scholarly journals Re-identification of strains deposited as Pseudomonas aeruginosa, Pseudomonas fluorescens and Pseudomonas putida in GenBank based on whole genome sequences

2020 ◽  
Vol 70 (11) ◽  
pp. 5958-5963
Author(s):  
Yuh Morimoto ◽  
Mari Tohya ◽  
Zulipiya Aibibula ◽  
Tadashi Baba ◽  
Hiroyuki Daida ◽  
...  

The taxonomic classification of Pseudomonas species has been revised and updated several times. This study utilized average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) cutoff values of 95 and 70 %, respectively, to re-identify the species of strains deposited in GenBank as P. aeruginosa , P. fluorescens and P. putida . Of the 264 deposited P. aeruginosa strains, 259 were correctly identified as P. aeruginosa , but the remaining five were not. All 28 deposited P. fluorescens strains had been incorrectly identified as P. fluorescens . Four of these strains were re-identified, including two as P. kilonensis and one each as P. aeruginosa and P. brassicacearum , but the remaining 24 could not be re-identified. Similarly, all 35 deposited P. putida strains had been incorrectly identified as P. putida . Nineteen of these strains were re-identified, including 12 as P. alloputida , four as P. asiatica and one each as P. juntendi , P. monteilii and P. mosselii . These results strongly suggest that Pseudomonas bacteria should be identified using ANI and dDDH analyses based on whole genome sequencing when Pseudomonas species are initially deposited in GenBank/DDBJ/EMBL databases.

2019 ◽  
Vol 69 (4) ◽  
pp. 998-1000 ◽  
Author(s):  
Wenjing Wu ◽  
Zhiyong Zong

The aim of this study was to further clarify the taxonomic relationship between the two recently described bacterial species, Lelliottia jeotgali sp. nov. and Lelliottia aquatilis sp. nov. Whole genome sequences of types strains of the two species are available for analysis. Average nucleotide identity (ANI) and in silico DNA–DNA hybridization (isDDH) values between the two type strains were determined. The ANI and isDDH values between type strains of the two species are 98.7 and 91.0 %, respectively, which are higher than cut-offs to define a bacterial species. It is therefore clear that the two species actually belong to the same species. The name of L.aquatilis was published at an earlier date than that of L. aquatilis . We therefore propose that L. aquatilis is a later heterotypic synonym of L. jeotgali .


Author(s):  
Ji Young Jung ◽  
Hye Kyeong Kang ◽  
Hyun Mi Jin ◽  
Sang-Soo Han ◽  
Young Chul Kwon ◽  
...  

A Gram-positive, facultative anaerobic, catalase-negative, non-motile, non-spore-forming and rod-shaped lactic acid bacterium strain, denoted as NFFJ11T and isolated from total mixed fermentation feed in the Republic of Korea, was characterized through polyphasic approaches, including sequence analyses of the 16S rRNA gene and housekeeping genes (rpoA and pheS), determination of average nucleotide identity and in silico DNA–DNA hybridization, fatty acid methyl ester analysis, and phenotypic characterization. Phylogenetic analyses based on 16S rRNA, rpoA and pheS gene sequences revealed that strain NFFJ11T belonged to the genus Companilactobacillus . The 16S rRNA gene sequence of strain NFFJ11T exhibited high similarity to Companilactobacillus formosensis S215T (99.66 %), Companilactobacillus farciminis Rv4 naT (99.53 %), Companilactobacillus crustorum LMG 23699T (99.19 %), Companilactobacillus futsaii YM 0097T (99.06 %), Companilactobacillus zhachilii HBUAS52074T (98.86 %) and Companilactobacillus heilongiiangensis S4-3T (98.66 %). However, average nucleotide identity and in silico DNA–DNA hybridization values for these type strains were in the range of 79.90–92.93 % and 23.80–49.30 %, respectively, which offer evidence that strain NFFJ11T belongs to a novel species of the genus Companilactobacillus . The cell-wall peptidoglycan type was A4α (l-Lys–d-Asp) and the G+C content of the genomic DNA was 35.7 mol%. The main fatty acids of strain NFFJ11T were C18 : 1  ω9c (43.3 %), C16 : 0 (20.1 %) and summed feature 7 (18.3 %; comprising any combination of C19 : 1  ω7c, C19 : 1  ω6c and C19 : 0 cyclo ω10c). Through polyphasic taxonomic analysis, it was observed that strain NFFJ11T represents a novel species belonging to the genus Companilactobacillus , for which the name Companilactobacillus pabuli sp. nov. is proposed. The type strain is NFFJ11T (= KACC 21771T= JCM 34088T).


