1
|
Graham KA, Gomez J, Primm TP, Houston R. Comparison of nine extraction methods for bacterial identification using the ONT MinION sequencer. Int J Legal Med 2024; 138:351-360. [PMID: 37775594 DOI: 10.1007/s00414-023-03092-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 09/18/2023] [Indexed: 10/01/2023]
Abstract
The Anthrax mailings bioterrorism attack in 2001 revealed the need for universal and rapid microbial forensic analyses on unknown biological evidence. However, the gold standard for bacterial identification includes culturing isolates, which is laborious. Molecular approaches for bacterial identification revolve around 16S ribosomal gene sequencing using Sanger or next generation sequencing (NGS) platforms, but these techniques are laboratory-based and can also be time-consuming. The Oxford Nanopore Technologies (ONT) MinION sequencer can generate long read lengths that span the entire bacterial 16S rRNA gene and accurately identify the species level. This platform can be used in the field, allowing on-site evidence analysis. However, it requires higher quantities of pure DNA compared to other sequencing platforms; thus, the extraction method for bacterial DNA is critical for downstream analysis, which to date are tailored toward a priori knowledge of the species' taxonomic grouping. During an attack, the investigative team may not know what species they are handling; therefore, identifying an extraction method that can handle all bacterial groups and generate clean DNA for the MinION is useful for microbial forensic analysis. The purpose of this study was to identify a "universal" extraction method that can be coupled with ONT MinION sequencing for use in forensic situations for rapid identification. It also evaluated the cloud-based data analysis software provided by ONT, EPI2ME. No "universal" extraction method was identified as optimal for downstream MinION sequencing. However, the DNeasy PowerSoil Kit and Noda et al. Chelex-100 method gave comparable sequencing results and could be used as rapid extraction techniques. This study showed that the ONT 16S Barcoding Kit 1-24 coupled with the 16S FASTQ workflow might not be the best for use in forensic situations where species-level identification needs to be obtained, as most alignments were approximately 89% accurate. In all seven test organisms and nine extraction methods, accurate species identification was only obtained in 63% of the cases.
Collapse
Affiliation(s)
- Kari A Graham
- Department of Forensic Science, College of Criminal Justice, Sam Houston State University, 1003 Bowers Blvd., Huntsville, TX, 77340-2525, USA
| | - Javier Gomez
- Department of Biological Sciences, College of Science and Engineering Technology, Sam Houston State University, 2000 Ave I, Huntsville, TX, 77341, USA
| | - Todd P Primm
- Department of Biological Sciences, College of Science and Engineering Technology, Sam Houston State University, 2000 Ave I, Huntsville, TX, 77341, USA
| | - Rachel Houston
- Department of Forensic Science, College of Criminal Justice, Sam Houston State University, 1003 Bowers Blvd., Huntsville, TX, 77340-2525, USA.
| |
Collapse
|
2
|
Liu W, Tang JW, Mou JY, Lyu JW, Di YW, Liao YL, Luo YF, Li ZK, Wu X, Wang L. Rapid discrimination of Shigella spp. and Escherichia coli via label-free surface enhanced Raman spectroscopy coupled with machine learning algorithms. Front Microbiol 2023; 14:1101357. [PMID: 36970678 PMCID: PMC10030586 DOI: 10.3389/fmicb.2023.1101357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 02/20/2023] [Indexed: 03/11/2023] Open
Abstract
Shigella and enterotoxigenic Escherichia coli (ETEC) are major bacterial pathogens of diarrheal disease that is the second leading cause of childhood mortality globally. Currently, it is well known that Shigella spp., and E. coli are very closely related with many common characteristics. Evolutionarily speaking, Shigella spp., are positioned within the phylogenetic tree of E. coli. Therefore, discrimination of Shigella spp., from E. coli is very difficult. Many methods have been developed with the aim of differentiating the two species, which include but not limited to biochemical tests, nucleic acids amplification, and mass spectrometry, etc. However, these methods suffer from high false positive rates and complicated operation procedures, which requires the development of novel methods for accurate and rapid identification of Shigella spp., and E. coli. As a low-cost and non-invasive method, surface enhanced Raman spectroscopy (SERS) is currently under intensive study for its diagnostic potential in bacterial pathogens, which is worthy of further investigation for its application in bacterial discrimination. In this study, we focused on clinically isolated E. coli strains and Shigella species (spp.), that is, S. dysenteriae, S. boydii, S. flexneri, and S. sonnei, based on which SERS spectra were generated and characteristic peaks for Shigella spp., and E. coli were identified, revealing unique molecular components in the two bacterial groups. Further comparative analysis of machine learning algorithms showed that, the Convolutional Neural Network (CNN) achieved the best performance and robustness in bacterial discrimination capacity when compared with Random Forest (RF) and Support Vector Machine (SVM) algorithms. Taken together, this study confirmed that SERS paired with machine learning could achieve high accuracy in discriminating Shigella spp., from E. coli, which facilitated its application potential for diarrheal prevention and control in clinical settings.
Collapse
Affiliation(s)
- Wei Liu
- School of Medical Informatics and Engineering, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Jia-Wei Tang
- School of Medical Informatics and Engineering, Xuzhou Medical University, Xuzhou, Jiangsu, China
- Laboratory Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Jing-Yi Mou
- The First School of Clinical Medicine, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Jing-Wen Lyu
- Laboratory Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Yu-Wei Di
- Laboratory Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Ya-Long Liao
- Laboratory Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Yan-Fei Luo
- Laboratory Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Zheng-Kang Li
- Laboratory Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
- *Correspondence: Zheng-Kang Li,
| | - Xiang Wu
- School of Medical Informatics and Engineering, Xuzhou Medical University, Xuzhou, Jiangsu, China
- Xiang Wu,
| | - Liang Wang
- Laboratory Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
- Liang Wang,
| |
Collapse
|
3
|
Pereira Zanetti JP, Peres Oliveira L, Chindelevitch L, Meidanis J. Generalizations of the genomic rank distance to indels. Bioinformatics 2023; 39:7039678. [PMID: 36790056 PMCID: PMC9985151 DOI: 10.1093/bioinformatics/btad087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 12/25/2022] [Accepted: 02/13/2023] [Indexed: 02/16/2023] Open
Abstract
MOTIVATION The rank distance model represents genome rearrangements in multi-chromosomal genomes as matrix operations, which allows the reconstruction of parsimonious histories of evolution by rearrangements. We seek to generalize this model by allowing for genomes with different gene content, to accommodate a broader range of biological contexts. We approach this generalization by using a matrix representation of genomes. This leads to simple distance formulas and sorting algorithms for genomes with different gene contents, but without duplications. RESULTS We generalize the rank distance to genomes with different gene content in two different ways. The first approach adds insertions, deletions and the substitution of a single extremity to the basic operations. We show how to efficiently compute this distance. To avoid genomes with incomplete markers, our alternative distance, the rank-indel distance, only uses insertions and deletions of entire chromosomes. We construct phylogenetic trees with our distances and the DCJ-Indel distance for simulated data and real prokaryotic genomes, and compare them against reference trees. For simulated data, our distances outperform the DCJ-Indel distance using the Quartet metric as baseline. This suggests that rank distances are more robust for comparing distantly related species. For real prokaryotic genomes, all rearrangement-based distances yield phylogenetic trees that are topologically distant from the reference (65% similarity with Quartet metric), but are able to cluster related species within their respective clades and distinguish the Shigella strains as the farthest relative of the Escherichia coli strains, a feature not seen in the reference tree. AVAILABILITY AND IMPLEMENTATION Code and instructions are available at https://github.com/meidanis-lab/rank-indel. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
| | | | - Leonid Chindelevitch
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College, London, UK
| | - João Meidanis
- Institute of Computing, University of Campinas, Campinas, Brazil
| |
Collapse
|
4
|
Halimeh FB, Rafei R, Osman M, Kassem II, Diene SM, Dabboussi F, Rolain JM, Hamze M. Historical, current, and emerging tools for identification and serotyping of Shigella. Braz J Microbiol 2021; 52:2043-2055. [PMID: 34524650 PMCID: PMC8441030 DOI: 10.1007/s42770-021-00573-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 06/29/2021] [Indexed: 11/17/2022] Open
Abstract
The Shigella genus includes serious foodborne disease etiologic agents, with 4 species and 54 serotypes. Identification at species and serotype levels is a crucial task in microbiological laboratories. Nevertheless, the genetic similarity between Shigella spp. and Escherichia coli challenges the correct identification and serotyping of Shigella spp., with subsequent negative repercussions on surveillance, epidemiological investigations, and selection of appropriate treatments. For this purpose, multiple techniques have been developed historically ranging from phenotype-based methods and single or multilocus molecular techniques to whole-genome sequencing (WGS). To facilitate the selection of the most relevant method, we herein provide a global overview of historical and emerging identification and serotyping techniques with a particular focus on the WGS-based approaches. This review highlights the excellent discriminatory power of WGS to more accurately elucidate the epidemiology of Shigella spp., disclose novel promising genomic targets for surveillance methods, and validate previous well-established methods.
