial Agents/administration & dosage , Bacteria/classification , Bacteria/genetics , Chronic Disease , Developed Countries , Developing Countries , Diet, Western , History, Ancient , Humans , Industrial Development/trends , Methanobrevibacter/classification , Methanobrevibacter/genetics , Methanobrevibacter/isolation & purification , Mexico , Sedentary Behavior , Southwestern United States , Species Specificity , Symbiosis
10.
Appl Environ Microbiol ; 87(11)2021 05 11.
Article in English | MEDLINE | ID: covidwho-1225696

ABSTRACT

The widely prescribed pharmaceutical metformin and its main metabolite, guanylurea, are currently two of the most common contaminants in surface and wastewater. Guanylurea often accumulates and is poorly, if at all, biodegraded in wastewater treatment plants. This study describes Pseudomonas mendocina strain GU, isolated from a municipal wastewater treatment plant, using guanylurea as its sole nitrogen source. The genome was sequenced with 36-fold coverage and mined to identify guanylurea degradation genes. The gene encoding the enzyme initiating guanylurea metabolism was expressed, and the enzyme was purified and characterized. Guanylurea hydrolase, a newly described enzyme, was shown to transform guanylurea to one equivalent (each) of ammonia and guanidine. Guanidine also supports growth as a sole nitrogen source. Cell yields from growth on limiting concentrations of guanylurea revealed that metabolism releases all four nitrogen atoms. Genes encoding complete metabolic transformation were identified bioinformatically, defining the pathway as follows: guanylurea to guanidine to carboxyguanidine to allophanate to ammonia and carbon dioxide. The first enzyme, guanylurea hydrolase, is a member of the isochorismatase-like hydrolase protein family, which includes biuret hydrolase and triuret hydrolase. Although homologs, the three enzymes show distinct substrate specificities. Pairwise sequence comparisons and the use of sequence similarity networks allowed fine structure discrimination between the three homologous enzymes and provided insights into the evolutionary origins of guanylurea hydrolase.IMPORTANCE Metformin is a pharmaceutical most prescribed for type 2 diabetes and is now being examined for potential benefits to COVID-19 patients. People taking the drug pass it largely unchanged, and it subsequently enters wastewater treatment plants. Metformin has been known to be metabolized to guanylurea. The levels of guanylurea often exceed that of metformin, leading to the former being considered a "dead-end" metabolite. Metformin and guanylurea are water pollutants of emerging concern, as they persist to reach nontarget aquatic life and humans, the latter if it remains in treated water. The present study has identified a Pseudomonas mendocina strain that completely degrades guanylurea. The genome was sequenced, and the genes involved in guanylurea metabolism were identified in three widely separated genomic regions. This knowledge advances the idea that guanylurea is not a dead-end product and will allow for bioinformatic identification of the relevant genes in wastewater treatment plant microbiomes and other environments subjected to metagenomic sequencing.


Subject(s)
Bacterial Proteins/metabolism , Guanidine/analogs & derivatives , Hydrolases/metabolism , Metabolic Networks and Pathways , Metformin/metabolism , Urea/analogs & derivatives , Water Pollutants, Chemical/metabolism , Ammonia/metabolism , Bacterial Proteins/genetics , Biodegradation, Environmental , Biomineralization , Genome, Bacterial/genetics , Guanidine/metabolism , Hydrolases/genetics , Multigene Family , Pseudomonas mendocina/genetics , Pseudomonas mendocina/isolation & purification , Pseudomonas mendocina/metabolism , Substrate Specificity , Urea/metabolism , Waste Water/microbiology
11.
Science ; 372(6539)2021 04 16.
Article in English | MEDLINE | ID: covidwho-1201427

ABSTRACT

Animals in the wild are able to subsist on pathogen-infected and poisonous food and show immunity to various diseases. These may be due to their microbiota, yet we have a poor understanding of animal microbial diversity and function. We used metagenomics to analyze the gut microbiota of more than 180 species in the wild, covering diverse classes, feeding behaviors, geographies, and traits. Using de novo metagenome assembly, we constructed and functionally annotated a database of more than 5000 genomes, comprising 1209 bacterial species of which 75% are unknown. The microbial composition, diversity, and functional content exhibit associations with animal taxonomy, diet, activity, social structure, and life span. We identify the gut microbiota of wild animals as a largely untapped resource for the discovery of therapeutics and biotechnology applications.