2021 ◽  
Vol 7 (7) ◽  
Author(s):  
Casper Jamin ◽  
Sien De Koster ◽  
Stefanie van Koeveringe ◽  
Dieter De Coninck ◽  
Klaas Mensaert ◽  
...  

Whole-genome sequencing (WGS) is becoming the de facto standard for bacterial typing and outbreak surveillance of resistant bacterial pathogens. However, interoperability for WGS of bacterial outbreaks is poorly understood. We hypothesized that harmonization of WGS for outbreak surveillance is achievable through the use of identical protocols for both data generation and data analysis. A set of 30 bacterial isolates, comprising of various species belonging to the Enterobacteriaceae family and Enterococcus genera, were selected and sequenced using the same protocol on the Illumina MiSeq platform in each individual centre. All generated sequencing data were analysed by one centre using BioNumerics (6.7.3) for (i) genotyping origin of replications and antimicrobial resistance genes, (ii) core-genome multi-locus sequence typing (cgMLST) for Escherichia coli and Klebsiella pneumoniae and whole-genome multi-locus sequencing typing (wgMLST) for all species. Additionally, a split k-mer analysis was performed to determine the number of SNPs between samples. A precision of 99.0% and an accuracy of 99.2% was achieved for genotyping. Based on cgMLST, a discrepant allele was called only in 2/27 and 3/15 comparisons between two genomes, for E. coli and K. pneumoniae, respectively. Based on wgMLST, the number of discrepant alleles ranged from 0 to 7 (average 1.6). For SNPs, this ranged from 0 to 11 SNPs (average 3.4). Furthermore, we demonstrate that using different de novo assemblers to analyse the same dataset introduces up to 150 SNPs, which surpasses most thresholds for bacterial outbreaks. This shows the importance of harmonization of data-processing surveillance of bacterial outbreaks. In summary, multi-centre WGS for bacterial surveillance is achievable, but only if protocols are harmonized.


Author(s):  
Nay C. Dia ◽  
Johan Van Vaerenbergh ◽  
Cinzia Van Malderghem ◽  
Jochen Blom ◽  
Theo H. M. Smits ◽  
...  

This paper describes a novel species isolated in 2011 and 2012 from nursery-grown Hydrangea arborescens cultivars in Flanders, Belgium. After 4 days at 28 °C, the strains yielded yellow, round, convex and mucoid colonies. Pathogenicity of the strains was confirmed on its isolation host, as well as on Hydrangea quercifolia. Analysis using MALDI-TOF MS identified the Hydrangea strains as belonging to the genus Xanthomonas but excluded them from the species Xanthomonas hortorum . A phylogenetic tree based on gyrB confirmed the close relation to X. hortorum . Three fatty acids were dominant in the Hydrangea isolates: anteiso-C15 : 0, iso-C15 : 0 and summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c). Unlike X. hortorum pathovars, the Hydrangea strains were unable to grow in the presence of lithium chloride and could only weakly utilize d-fructose-6-PO4 and glucuronamide. Phylogenetic characterization based on multilocus sequence analysis and phylogenomic characterization revealed that the strains are close to, yet distinct from, X. hortorum . The genome sequences of the strains had average nucleotide identity values ranging from 94.35–95.19 % and in silico DNA–DNA hybridization values ranging from 55.70 to 59.40 % to genomes of the X. hortorum pathovars. A genomics-based loop-mediated isothermal amplification assay was developed which was specific to the Hydrangea strains for its early detection. A novel species, Xanthomonas hydrangeae sp. nov., is proposed with strain LMG 31884T (=CCOS 1956T) as the type strain.