Collapse
Affiliation(s)
- Fatima Bachir Halimeh
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Sciences and Technology, Faculty of Public Health, Lebanese University, Tripoli, Lebanon.,Aix-Marseille University, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Faculté de Médecine Et de Pharmacie, 19-21 boulevard Jean Moulin, 13385, Marseille CEDEX 05, France
| | - Rayane Rafei
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Sciences and Technology, Faculty of Public Health, Lebanese University, Tripoli, Lebanon
| | - Marwan Osman
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Sciences and Technology, Faculty of Public Health, Lebanese University, Tripoli, Lebanon.,Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14850, USA
| | - Issmat I Kassem
- Center for Food Safety and Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, GA, 30223-1797, USA
| | - Seydina M Diene
- Aix-Marseille University, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Faculté de Médecine Et de Pharmacie, 19-21 boulevard Jean Moulin, 13385, Marseille CEDEX 05, France
| | - Fouad Dabboussi
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Sciences and Technology, Faculty of Public Health, Lebanese University, Tripoli, Lebanon
| | - Jean-Marc Rolain
- Aix-Marseille University, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Faculté de Médecine Et de Pharmacie, 19-21 boulevard Jean Moulin, 13385, Marseille CEDEX 05, France
| | - Monzer Hamze
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Sciences and Technology, Faculty of Public Health, Lebanese University, Tripoli, Lebanon.
| |
Collapse
|
5
|
CVTree: A Parallel Alignment-free Phylogeny and Taxonomy Tool based on Composition Vectors of Genomes. GENOMICS PROTEOMICS & BIOINFORMATICS 2021; 19:662-667. [PMID: 34119695 PMCID: PMC9040009 DOI: 10.1016/j.gpb.2021.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 02/23/2021] [Accepted: 03/06/2021] [Indexed: 11/21/2022]
Abstract
CVTree is an alignment-free algorithm to infer phylogenetic relationships from genome sequences. It had been successfully applied to study phylogeny and taxonomy of viruses, prokaryotes, and fungi based on the whole genomes, as well as chloroplasts, mitochondria, and metagenomes. Here we presented the standalone software for the CVTree algorithm. In the software, an extensible parallel workflow for the CVTree algorithm was designed. Based on the workflow, new alignment-free methods were also implemented. And by examining the phylogeny and taxonomy of 13,903 prokaryotes based on 16S rRNA sequences, we showed that CVTree software is an efficient and effective tool for the studying of phylogeny and taxonomy based on genome sequences. Code availability: https://github.com/ghzuo/cvtree.
Collapse
|
6
|
García A, Fox JG. A One Health Perspective for Defining and Deciphering Escherichia coli Pathogenic Potential in Multiple Hosts. Comp Med 2021; 71:3-45. [PMID: 33419487 PMCID: PMC7898170 DOI: 10.30802/aalas-cm-20-000054] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/17/2020] [Accepted: 09/19/2020] [Indexed: 11/05/2022]
Abstract
E. coli is one of the most common species of bacteria colonizing humans and animals. The singularity of E. coli 's genus and species underestimates its multifaceted nature, which is represented by different strains, each with different combinations of distinct virulence factors. In fact, several E. coli pathotypes, or hybrid strains, may be associated with both subclinical infection and a range of clinical conditions, including enteric, urinary, and systemic infections. E. coli may also express DNA-damaging toxins that could impact cancer development. This review summarizes the different E. coli pathotypes in the context of their history, hosts, clinical signs, epidemiology, and control. The pathotypic characterization of E. coli in the context of disease in different animals, including humans, provides comparative and One Health perspectives that will guide future clinical and research investigations of E. coli infections.
Collapse
Key Words
- aa, aggregative adherence
- a/e, attaching and effacing
- aepec, atypical epec
- afa, afimbrial adhesin
- aida-i, adhesin involved in diffuse adherence
- aiec, adherent invasive e. coli
- apec, avian pathogenic e. coli
- atcc, american type culture collection
- bfp, bundle-forming pilus
- cd, crohn disease
- cdt, cytolethal distending toxin gene
- clb, colibactin
- cnf, cytotoxic necrotizing factor
- cs, coli surface (antigens)
- daec, diffusely adhering e. coli
- db, dutch belted
- eae, e. coli attaching and effacing gene
- eaec, enteroaggregative e. coli
- eaf, epec adherence factor (plasmid)
- eahec, entero-aggregative-hemorrhagic e. coli
- east-1, enteroaggregative e. coli heat-stable enterotoxin
- e. coli, escherichia coli
- ed, edema disease
- ehec, enterohemorrhagic e. coli
- eiec, enteroinvasive e. coli
- epec, enteropathogenic e. coli
- esbl, extended-spectrum β-lactamase
- esp, e. coli secreted protein
- etec, enterotoxigenic e. coli
- expec, extraintestinal pathogenic e. coli
- fyua, yersiniabactin receptor gene
- gi, gastrointestinal
- hly, hemolysin
- hus, hemolytic uremic syndrome
- ibd, inflammatory bowel disease
- la, localized adherence
- lee, locus of enterocyte effacement
- lpf, long polar fimbriae
- lt, heat-labile (enterotoxin)
- mlst, multilocus sequence typing
- ndm, new delhi metallo-β-lactamase
- nzw, new zealand white
- pap, pyelonephritis-associated pilus
- pks, polyketide synthase
- sfa, s fimbrial adhesin
- slt, shiga-like toxin
- st, heat-stable (enterotoxin)
- stec, stx-producing e. coli
- stx, shiga toxin
- tepec, typical epec
- upec, uropathogenic e. coli
- uti, urinary tract infection
Collapse
Affiliation(s)
- Alexis García
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico; Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts; Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts;,
| | - James G Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| |
Collapse
|
7
|
Dietary l-arginine supplementation ameliorates inflammatory response and alters gut microbiota composition in broiler chickens infected with Salmonella enterica serovar Typhimurium. Poult Sci 2020; 99:1862-1874. [PMID: 32241466 PMCID: PMC7587704 DOI: 10.1016/j.psj.2019.10.049] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 10/13/2019] [Accepted: 10/21/2019] [Indexed: 12/24/2022] Open
Abstract
This study was conducted to investigate the effects of dietary arginine (Arg) supplementation on the inflammatory response and gut microbiota of broiler chickens subjected to Salmonella enterica serovar Typhimurium. One hundred and forty 1-day-old Arbor Acres male birds were randomly assigned to a 2 × 2 factorial arrangement including diet treatment (with or without 0.3% Arg supplementation) and immunological stress (with or without S. typhimurium challenge). Samples were obtained at 7 D after infection (day 23). Results showed that S. typhimurium challenge caused histopathological and morphological damages, but Arg addition greatly reduced these intestinal injuries. S. typhimurium challenge elevated the levels of serum inflammatory parameters, including diamine oxidase, C-reactive protein, procalcitonin, IL-1β, IL-8, and lipopolysaccharide-induced tumor necrosis factor-alpha factor (LITNF) homolog. However, Arg supplementation decreased the serum procalcitonin, IL-1β, IL-8, and LITNF concentration. S. typhimurium challenge significantly increased jejunal IL-1β, IL-8, IL-10, and IL-17 mRNA expression and tended to upregulate IL-22 mRNA expression, but Arg supplementation remarkably reduced IL-8 mRNA expression, tended to downregulate IL-22 mRNA expression, and dramatically elevated IFN-γ and IL-10 mRNA expression. In addition, sequencing data of 16S rDNA indicated that the population of Proteobacteria phylum; Enterobacteriaceae family; Escherichia–Shigella, and Nitrosomonas genera; and Escherichia coli and Ochrobactrum intermedium species were more abundant, but the population of Rhodocyclaceae and Clostridiaceae_1 families and Candidatus Arthromitus genus were less abundant in the ileal digesta of birds with only S. typhimurium infection when compared with the controls. Treatment with Arg in birds subjected to S. typhimurium challenge increased the abundances of Firmicutes phylum, Clostridiaceae_1 family, Methylobacterium and Candidatus Arthromitus genera but decreased the abundance of Nitrosomonas genus and Rhizobium cellulosilyticum and Rubrobacter xylanophilus species as compared with the only S. typhimurium–challenged birds. In conclusion, Arg supplementation can alleviate intestinal mucosal impairment by ameliorating inflammatory response and modulating gut microbiota in broiler chickens challenged with S. typhimurium.