Subject(s)
Animals, Wild/microbiology , Bacteria , Gastrointestinal Microbiome , Genome, Bacterial , Metagenome , Animals , Animals, Wild/classification , Animals, Wild/physiology , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Bacterial Toxins/metabolism , Behavior, Animal , Biodiversity , Databases, Nucleic Acid , Diet , Ecosystem , Falkland Islands , Feces/microbiology , Host Microbial Interactions , Israel , Madagascar , Metagenomics , Peptide Hydrolases/genetics , Peptide Hydrolases/metabolism , Phylogeny , Queensland , Uganda
12.
Proc Natl Acad Sci U S A ; 118(18)2021 05 04.
Article in English | MEDLINE | ID: covidwho-1189344

ABSTRACT

As the coronavirus disease 2019 (COVID-19) pandemic rages on, it is important to explore new evolution-resistant vaccine antigens and new vaccine platforms that can produce readily scalable, inexpensive vaccines with easier storage and transport. We report here a synthetic biology-based vaccine platform that employs an expression vector with an inducible gram-negative autotransporter to express vaccine antigens on the surface of genome-reduced bacteria to enhance interaction of vaccine antigen with the immune system. As a proof-of-principle, we utilized genome-reduced Escherichia coli to express SARS-CoV-2 and porcine epidemic diarrhea virus (PEDV) fusion peptide (FP) on the cell surface, and evaluated their use as killed whole-cell vaccines. The FP sequence is highly conserved across coronaviruses; the six FP core amino acid residues, along with the four adjacent residues upstream and the three residues downstream from the core, are identical between SARS-CoV-2 and PEDV. We tested the efficacy of PEDV FP and SARS-CoV-2 FP vaccines in a PEDV challenge pig model. We demonstrated that both vaccines induced potent anamnestic responses upon virus challenge, potentiated interferon-γ responses, reduced viral RNA loads in jejunum tissue, and provided significant protection against clinical disease. However, neither vaccines elicited sterilizing immunity. Since SARS-CoV-2 FP and PEDV FP vaccines provided similar clinical protection, the coronavirus FP could be a target for a broadly protective vaccine using any platform. Importantly, the genome-reduced bacterial surface-expressed vaccine platform, when using a vaccine-appropriate bacterial vector, has potential utility as an inexpensive, readily manufactured, and rapid vaccine platform for other pathogens.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , Porcine epidemic diarrhea virus/immunology , SARS-CoV-2/immunology , Viral Fusion Proteins/immunology , Viral Vaccines/immunology , Animals , Antibodies, Viral/blood , Disease Models, Animal , Escherichia coli/genetics , Genome, Bacterial , Interferon-gamma/blood , RNA, Viral/analysis , Swine , Vaccines, Inactivated/immunology , Vaccines, Synthetic/immunology
13.
Front Cell Infect Microbiol ; 11: 641920, 2021.
Article in English | MEDLINE | ID: covidwho-1170079