Collapse
|
8
|
Ma Q, Li Y, Wang J, Li P, Duan Y, Dai H, An Y, Cheng L, Wang T, Wang C, Wang T, Zhao B. Investigation of gut microbiome changes in type 1 diabetic mellitus rats based on high-throughput sequencing. Biomed Pharmacother 2020; 124:109873. [PMID: 31986412 DOI: 10.1016/j.biopha.2020.109873] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 01/03/2020] [Accepted: 01/10/2020] [Indexed: 12/13/2022] Open
Abstract
The incidence of type 1 diabetes mellitus (T1DM) is increasing year by year, gut microbiota is considered to be closely related to the occurrence and development of T1DM in recent years. In this study, Sprague Dawley (SD) rats were intraperitoneally injected with 75mg/kg streptozotocin to establish T1DM model, fecal samples were collected and DNA were extracted, 16S rRNA microbial gene clone library were constructed, and lastly high-throughput sequencing and bioinformatics analysis were performed. The results showed that the abundances of pathogenic bacteria such as Ruminococcaceae, Shigella, Enterococcus, Streptococcus, Rothia and Alistipes associated with infection and inflammation in T1DM rats were up-regulated, while the abundances of beneficial bacteria such as Lactobacillus, Faecalitalea, Butyricicoccus and Allobaculum were reduced. Among them, Butyricicoccus and Allobaculum protect intestinal barrier function by producing short-chain fatty acids. This study suggests that intestinal inflammation and reduction of short chain fatty acids (SCFAs) caused by the imbalance of gut microbiota are crucial to the pathogenesis of T1DM.
Collapse
MESH Headings
- Animals
- Bacteria/isolation & purification
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/microbiology
- Diabetes Mellitus, Experimental/physiopathology
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/microbiology
- Diabetes Mellitus, Type 1/physiopathology
- Fatty Acids, Volatile/metabolism
- Gastrointestinal Microbiome
- High-Throughput Nucleotide Sequencing
- Inflammation/genetics
- Inflammation/microbiology
- Inflammation/pathology
- Male
- RNA, Ribosomal, 16S
- Rats
- Rats, Sprague-Dawley
- Streptozocin
Collapse
Affiliation(s)
- Quantao Ma
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No.11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Yaqi Li
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No.11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Jingkang Wang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No.11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Pengfei Li
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No.11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Yuhui Duan
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No.11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Hongyu Dai
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No.11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Yongcheng An
- School of Life Sciences, Beijing University of Chinese Medicine, Intersection of Yang-Guang South Street and Bai-Yang East Road, Fang-Shan District, Beijing, 102488, China
| | - Long Cheng
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No.11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Tieshan Wang
- Beijing Research Institute of Chinese Medicine, Beijing University of Chinese Medicine, No. 11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Chunguo Wang
- Beijing Research Institute of Chinese Medicine, Beijing University of Chinese Medicine, No. 11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China
| | - Ting Wang
- Beijing Research Institute of Chinese Medicine, Beijing University of Chinese Medicine, No. 11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China.
| | - Baosheng Zhao
- Beijing Research Institute of Chinese Medicine, Beijing University of Chinese Medicine, No. 11 North 3rd Ring East Road, Chao-Yang District, Beijing, 100029, China.
| |
Collapse
|
9
|
Tindall BJ. Rule 24b of the International Code of Nomenclature of Prokaryotes and regulating the priority of names and epithets considered to be associated with heterotypic synonyms. Int J Syst Evol Microbiol 2019; 69:3980-3983. [PMID: 31219419 DOI: 10.1099/ijsem.0.003531] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Rule 24b of the International Code of Nomenclature of Prokaryotes regulates the priority of names that are considered to be heterotypic synonyms. However, the rule is imperfect because it caters only for names that compete for priority that were only included on the Approved Lists of Bacterial Names or for names that were only validly published in the International Journal of Systematic Bacteriology or the International Journal of Systematic and Evolutionary Microbiology, either in an original article or via the Validation Lists. Although this should be self-explanatory, Rule 24b does not cater for what happens when one or more names considered to be heterotypic synonyms have appeared on the Approved Lists of Bacterial Names while other names also considered to be heterotypic synonyms were validly published in the International Journal of Systematic Bacteriology or the International Journal of Systematic and Evolutionary Microbiology, either in an original article or via the Validation Lists. Formal changes to the International Code of Nomenclature of Prokaryotes are required.
Collapse
Affiliation(s)
- B J Tindall
- Liebniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen Gmbh., Inhoffenstraße 7B, 38124 Braunschweig, Germany
| |
Collapse
|
10
|
Rautureau GJP, Palama TL, Canard I, Mirande C, Chatellier S, van Belkum A, Elena-Herrmann B. Discrimination of Escherichia coli and Shigella spp. by Nuclear Magnetic Resonance Based Metabolomic Characterization of Culture Media. ACS Infect Dis 2019; 5:1879-1886. [PMID: 31545890 DOI: 10.1021/acsinfecdis.9b00199] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Dysentery is a major health threat that dramatically impacts childhood morbidity and mortality in developing countries. Various pathogenic agents cause dysentery, such as Shigella spp. and Escherichia coli, which are very closely related if not identical species. Sensitive and precise detection and identification of the infectious agent is important to target the best therapeutic strategy, but the differential diagnosis of these two groups remains a challenge using conventional methods. Here, we present a nuclear magnetic resonance (NMR) based multivariate classification model employing bacterial metabolic footprints in postculture growth media with remarkable segregation capability, including the discrimination of lactose negative E. coli and Shigella spp. Our results confirm the potential of metabolomic markers in the field of bacterial identification for the distinction of even very closely related species.
Collapse
Affiliation(s)
- Gilles J. P. Rautureau
- Univ Lyon, CNRS, Université Claude Bernard Lyon 1, ENS de Lyon, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100 Villeurbanne, France
| | - Tony L. Palama
- Univ Lyon, CNRS, Université Claude Bernard Lyon 1, ENS de Lyon, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100 Villeurbanne, France
| | - Isabelle Canard
- bioMérieux, Innovation Unit—Microbiology Research, 38390 La Balme-les-Grottes, France
| | - Caroline Mirande
- bioMérieux, Innovation Unit—Microbiology Research, 38390 La Balme-les-Grottes, France
| | - Sonia Chatellier
- bioMérieux, Innovation Unit—Microbiology Research, 38390 La Balme-les-Grottes, France
| | - Alex van Belkum
- bioMérieux, Innovation Unit—Microbiology Research, 38390 La Balme-les-Grottes, France
| | - Bénédicte Elena-Herrmann
- Univ Lyon, CNRS, Université Claude Bernard Lyon 1, ENS de Lyon, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100 Villeurbanne, France
- Université Grenoble Alpes, CNRS, INSERM, IAB, Allée des Alpes, 38000 Grenoble, France
| |
Collapse
|
11
|
A comparative assessment of conventional and molecular methods, including MinION nanopore sequencing, for surveying water quality. Sci Rep 2019; 9:15726. [PMID: 31673047 PMCID: PMC6823499 DOI: 10.1038/s41598-019-51997-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 10/10/2019] [Indexed: 12/16/2022] Open
Abstract
Nucleic acid based techniques, such as quantitative PCR (qPCR) and next generation sequencing (NGS), provide new insights into microbial water quality, but considerable uncertainty remains around their correct interpretation. We demonstrate, for different water sources in informal settlements in the Kathmandu Valley, Nepal, significant Spearman rank correlations between conventional and molecular microbiology methods that indicate faecal contamination. At family and genera level, 16S rRNA amplicon sequencing results obtained with the low-cost, portable next generation sequencer MinION from Oxford Nanopore Technologies had significant Spearman rank correlations with Illumina MiSeq sequencing results. However, method validation by amplicon sequencing of a MOCK microbial community revealed the need to ascertain MinION sequencing results for putative pathogens at species level with complementary qPCR assays. Vibrio cholerae hazards were poorly associated with plate count faecal coliforms, but flagged up by the MinION screening method, and confirmed by a qPCR assay. Plate counting methods remain important to assess viability of faecal coliforms in disinfected water sources. We outline a systematic approach for data collection and interpretation of such complementary results. In the Kathmandu Valley, there is high variability of water quality from different sources, including for treated water samples, illustrating the importance of disinfection at the point of use.
Collapse
|
12
|
Acharya K, Khanal S, Pantha K, Amatya N, Davenport RJ, Werner D. A comparative assessment of conventional and molecular methods, including MinION nanopore sequencing, for surveying water quality. Sci Rep 2019. [PMID: 31673047 DOI: 10.1038/s41598-01951997-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
Abstract
Nucleic acid based techniques, such as quantitative PCR (qPCR) and next generation sequencing (NGS), provide new insights into microbial water quality, but considerable uncertainty remains around their correct interpretation. We demonstrate, for different water sources in informal settlements in the Kathmandu Valley, Nepal, significant Spearman rank correlations between conventional and molecular microbiology methods that indicate faecal contamination. At family and genera level, 16S rRNA amplicon sequencing results obtained with the low-cost, portable next generation sequencer MinION from Oxford Nanopore Technologies had significant Spearman rank correlations with Illumina MiSeq sequencing results. However, method validation by amplicon sequencing of a MOCK microbial community revealed the need to ascertain MinION sequencing results for putative pathogens at species level with complementary qPCR assays. Vibrio cholerae hazards were poorly associated with plate count faecal coliforms, but flagged up by the MinION screening method, and confirmed by a qPCR assay. Plate counting methods remain important to assess viability of faecal coliforms in disinfected water sources. We outline a systematic approach for data collection and interpretation of such complementary results. In the Kathmandu Valley, there is high variability of water quality from different sources, including for treated water samples, illustrating the importance of disinfection at the point of use.
Collapse
Affiliation(s)
- Kishor Acharya
- School of Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom
| | - Santosh Khanal
- Department of Pharmacology, School of Medicine, University of Colorado, Aurora, Colorado, 80045, USA
| | - Kalyan Pantha
- Group for Rural Infrastructure Development, Wise use House, Jwagal, Lalitpur, Nepal
- Faculty of Chemistry, University Duisburg-Essen, Universitätsstr. 5, D-45141, Essen, Germany
| | - Niroj Amatya
- Faculty of Chemistry, University Duisburg-Essen, Universitätsstr. 5, D-45141, Essen, Germany
- Department of Medical Microbiology, Nobel College, Pokhara University, Kathmandu, Nepal
| | - Russell J Davenport
- School of Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom
| | - David Werner
- School of Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom.
| |
Collapse
|
13
|
Van Boeckel TP, Pires J, Silvester R, Zhao C, Song J, Criscuolo NG, Gilbert M, Bonhoeffer S, Laxminarayan R. Global trends in antimicrobial resistance in animals in low- and middle-income countries. Science 2019; 365:365/6459/eaaw1944. [DOI: 10.1126/science.aaw1944] [Citation(s) in RCA: 369] [Impact Index Per Article: 73.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/19/2019] [Accepted: 07/31/2019] [Indexed: 12/17/2022]
Abstract
The global scale-up in demand for animal protein is the most notable dietary trend of our time. Antimicrobial consumption in animals is threefold that of humans and has enabled large-scale animal protein production. The consequences for the development of antimicrobial resistance in animals have received comparatively less attention than in humans. We analyzed 901 point prevalence surveys of pathogens in developing countries to map resistance in animals. China and India represented the largest hotspots of resistance, with new hotspots emerging in Brazil and Kenya. From 2000 to 2018, the proportion of antimicrobials showing resistance above 50% increased from 0.15 to 0.41 in chickens and from 0.13 to 0.34 in pigs. Escalating resistance in animals is anticipated to have important consequences for animal health and, eventually, for human health.
Collapse
|
14
|
Mark Welch JL, Dewhirst FE, Borisy GG. Biogeography of the Oral Microbiome: The Site-Specialist Hypothesis. Annu Rev Microbiol 2019; 73:335-358. [PMID: 31180804 PMCID: PMC7153577 DOI: 10.1146/annurev-micro-090817-062503] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Microbial communities are complex and dynamic, composed of hundreds of taxa interacting across multiple spatial scales. Advances in sequencing and imaging technology have led to great strides in understanding both the composition and the spatial organization of these complex communities. In the human mouth, sequencing results indicate that distinct sites host microbial communities that not only are distinguishable but to a meaningful degree are composed of entirely different microbes. Imaging suggests that the spatial organization of these communities is also distinct. Together, the literature supports the idea that most oral microbes are site specialists. A clear understanding of microbiota structure at different sites in the mouth enables mechanistic studies, informs the generation of hypotheses, and strengthens the position of oral microbiology as a model system for microbial ecology in general.
Collapse
Affiliation(s)
| | - Floyd E. Dewhirst
- The Forsyth Institute, Cambridge MA 02142 and Harvard School of Dental Medicine, Boston MA 02115
| | | |
Collapse
|
15
|
Thompson DW, Casjens SR, Sharma R, Grose JH. Genomic comparison of 60 completely sequenced bacteriophages that infect Erwinia and/or Pantoea bacteria. Virology 2019; 535:59-73. [PMID: 31276862 DOI: 10.1016/j.virol.2019.06.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 12/15/2022]
Abstract
Erwinia and Pantoea are closely related bacterial plant pathogens in the Gram negative Enterobacteriales order. Sixty tailed bacteriophages capable of infecting these pathogens have been completely sequenced by investigators around the world and are in the current databases, 30 of which were sequenced by our lab. These 60 were compared to 991 other Enterobacteriales bacteriophage genomes and found to be, on average, just over twice the overall average length. These Erwinia and Pantoea phages comprise 20 clusters based on nucleotide and protein sequences. Five clusters contain only phages that infect the Erwinia and Pantoea genera, the other 15 clusters are closely related to bacteriophages that infect other Enterobacteriales; however, within these clusters the Erwinia and Pantoea phages tend to be distinct, suggesting ecological niche may play a diversification role. The failure of many of their encoded proteins to have predicted functions highlights the need for further study of these phages.