ABSTRACT

Pseudomonas aeruginosa is a biofilm-forming opportunistic pathogen which causes chronic infections in immunocompromised patients and leads to high mortality rate. It is identified as a common coinfecting pathogen in COVID-19 patients causing exacerbation of illness. In our hospital, P. aeruginosa is one of the top coinfecting bacteria identified among COVID-19 patients. We collected a strong biofilm-forming P. aeruginosa strain displaying small colony variant morphology from a severe COVID-19 patient. Genomic and transcriptomic sequencing analyses were performed with phenotypic validation to investigate its adaptation in SARS-CoV-2 infected environment. Genomic characterization predicted specific genomic islands highly associated with virulence, transcriptional regulation, and DNA restriction-modification systems. Epigenetic analysis revealed a specific N6-methyl adenine (m6A) methylating pattern including methylation of alginate, flagellar and quorum sensing associated genes. Differential gene expression analysis indicated that this isolate formed excessive biofilm by reducing flagellar formation (7.4 to 1,624.1 folds) and overproducing extracellular matrix components including CdrA (4.4 folds), alginate (5.2 to 29.1 folds) and Pel (4.8-5.5 folds). In summary, we demonstrated that P. aeuginosa clinical isolates with novel epigenetic markers could form excessive biofilm, which might enhance its antibiotic resistance and in vivo colonization in COVID-19 patients.


Subject(s)
Adaptation, Physiological/physiology , COVID-19/complications , Coinfection/complications , Pseudomonas Infections/complications , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/metabolism , Adhesins, Bacterial/genetics , Adhesins, Bacterial/metabolism , Alginates , Bacteria , Biofilms/growth & development , DNA Methylation , Epigenomics , Gene Expression Profiling , Gene Expression Regulation, Bacterial , Genome, Bacterial , Humans , Pseudomonas Infections/immunology , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/classification , Quorum Sensing/genetics , SARS-CoV-2 , Transcriptome , Virulence
14.
Curr Biol ; 30(19): R1124-R1130, 2020 10 05.
Article in English | MEDLINE | ID: covidwho-813541

ABSTRACT

Since the first recognition that infectious microbes serve as the causes of many human diseases, physicians and scientists have sought to understand and control their spread. For the past 150+ years, these 'microbe hunters' have learned to combine epidemiological information with knowledge of the infectious agent(s). In this essay, I reflect on the evolution of microbe hunting, beginning with the history of pre-germ theory epidemiological studies, through the microbiological and molecular eras. Now in the genomic age, modern-day microbe hunters are combining pathogen whole-genome sequencing with epidemiological data to enhance epidemiological investigations, advance our understanding of the natural history of pathogens and drivers of disease, and ultimately reshape our plans and priorities for global disease control and eradication. Indeed, as we have seen during the ongoing Covid-19 pandemic, the role of microbe hunters is now more important than ever. Despite the advances already made by microbial genomic epidemiology, the field is still maturing, with many more exciting developments on the horizon.


Subject(s)
Bacteria/genetics , Bacterial Infections/diagnosis , Bacterial Infections/epidemiology , Molecular Epidemiology/methods , Primary Prevention/methods , Bacteria/pathogenicity , Betacoronavirus/genetics , Betacoronavirus/pathogenicity , COVID-19 , Coronavirus Infections/epidemiology , Genome, Bacterial/genetics , Genome, Viral/genetics , History, 19th Century , History, 20th Century , Humans , Microbiota/genetics , Pandemics , Pneumonia, Viral/epidemiology , SARS-CoV-2
15.
Antimicrob Resist Infect Control ; 9(1): 154, 2020 09 22.
Article in English | MEDLINE | ID: covidwho-781536

ABSTRACT

BACKGROUND: Currently, hospitals have been forced to divert substantial resources to cope with the ongoing coronavirus disease 2019 (COVID-19) pandemic. It is unclear if this situation will affect long-standing infection prevention practices and impact on healthcare associated infections. Here, we report a nosocomial cluster of vancomycin-resistant enterococci (VRE) that occurred on a COVID-19 dedicated intensive care unit (ICU) despite intensified contact precautions during the current pandemic. Whole genome sequence-based typing (WGS) was used to investigate genetic relatedness of VRE isolates collected from COVID-19 and non-COVID-19 patients during the outbreak and to compare them to environmental VRE samples. METHODS: Five VRE isolated from patients (three clinical and two screening samples) as well as 11 VRE and six vancomycin susceptible Enterococcus faecium (E. faecium) samples from environmental sites underwent WGS during the outbreak investigation. Isolate relatedness was determined using core genome multilocus sequence typing (cgMLST). RESULTS: WGS revealed two genotypic distinct VRE clusters with genetically closely related patient and environmental isolates. The cluster was terminated by enhanced infection control bundle strategies. CONCLUSIONS: Our results illustrate the importance of continued adherence to infection prevention and control measures during the COVID-19 pandemic to prevent VRE transmission and healthcare associated infections.