Collapse
Affiliation(s)
- Daniel W Thompson
- Department of Microbiology and Molecular Biology, Brigham Young University, Utah, USA
| | - Sherwood R Casjens
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, University of Utah, Salt Lake City, UT, 84112, USA; School of Biological Sciences, University of Utah, Salt Lake City, UT, 84112, USA
| | - Ruchira Sharma
- Department of Microbiology and Molecular Biology, Brigham Young University, Utah, USA
| | - Julianne H Grose
- Department of Microbiology and Molecular Biology, Brigham Young University, Utah, USA.
| |
Collapse
|
16
|
Hayashi Sant’Anna F, Bach E, Porto RZ, Guella F, Hayashi Sant’Anna E, Passaglia LMP. Genomic metrics made easy: what to do and where to go in the new era of bacterial taxonomy. Crit Rev Microbiol 2019; 45:182-200. [DOI: 10.1080/1040841x.2019.1569587] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Fernando Hayashi Sant’Anna
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Evelise Bach
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Renan Z. Porto
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Felipe Guella
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Eduardo Hayashi Sant’Anna
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Luciane M. P. Passaglia
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| |
Collapse
|
17
|
Mirsepasi-Lauridsen HC, Vallance BA, Krogfelt KA, Petersen AM. Escherichia coli Pathobionts Associated with Inflammatory Bowel Disease. Clin Microbiol Rev 2019; 32:e00060-18. [PMID: 30700431 PMCID: PMC6431131 DOI: 10.1128/cmr.00060-18] [Citation(s) in RCA: 163] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Gut bacteria play a key role in initiating and maintaining the inflammatory process in the gut tissues of inflammatory bowel disease (IBD) patients, by supplying antigens or other stimulatory factors that trigger immune cell activation. Changes in the composition of the intestinal microbiota in IBD patients compared to that in healthy controls and a reduced diversity of intestinal microbial species are linked to the pathogenesis of IBD. Adherent invasive Escherichia coli (AIEC) has been linked to Crohn's disease (CD) patients, while diffusely adherent E. coli (DAEC) has been associated with ulcerative colitis (UC). Bacteriological analysis of intestinal biopsy specimens and fecal samples from IBD patients shows an increased number of E. coli strains belonging to the B2 phylogenetic group, which are typically known as extraintestinal pathogenic E. coli (ExPEC). Results from studies of both cell cultures and animal models reveal pathogenic features of these E. coli pathobionts, which may link them to IBD pathogenesis. This suggests that IBD-associated E. coli strains play a facilitative role during IBD flares. In this review, we explain IBD-associated E. coli and its role in IBD pathogenesis.
Collapse
Affiliation(s)
| | - Bruce Andrew Vallance
- Division of Gastroenterology, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Karen Angeliki Krogfelt
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
- Department of Viral and Microbiological Diagnostics, Statens Serum Institut, Copenhagen, Denmark
| | - Andreas Munk Petersen
- Department of Gastroenterology, Hvidovre University Hospital, Copenhagen, Denmark
- Department of Clinical Microbiology, Hvidovre University Hospital, Copenhagen, Denmark
| |
Collapse
|
18
|
Cattonaro F, Spadotto A, Radovic S, Marroni F. Do you cov me? Effect of coverage reduction on metagenome shotgun sequencing studies. F1000Res 2018; 7:1767. [PMID: 32185014 PMCID: PMC7059852 DOI: 10.12688/f1000research.16804.4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/15/2020] [Indexed: 01/16/2023] Open
Abstract
Shotgun metagenomics sequencing is a powerful tool for the characterization of complex biological matrices, enabling analysis of prokaryotic and eukaryotic organisms and viruses in a single experiment, with the possibility of reconstructing
de novo the whole metagenome or a set of genes of interest. One of the main factors limiting the use of shotgun metagenomics on wide scale projects is the high cost associated with the approach. We set out to determine if it is possible to use shallow shotgun metagenomics to characterize complex biological matrices while reducing costs. We used a staggered mock community to estimate the optimal threshold for species detection. We measured the variation of several summary statistics simulating a decrease in sequencing depth by randomly subsampling a number of reads. The main statistics that were compared are diversity estimates, species abundance, and ability of reconstructing
de novo the metagenome in terms of length and completeness. Our results show that diversity indices of complex prokaryotic, eukaryotic and viral communities can be accurately estimated with 500,000 reads or less, although particularly complex samples may require 1,000,000 reads. On the contrary, any task involving the reconstruction of the metagenome performed poorly, even with the largest simulated subsample (1,000,000 reads). The length of the reconstructed assembly was smaller than the length obtained with the full dataset, and the proportion of conserved genes that were identified in the meta-genome was drastically reduced compared to the full sample. Shallow shotgun metagenomics can be a useful tool to describe the structure of complex matrices, but it is not adequate to reconstruct—even partially—the metagenome.
Collapse
Affiliation(s)
| | | | | | - Fabio Marroni
- IGA Technology Services Srl, Udine, Udine, 33100, Italy.,Department of Agricultural, Food, Environmental and Animal Sciences (DI4A), University of Udine, Udine, 33100, Italy
| |
Collapse
|
19
|
Abrahams L, Hurst LD. Adenine Enrichment at the Fourth CDS Residue in Bacterial Genes Is Consistent with Error Proofing for +1 Frameshifts. Mol Biol Evol 2018; 34:3064-3080. [PMID: 28961919 PMCID: PMC5850271 DOI: 10.1093/molbev/msx223] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Beyond selection for optimal protein functioning, coding sequences (CDSs) are under selection at the RNA and DNA levels. Here, we identify a possible signature of “dual-coding,” namely extensive adenine (A) enrichment at bacterial CDS fourth sites. In 99.07% of studied bacterial genomes, fourth site A use is greater than expected given genomic A-starting codon use. Arguing for nucleotide level selection, A-starting serine and arginine second codons are heavily utilized when compared with their non-A starting synonyms. Several models have the ability to explain some of this trend. In part, A-enrichment likely reduces 5′ mRNA stability, promoting translation initiation. However T/U, which may also reduce stability, is avoided. Further, +1 frameshifts on the initiating ATG encode a stop codon (TGA) provided A is the fourth residue, acting either as a frameshift “catch and destroy” or a frameshift stop and adjust mechanism and hence implicated in translation initiation. Consistent with both, genomes lacking TGA stop codons exhibit weaker fourth site A-enrichment. Sequences lacking a Shine–Dalgarno sequence and those without upstream leader genes, that may be more error prone during initiation, have greater utilization of A, again suggesting a role in initiation. The frameshift correction model is consistent with the notion that many genomic features are error-mitigation factors and provides the first evidence for site-specific out of frame stop codon selection. We conjecture that the NTG universal start codon may have evolved as a consequence of TGA being a stop codon and the ability of NTGA to rapidly terminate or adjust a ribosome.
Collapse
Affiliation(s)
- Liam Abrahams
- Department of Biology and Biochemistry, The Milner Centre for Evolution, University of Bath, Bath, United Kingdom
| | - Laurence D Hurst
- Department of Biology and Biochemistry, The Milner Centre for Evolution, University of Bath, Bath, United Kingdom
| |
Collapse
|
20
|
Cowley LA, Oresegun DR, Chattaway MA, Dallman TJ, Jenkins C. Phylogenetic comparison of enteroinvasive Escherichia coli isolated from cases of diarrhoeal disease in England, 2005-2016. J Med Microbiol 2018; 67:884-888. [PMID: 29693541 DOI: 10.1099/jmm.0.000739] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We compared the genomes of 60 isolates of enteroinvasive Escherichia coli (EIEC) in order to better understand the step-wise evolutionary process from non-pathogenic to host-adapted pathogenic E. coli. All isolates belonged to either sequence type (ST) 6, ST99 or ST270. Each ST was located on different branches of the E. coli phylogeny and had invasion plasmids (pINVs) belonging to FII-21 (ST99, ST270), FII-27 (ST270) or FII-28 (ST6, ST270) incompatibility groups. A higher number of insertion sequence (IS) elements were identified in ST6 and ST270 than in ST99, and appeared to be driving the loss of functional genes. Comparison of the pINV from each ST revealed different degrees of gene loss, with pINV from ST270 being most similar to that found in Shigella species. We captured three EIEC STs at different stages of patho-adaptation, with ST270 being the most 'shigella-like' and the most divergent from non-pathogenic E. coli, and ST99 being the least divergent.
Collapse
Affiliation(s)
- Lauren A Cowley
- Gastrointestinal Bacteria Reference Unit, Public Health England, Colindale, London, UK
| | - Damilola R Oresegun
- Gastrointestinal Bacteria Reference Unit, Public Health England, Colindale, London, UK.,School of Life and Medical Sciences, University of Hertfordshire, Hatfield, Hertfordshire, UK
| | - Marie A Chattaway
- Gastrointestinal Bacteria Reference Unit, Public Health England, Colindale, London, UK
| | - Timothy J Dallman
- Gastrointestinal Bacteria Reference Unit, Public Health England, Colindale, London, UK
| | - Claire Jenkins
- Gastrointestinal Bacteria Reference Unit, Public Health England, Colindale, London, UK
| |
Collapse
|
21
|
Schaeffer L, Pimentel H, Bray N, Melsted P, Pachter L. Pseudoalignment for metagenomic read assignment. Bioinformatics 2018; 33:2082-2088. [PMID: 28334086 DOI: 10.1093/bioinformatics/btx106] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 02/17/2017] [Indexed: 12/13/2022] Open
Abstract
Motivation Read assignment is an important first step in many metagenomic analysis workflows, providing the basis for identification and quantification of species. However ambiguity among the sequences of many strains makes it difficult to assign reads at the lowest level of taxonomy, and reads are typically assigned to taxonomic levels where they are unambiguous. We explore connections between metagenomic read assignment and the quantification of transcripts from RNA-Seq data in order to develop novel methods for rapid and accurate quantification of metagenomic strains. Results We find that the recent idea of pseudoalignment introduced in the RNA-Seq context is highly applicable in the metagenomics setting. When coupled with the Expectation-Maximization (EM) algorithm, reads can be assigned far more accurately and quickly than is currently possible with state of the art software, making it possible and practical for the first time to analyze abundances of individual genomes in metagenomics projects. Availability and Implementation Pipeline and analysis code can be downloaded from http://github.com/pachterlab/metakallisto. Contact lpachter@math.berkeley.edu.
Collapse
Affiliation(s)
- L Schaeffer
- Department of Molecular and Cell Biology, UC Berkeley, Berkeley, CA, USA
| | - H Pimentel
- Department of Genetics, Stanford University, Stanford, CA, USA
| | - N Bray
- Department of Molecular and Cell Biology and Innovative Genomics Institute, UC Berkeley, Berkeley, CA, USA
| | - P Melsted
- Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, University of Iceland, Reykjavik, Iceland
| | - L Pachter
- Department of Molecular and Cell Biology, UC Berkeley, Berkeley, CA, USA.,Departments of Mathematics and Computer Science, UC Berkeley, Berkeley, CA, USA
| |
Collapse
|
22
|
Pedersen TL. Hierarchical sets: analyzing pangenome structure through scalable set visualizations. Bioinformatics 2018; 33:1604-1612. [PMID: 28130242 PMCID: PMC5447240 DOI: 10.1093/bioinformatics/btx034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 01/24/2017] [Indexed: 12/13/2022] Open
Abstract
Motivation The increase in available microbial genome sequences has resulted in an increase in the size of the pangenomes being analyzed. Current pangenome visualizations are not intended for the pangenome sizes possible today and new approaches are necessary in order to convert the increase in available information to increase in knowledge. As the pangenome data structure is essentially a collection of sets we explore the potential for scalable set visualization as a tool for pangenome analysis. Results We present a new hierarchical clustering algorithm based on set arithmetics that optimizes the intersection sizes along the branches. The intersection and union sizes along the hierarchy are visualized using a composite dendrogram and icicle plot, which, in pangenome context, shows the evolution of pangenome and core size along the evolutionary hierarchy. Outlying elements, i.e. elements whose presence pattern do not correspond with the hierarchy, can be visualized using hierarchical edge bundles. When applied to pangenome data this plot shows putative horizontal gene transfers between the genomes and can highlight relationships between genomes that is not represented by the hierarchy. We illustrate the utility of hierarchical sets by applying it to a pangenome based on 113 Escherichia and Shigella genomes and find it provides a powerful addition to pangenome analysis. Availability and Implementation The described clustering algorithm and visualizations are implemented in the hierarchicalSets R package available from CRAN (https://cran.r-project.org/web/packages/hierarchicalSets) Supplementary information Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Thomas Lin Pedersen
- Department of Systems Biology, Center for Biological Sequence Analysis, The Technical University of Denmark, Building 208, Lyngby, Denmark.,Assays, Culture and Enzymes Division, Chr. Hansen A/S, Hørsholm, Denmark
| |
Collapse
|
23
|
Massucci FA, Sagués F, Serrano MÁ. Metabolic plasticity in synthetic lethal mutants: Viability at higher cost. PLoS Comput Biol 2018; 14:e1005949. [PMID: 29381693 PMCID: PMC5806928 DOI: 10.1371/journal.pcbi.1005949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 02/09/2018] [Accepted: 12/29/2017] [Indexed: 12/15/2022] Open
Abstract
The most frequent form of pairwise synthetic lethality (SL) in metabolic networks is known as plasticity synthetic lethality. It occurs when the simultaneous inhibition of paired functional and silent metabolic reactions or genes is lethal, while the default of the functional partner is backed up by the activation of the silent one. Using computational techniques on bacterial genome-scale metabolic reconstructions, we found that the failure of the functional partner triggers a critical reorganization of fluxes to ensure viability in the mutant which not only affects the SL pair but a significant fraction of other interconnected reactions, forming what we call a SL cluster. Interestingly, SL clusters show a strong entanglement both in terms of reactions and genes. This strong overlap mitigates the acquired vulnerabilities and increased structural and functional costs that pay for the robustness provided by essential plasticity. Finally, the participation of coessential reactions and genes in different SL clusters is very heterogeneous and those at the intersection of many SL clusters could serve as supertargets for more efficient drug action in the treatment of complex diseases and to elucidate improved strategies directed to reduce undesired resistance to chemicals in pathogens.
Collapse
Affiliation(s)
| | - Francesc Sagués
- Departament de Química Física, Universitat de Barcelona, Martí i Franquès 1, Barcelona, Spain
| | - M. Ángeles Serrano
- Departament de Física de la Matèria Condensada, Universitat de Barcelona, Martí i Franquès 1, Barcelona, Spain
- Universitat de Barcelona Institute of Complex Systems (UBICS), Universitat de Barcelona, Barcelona, Spain
- ICREA, Pg. Lluís Companys 23, Barcelona, Spain
- * E-mail:
| |
Collapse
|
24
|
Pasqua M, Michelacci V, Di Martino ML, Tozzoli R, Grossi M, Colonna B, Morabito S, Prosseda G. The Intriguing Evolutionary Journey of Enteroinvasive E. coli (EIEC) toward Pathogenicity. Front Microbiol 2017; 8:2390. [PMID: 29259590 PMCID: PMC5723341 DOI: 10.3389/fmicb.2017.02390] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/20/2017] [Indexed: 01/01/2023] Open
Abstract
Among the intestinal pathogenic Escherichia coli, enteroinvasive E. coli (EIEC) are a group of intracellular pathogens able to enter epithelial cells of colon, multiplicate within them, and move between adjacent cells with a mechanism similar to Shigella, the ethiological agent of bacillary dysentery. Despite EIEC belong to the same pathotype of Shigella, they neither have the full set of traits that define Shigella nor have undergone the extensive gene decay observed in Shigella. Molecular analysis confirms that EIEC are widely distributed among E. coli phylogenetic groups and correspond to bioserotypes found in many E. coli serogroups. Like Shigella, also in EIEC the critical event toward a pathogenic life-style consisted in the acquisition by horizontal gene transfer of a large F-type plasmid (pINV) containing the genes required for invasion, intracellular survival, and spreading through the intestinal mucosa. In Shigella, the ample gain in virulence determinants has been counteracted by a substantial loss of functions that, although important for the survival in the environment, are redundant or deleterious for the life inside the host. The pathoadaptation process that has led Shigella to modify its metabolic profile and increase its pathogenic potential is still in infancy in EIEC, although maintenance of some features typical of E. coli might favor their emerging relevance as intestinal pathogens worldwide, as documented by recent outbreaks in industrialized countries. In this review, we will discuss the evolution of EIEC toward Shigella-like invasive forms going through the epidemiology, including the emergence of new virulent strains, their genome organization, and the complex interactions they establish with the host.