Subject(s)
Coinfection/drug therapy , Cross Infection/epidemiology , Gram-Positive Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/epidemiology , Vancomycin-Resistant Enterococci/drug effects , Betacoronavirus , COVID-19 , Coinfection/microbiology , Coronavirus Infections/pathology , Cross Infection/drug therapy , Cross Infection/microbiology , Disease Outbreaks , Genome, Bacterial/genetics , Gram-Positive Bacterial Infections/microbiology , Humans , Infection Control , Intensive Care Units , Multilocus Sequence Typing , Pandemics , Pneumonia, Viral/pathology , Primary Prevention , SARS-CoV-2 , Vancomycin-Resistant Enterococci/genetics , Vancomycin-Resistant Enterococci/isolation & purification , Whole Genome Sequencing
16.
Proc Natl Acad Sci U S A ; 117(29): 17195-17203, 2020 07 21.
Article in English | MEDLINE | ID: covidwho-624792

ABSTRACT

The vast majority of intracellular protein targets are refractory toward small-molecule therapeutic engagement, and additional therapeutic modalities are needed to overcome this deficiency. Here, the identification and characterization of a natural product, WDB002, reveals a therapeutic modality that dramatically expands the currently accepted limits of druggability. WDB002, in complex with the FK506-binding protein (FKBP12), potently and selectively binds the human centrosomal protein 250 (CEP250), resulting in disruption of CEP250 function in cells. The recognition mode is unprecedented in that the targeted domain of CEP250 is a coiled coil and is topologically featureless, embodying both a structural motif and surface topology previously considered on the extreme limits of "undruggability" for an intracellular target. Structural studies reveal extensive protein-WDB002 and protein-protein contacts, with the latter being distinct from those seen in FKBP12 ternary complexes formed by FK506 and rapamycin. Outward-facing structural changes in a bound small molecule can thus reprogram FKBP12 to engage diverse, otherwise "undruggable" targets. The flat-targeting modality demonstrated here has the potential to expand the druggable target range of small-molecule therapeutics. As CEP250 was recently found to be an interaction partner with the Nsp13 protein of the SARS-CoV-2 virus that causes COVID-19 disease, it is possible that WDB002 or an analog may exert useful antiviral activity through its ability to form high-affinity ternary complexes containing CEP250 and FKBP12.


Subject(s)
Actinobacteria/genetics , Antiviral Agents/pharmacology , Genome, Bacterial , Macrolides/pharmacology , Protein Interaction Domains and Motifs/drug effects , Small Molecule Libraries/pharmacology , Tacrolimus Binding Protein 1A/chemistry , Tacrolimus Binding Protein 1A/metabolism , Actinobacteria/metabolism , Amino Acid Sequence , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Autoantigens/genetics , Autoantigens/metabolism , Calcineurin/genetics , Calcineurin/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Evolution, Molecular , HEK293 Cells , Humans , Macrolides/chemistry , Macrolides/metabolism , Models, Molecular , Protein Conformation , Sequence Homology , Sirolimus/chemistry , Sirolimus/metabolism , Small Molecule Libraries/chemistry , Small Molecule Libraries/metabolism , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism
17.
J Bacteriol ; 202(12)2020 05 27.
Article in English | MEDLINE | ID: covidwho-684313