Collapse
Affiliation(s)
- Martina Pasqua
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Valeria Michelacci
- European Union Reference Laboratory for Escherichia coli, Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Maria Letizia Di Martino
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Rosangela Tozzoli
- European Union Reference Laboratory for Escherichia coli, Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Milena Grossi
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Bianca Colonna
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Stefano Morabito
- European Union Reference Laboratory for Escherichia coli, Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Gianni Prosseda
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| |
Collapse
|
25
|
Hugerth LW, Andersson AF. Analysing Microbial Community Composition through Amplicon Sequencing: From Sampling to Hypothesis Testing. Front Microbiol 2017; 8:1561. [PMID: 28928718 PMCID: PMC5591341 DOI: 10.3389/fmicb.2017.01561] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Accepted: 08/02/2017] [Indexed: 12/20/2022] Open
Abstract
Microbial ecology as a scientific field is fundamentally driven by technological advance. The past decade's revolution in DNA sequencing cost and throughput has made it possible for most research groups to map microbial community composition in environments of interest. However, the computational and statistical methodology required to analyse this kind of data is often not part of the biologist training. In this review, we give a historical perspective on the use of sequencing data in microbial ecology and restate the current need for this method; but also highlight the major caveats with standard practices for handling these data, from sample collection and library preparation to statistical analysis. Further, we outline the main new analytical tools that have been developed in the past few years to bypass these caveats, as well as highlight the major requirements of common statistical practices and the extent to which they are applicable to microbial data. Besides delving into the meaning of select alpha- and beta-diversity measures, we give special consideration to techniques for finding the main drivers of community dissimilarity and for interaction network construction. While every project design has specific needs, this review should serve as a starting point for considering what options are available.
Collapse
Affiliation(s)
- Luisa W Hugerth
- Department of Molecular, Tumour and Cell Biology, Centre for Translational Microbiome Research, Karolinska InstitutetSolna, Sweden.,Division of Gene Technology, Science for Life Laboratory, School of Biotechnology, KTH Royal Institute of TechnologySolna, Sweden
| | - Anders F Andersson
- Division of Gene Technology, Science for Life Laboratory, School of Biotechnology, KTH Royal Institute of TechnologySolna, Sweden
| |
Collapse
|
26
|
Gene content dissimilarity for subclassification of highly similar microbial strains. BMC Genomics 2016; 17:647. [PMID: 27530250 PMCID: PMC4988056 DOI: 10.1186/s12864-016-2991-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 08/03/2016] [Indexed: 11/23/2022] Open
Abstract
Background Identification and classification of highly similar microbial strains is a challenging issue in microbiology, ecology and evolutionary biology. Among various available approaches, gene content analysis is also at the core of microbial taxonomy. However, no threshold has been determined for grouping microorgnisms to different taxonomic levels, and it is still not clear that to what extent genomic fluidity should occur to form a microbial taxonomic group. Results By taking advantage of the eggNOG database for orthologous groups, we calculated gene content dissimilarity among different microbial strains based on the orthologous gene profiles and tested the possibility of applying gene content dissimilarity as a quantitative index in classifying microbial taxonomic groups, as well as its potential application in subclassification of highly similar microbial strains. Evaluation of gene content dissimilarity to completed microbial genomes at different taxonomic levels suggested that cutoffs of 0.2 and 0.4 can be respectively used for species and family delineation, and that 0.2 gene content dissimilarity cutoff approximately corresponded to 98 % 16S rRNA gene identity and 94 % ANI for microbial species delineation. Furthermore, application of gene content dissimilarity to highly similar microbial strains suggested it as an effective approach in classifying closely related microorganisms into subgroups. Conclusions This approach is especially useful in identifying pathogens from commensals in clinical microbiology. It also provides novel insights into how genomic fluidity is linked with microbial taxonomy. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2991-9) contains supplementary material, which is available to authorized users.
Collapse
|
27
|
Pettengill EA, Pettengill JB, Binet R. Phylogenetic Analyses of Shigella and Enteroinvasive Escherichia coli for the Identification of Molecular Epidemiological Markers: Whole-Genome Comparative Analysis Does Not Support Distinct Genera Designation. Front Microbiol 2016; 6:1573. [PMID: 26834722 PMCID: PMC4718091 DOI: 10.3389/fmicb.2015.01573] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 12/28/2015] [Indexed: 12/30/2022] Open
Abstract
As a leading cause of bacterial dysentery, Shigella represents a significant threat to public health and food safety. Related, but often overlooked, enteroinvasive Escherichia coli (EIEC) can also cause dysentery. Current typing methods have limited ability to identify and differentiate between these pathogens despite the need for rapid and accurate identification of pathogens for clinical treatment and outbreak response. We present a comprehensive phylogeny of Shigella and EIEC using whole genome sequencing of 169 samples, constituting unparalleled strain diversity, and observe a lack of monophyly between Shigella and EIEC and among Shigella taxonomic groups. The evolutionary relationships in the phylogeny are supported by analyses of population structure and hierarchical clustering patterns of translated gene homolog abundance. Lastly, we identified a panel of 254 single nucleotide polymorphism (SNP) markers specific to each phylogenetic cluster for more accurate identification of Shigella and EIEC. Our findings show that Shigella and EIEC are not distinct evolutionary groups within the E. coli genus and, thus, EIEC as a group is not the ancestor to Shigella. The multiple analyses presented provide evidence for reconsidering the taxonomic placement of Shigella. The SNP markers offer more discriminatory power to molecular epidemiological typing methods involving these bacterial pathogens.
Collapse
Affiliation(s)
- Emily A Pettengill
- Division of Microbiology, Office of Regulatory Science, U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition College Park, MD, USA
| | - James B Pettengill
- Division of Public Health Informatics and Analytics, Office of Analytics and Outreach, U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition College Park, MD, USA
| | - Rachel Binet
- Division of Microbiology, Office of Regulatory Science, U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition College Park, MD, USA
| |
Collapse
|
28
|
What Can We Learn from a Metagenomic Analysis of a Georgian Bacteriophage Cocktail? Viruses 2015; 7:6570-89. [PMID: 26703713 PMCID: PMC4690881 DOI: 10.3390/v7122958] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/19/2015] [Accepted: 11/30/2015] [Indexed: 01/21/2023] Open
Abstract
Phage therapy, a practice widespread in Eastern Europe, has untapped potential in the combat against antibiotic-resistant bacterial infections. However, technology transfer to Western medicine is proving challenging. Bioinformatics analysis could help to facilitate this endeavor. In the present study, the Intesti phage cocktail, a key commercial product of the Eliava Institute, Georgia, has been tested on a selection of bacterial strains, sequenced as a metagenomic sample, de novo assembled and analyzed by bioinformatics methods. Furthermore, eight bacterial host strains were infected with the cocktail and the resulting lysates sequenced and compared to the unamplified cocktail. The analysis identified 23 major phage clusters in different abundances in the cocktail, among those clusters related to the ICTV genera T4likevirus, T5likevirus, T7likevirus, Chilikevirus and Twortlikevirus, as well as a cluster that was quite distant to the database sequences and a novel Proteus phage cluster. Examination of the depth of coverage showed the clusters to have different abundances within the cocktail. The cocktail was found to be composed primarily of Myoviridae (35%) and Siphoviridae (32%), with Podoviridae being a minority (15%). No undesirable genes were found.
Collapse
|
29
|
Zuo G, Hao B. CVTree3 Web Server for Whole-genome-based and Alignment-free Prokaryotic Phylogeny and Taxonomy. GENOMICS, PROTEOMICS & BIOINFORMATICS 2015; 13:321-31. [PMID: 26563468 PMCID: PMC4678791 DOI: 10.1016/j.gpb.2015.08.004] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 08/10/2015] [Indexed: 01/15/2023]
Abstract
A faithful phylogeny and an objective taxonomy for prokaryotes should agree with each other and ultimately follow the genome data. With the number of sequenced genomes reaching tens of thousands, both tree inference and detailed comparison with taxonomy are great challenges. We now provide one solution in the latest Release 3.0 of the alignment-free and whole-genome-based web server CVTree3. The server resides in a cluster of 64 cores and is equipped with an interactive, collapsible, and expandable tree display. It is capable of comparing the tree branching order with prokaryotic classification at all taxonomic ranks from domains down to species and strains. CVTree3 allows for inquiry by taxon names and trial on lineage modifications. In addition, it reports a summary of monophyletic and non-monophyletic taxa at all ranks as well as produces print-quality subtree figures. After giving an overview of retrospective verification of the CVTree approach, the power of the new server is described for the mega-classification of prokaryotes and determination of taxonomic placement of some newly-sequenced genomes. A few discrepancies between CVTree and 16S rRNA analyses are also summarized with regard to possible taxonomic revisions. CVTree3 is freely accessible to all users at http://tlife.fudan.edu.cn/cvtree3/ without login requirements.