ABSTRACT

Bacteriocins are ribosomally synthesized proteinaceous antibacterial peptides. They selectively interfere with the growth of other bacteria. The production and secretion of bacteriocins confer a distinct ecological advantage to the producer in competing against other bacteria that are present in the same ecological niche. Streptococcus mutans, a significant contributor to the development of dental caries, is one of the most prolific producers of bacteriocins, known as mutacins in S. mutans In this study, we characterized the locus encoding mutacin B-Ny266, a lantibiotic with a broad spectrum of activity. The chromosomal locus is composed of six predicted operon structures encoding proteins involved in regulation, antimicrobial activity, biosynthesis, modification, transport, and immunity. Mutacin B-Ny266 was purified from semisolid cultures, and two inhibitory peptides, LanA and LanA', were detected. Both peptides were highly modified. Such modifications include dehydration of serine and threonine and the formation of a C-terminal aminovinyl-cysteine (AviCys) ring. While LanA peptide alone is absolutely required for antimicrobial activity, the presence of LanA' enhanced the activity of LanA, suggesting that B-Ny266 may function as a two-peptide lantibiotic. The activation of lanAA' expression is most likely controlled by the conserved two-component system NsrRS, which is activated by LanA peptide but not by LanA'. The chromosomal locus encoding mutacin B-Ny266 was not universally conserved in all sequenced S. mutans genomes. Intriguingly, the genes encoding LanAA' peptides were restricted to the most invasive serotypes of S. mutans IMPORTANCE Although dental caries is largely preventable, it remains the most common and costly infectious disease worldwide. Caries is initiated by the presence of dental plaque biofilm that contains Streptococcus mutans, a species extensively characterized by its role in caries development and formation. S. mutans deploys an arsenal of strategies to establish itself within the oral cavity. One of them is the production of bacteriocins that confer a competitive advantage by targeting and killing closely related competitors. In this work, we found that mutacin B-Ny266 is a potent lantibiotic that is effective at killing a wide array of oral streptococci, including nearly all S. mutans strains tested. Lantibiotics produced by oral bacteria could represent a promising strategy to target caries pathogens embedded in dental plaque biofilm.


Subject(s)
Anti-Bacterial Agents/biosynthesis , Bacterial Proteins/genetics , Bacteriocins/biosynthesis , Dental Caries/microbiology , Streptococcus mutans/genetics , Streptococcus mutans/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Bacteriocins/pharmacology , Genome, Bacterial , Humans , Operon , Streptococcus mutans/drug effects , Streptococcus mutans/growth & development
18.
Int J Mol Sci ; 21(11)2020 May 29.
Article in English | MEDLINE | ID: covidwho-436912

ABSTRACT

Advances in sequencing technology have made large amounts of biological data available. Evolutionary analysis of data such as DNA sequences is highly important in biological studies. As alignment methods are ineffective for analyzing large-scale data due to their inherently high costs, alignment-free methods have recently attracted attention in the field of bioinformatics. In this paper, we introduce a new positional correlation natural vector (PCNV) method that involves converting a DNA sequence into an 18-dimensional numerical feature vector. Using frequency and position correlation to represent the nucleotide distribution, it is possible to obtain a PCNV for a DNA sequence. This new numerical vector design uses six suitable features to characterize the correlation among nucleotide positions in sequences. PCNV is also very easy to compute and can be used for rapid genome comparison. To test our novel method, we performed phylogenetic analysis with several viral and bacterial genome datasets with PCNV. For comparison, an alignment-based method, Bayesian inference, and two alignment-free methods, feature frequency profile and natural vector, were performed using the same datasets. We found that the PCNV technique is fast and accurate when used for phylogenetic analysis and classification of viruses and bacteria.


Subject(s)
Phylogeny , Sequence Analysis, DNA/methods , Sequence Homology, Nucleic Acid , Algorithms , Genome, Bacterial , Genome, Viral , Sequence Alignment
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