Collapse
Affiliation(s)
- Guanghong Zuo
- T-Life Research Center, Department of Physics, Fudan University, Shanghai 200433, China
| | - Bailin Hao
- T-Life Research Center, Department of Physics, Fudan University, Shanghai 200433, China.
| |
Collapse
|
30
|
Mendes Silva D, Domingues L. On the track for an efficient detection of Escherichia coli in water: A review on PCR-based methods. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2015; 113:400-11. [PMID: 25540852 DOI: 10.1016/j.ecoenv.2014.12.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 12/03/2014] [Accepted: 12/08/2014] [Indexed: 05/11/2023]
Abstract
Ensuring water safety is an ongoing challenge to public health providers. Assessing the presence of fecal contamination indicators in water is essential to protect public health from diseases caused by waterborne pathogens. For this purpose, the bacteria Escherichia coli has been used as the most reliable indicator of fecal contamination in water. The methods currently in use for monitoring the microbiological safety of water are based on culturing the microorganisms. However, these methods are not the desirable solution to prevent outbreaks as they provide the results with a considerable delay, lacking on specificity and sensitivity. Moreover, viable but non-culturable microorganisms, which may be present as a result of environmental stress or water treatment processes, are not detected by culture-based methods and, thus, may result in false-negative assessments of E. coli in water samples. These limitations may place public health at significant risk, leading to substantial monetary losses in health care and, additionally, in costs related with a reduced productivity in the area affected by the outbreak, and in costs supported by the water quality control departments involved. Molecular methods, particularly polymerase chain reaction-based methods, have been studied as an alternative technology to overcome the current limitations, as they offer the possibility to reduce the assay time, to improve the detection sensitivity and specificity, and to identify multiple targets and pathogens, including new or emerging strains. The variety of techniques and applications available for PCR-based methods has increased considerably and the costs involved have been substantially reduced, which together have contributed to the potential standardization of these techniques. However, they still require further refinement in order to be standardized and applied to the variety of environmental waters and their specific characteristics. The PCR-based methods under development for monitoring the presence of E. coli in water are here discussed. Special emphasis is given to methodologies that avoid pre-enrichment during the water sample preparation process so that the assay time is reduced and the required legislated sensitivity is achieved. The advantages and limitations of these methods are also reviewed, contributing to a more comprehensive overview toward a more conscious research in identifying E. coli in water.
Collapse
Affiliation(s)
- Diana Mendes Silva
- CEB-Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.
| | - Lucília Domingues
- CEB-Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.
| |
Collapse
|
31
|
Abstract
PURPOSE OF REVIEW Shigella spp. are important etiologic agents of diarrhea worldwide. This review summarizes the recent findings on the epidemiology, diagnosis, virulence genes, and pathobiology of Shigella infection. RECENT FINDINGS Shigella flexneri and Shigella sonnei have been identified as the main serogroups circulating in developing and developed countries, respectively. However, a shift in the dominant species from S. flexneri to S. sonnei has been observed in countries that have experienced recent improvements in socioeconomic conditions. Despite the increasing usage of molecular methods in the diagnosis and virulence characterization of Shigella strains, researchers have been unsuccessful in finding a specific target gene for this bacillus. New research has demonstrated the role of proteins whose expressions are temperature-regulated, as well as genes involved in the processes of adhesion, invasion, dissemination, and inflammation, aiding in the clarification of the complex pathobiology of shigellosis. SUMMARY Knowledge about the epidemiologic profile of circulating serogroups of Shigella and an understanding of its pathobiology as well as of the virulence genes is important for the development of preventive measures and interventions to reduce the worldwide spread of shigellosis.
Collapse
|
32
|
Meier-Kolthoff JP, Hahnke RL, Petersen J, Scheuner C, Michael V, Fiebig A, Rohde C, Rohde M, Fartmann B, Goodwin LA, Chertkov O, Reddy TBK, Pati A, Ivanova NN, Markowitz V, Kyrpides NC, Woyke T, Göker M, Klenk HP. Complete genome sequence of DSM 30083(T), the type strain (U5/41(T)) of Escherichia coli, and a proposal for delineating subspecies in microbial taxonomy. Stand Genomic Sci 2014; 9:2. [PMID: 25780495 PMCID: PMC4334874 DOI: 10.1186/1944-3277-9-2] [Citation(s) in RCA: 353] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 06/16/2014] [Indexed: 12/02/2022] Open
Abstract
Although Escherichia coli is the most widely studied bacterial model organism and often considered to be the model bacterium per se, its type strain was until now forgotten from microbial genomics. As a part of the G enomic E ncyclopedia of B acteria and A rchaea project, we here describe the features of E. coli DSM 30083(T) together with its genome sequence and annotation as well as novel aspects of its phenotype. The 5,038,133 bp containing genome sequence includes 4,762 protein-coding genes and 175 RNA genes as well as a single plasmid. Affiliation of a set of 250 genome-sequenced E. coli strains, Shigella and outgroup strains to the type strain of E. coli was investigated using digital DNA:DNA-hybridization (dDDH) similarities and differences in genomic G+C content. As in the majority of previous studies, results show Shigella spp. embedded within E. coli and in most cases forming a single subgroup of it. Phylogenomic trees also recover the proposed E. coli phylotypes as monophyla with minor exceptions and place DSM 30083(T) in phylotype B2 with E. coli S88 as its closest neighbor. The widely used lab strain K-12 is not only genomically but also physiologically strongly different from the type strain. The phylotypes do not express a uniform level of character divergence as measured using dDDH, however, thus an alternative arrangement is proposed and discussed in the context of bacterial subspecies. Analyses of the genome sequences of a large number of E. coli strains and of strains from > 100 other bacterial genera indicate a value of 79-80% dDDH as the most promising threshold for delineating subspecies, which in turn suggests the presence of five subspecies within E. coli.
Collapse
Affiliation(s)
- Jan P Meier-Kolthoff
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Richard L Hahnke
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Jörn Petersen
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Carmen Scheuner
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Victoria Michael
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Anne Fiebig
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Christine Rohde
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Manfred Rohde
- />Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | | | | | | | - TBK Reddy
- />DOE Joint Genome Institute, Walnut Creek, Ca USA
| | - Amrita Pati
- />DOE Joint Genome Institute, Walnut Creek, Ca USA
| | | | | | - Nikos C Kyrpides
- />DOE Joint Genome Institute, Walnut Creek, Ca USA
- />Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Tanja Woyke
- />DOE Joint Genome Institute, Walnut Creek, Ca USA
| | - Markus Göker
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Hans-Peter Klenk
- />Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| |
Collapse
|
33
|
Zuo G, Li Q, Hao B. On K-peptide length in composition vector phylogeny of prokaryotes. Comput Biol Chem 2014; 53 Pt A:166-73. [PMID: 25205031 DOI: 10.1016/j.compbiolchem.2014.08.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/11/2014] [Indexed: 11/25/2022]
Abstract
Using an enlarged alphabet of K-tuples is the way to carry out alignment-free comparison of genomes in the composition vector (CV) approach to prokaryotic phylogeny. We summarize the known aspects concerning the choice of K and examine the results of using CVs with subtraction of a statistical background for K=3-9 and using raw CVs without subtraction for K=1-12. The criterion for evaluation consists in direct comparison with taxonomy. For prokaryotes the best performances are obtained for K=5 and 6 with subtraction and for K=11, 12 or even more without subtraction. In general, CVs with subtractions are slightly better and less CPU consuming, but CVs without subtraction may provide complementary information.
Collapse
Affiliation(s)
- Guanghong Zuo
- T-Life Research Center, Fudan University, Shanghai 200433, China
| | - Qiang Li
- CAS-MPG Partner Institute for Computational Biology, Shanghai 200032, China
| | - Bailin Hao
- T-Life Research Center, Fudan University, Shanghai 200433, China.
| |
Collapse
|