2021 ◽  
Vol 7 (11) ◽  
Author(s):  
Isabelle Bernaquez ◽  
Christiane Gaudreau ◽  
Pierre A. Pilon ◽  
Sadjia Bekal

Many public health laboratories across the world have implemented whole-genome sequencing (WGS) for the surveillance and outbreak detection of foodborne pathogens. PulseNet-affiliated laboratories have determined that most single-strain foodborne outbreaks are contained within 0–10 multi-locus sequence typing (MLST)-based allele differences and/or core genome single-nucleotide variants (SNVs). In addition to being a food- and travel-associated outbreak pathogen, most Shigella spp. cases occur through continuous person-to-person transmission, predominantly involving men who have sex with men (MSM), leading to long-term and recurrent outbreaks. Continuous transmission patterns coupled to genetic evolution under antibiotic treatment pressure require an assessment of existing WGS-based subtyping methods and interpretation criteria for cluster inclusion/exclusion. An evaluation of 4 WGS-based subtyping methods [SNVPhyl, coreMLST, core genome MLST (cgMLST) and whole-genome MLST (wgMLST)] was performed on 9 foodborne-, travel- and MSM-related retrospective outbreaks from a collection of 91 Shigella flexneri and 232  Shigella sonnei isolates to determine the methods’ epidemiological concordance, discriminatory power, robustness and ability to generate stable interpretation criteria. The discriminatory powers were ranked as follows: coreMLST<SNVPhyl<cgMLST<wgMLST (range: 0.970–1.000). The genetic differences observed for non-MSM-related Shigella spp. outbreaks respect the standard 0–10 allele/SNV guideline; however, mobile genetic element (MGE)-encoded loci caused inflated genetic variation and discrepant phylogenies for prolonged MSM-related S. sonnei outbreaks via wgMLST. The S. sonnei correlation coefficients of wgMLST were also the lowest at 0.680, 0.703 and 0.712 for SNVPhyl, coreMLST and cgMLST, respectively. Plasmid maintenance, mobilization and conjugation-associated genes were found to be the main source of genetic distance inflation in addition to prophage-related genes. Duplicated alleles arising from the repeated nature of IS elements were also responsible for many false cg/wgMLST differences. The coreMLST approach was shown to be the most robust, followed by SNVPhyl and wgMLST for inter-laboratory comparability. Our results highlight the need for validating species-specific subtyping methods based on microbial genome plasticity and outbreak dynamics in addition to the importance of filtering confounding MGEs for cluster detection.


2020 ◽  
Vol 70 (5) ◽  
pp. 3547-3552 ◽  
Author(s):  
Mari Tohya ◽  
Shin Watanabe ◽  
Tatsuya Tada ◽  
Htay Htay Tin ◽  
Teruo Kirikae

This study was conducted to clarify the taxonomic status of the species Pseudomonas fuscovaginae and Pseudomonas shirazica . Whole genome sequences for the type strains of P. fuscovaginae and P. shirazica were compared against the closely related type strains of the Pseudomonas putida group and the Pseudomonas fluorescens group species. Average nucleotide identity and digital DNA–DNA hybridization values between P. fuscovaginae LMG 2158T and Pseudomonas asplenii ATCC 23835T were 98.4 and 85.5 %, and between P. shirazica VM14T and Pseudomonas asiatica RYU5T were 99.3 and 95.3 %. These values were greater than recognized thresholds for bacterial species delineation, indicating that they belong to the same genomospecies, respectively. Therefore, P. fuscovaginae and P. shirazica should be reclassified as later heterotypic synonyms of P. asplenii and P. asiatica , respectively.


2020 ◽  
Vol 6 (7) ◽  
Author(s):  
Bede Constantinides ◽  
Kevin K. Chau ◽  
T. Phuong Quan ◽  
Gillian Rodger ◽  
Monique I. Andersson ◽  
...  

Escherichia coli and Klebsiella spp. are important human pathogens that cause a wide spectrum of clinical disease. In healthcare settings, sinks and other wastewater sites have been shown to be reservoirs of antimicrobial-resistant E. coli and Klebsiella spp., particularly in the context of outbreaks of resistant strains amongst patients. Without focusing exclusively on resistance markers or a clinical outbreak, we demonstrate that many hospital sink drains are abundantly and persistently colonized with diverse populations of E. coli , Klebsiella pneumoniae and Klebsiella oxytoca , including both antimicrobial-resistant and susceptible strains. Using whole-genome sequencing of 439 isolates, we show that environmental bacterial populations are largely structured by ward and sink, with only a handful of lineages, such as E. coli ST635, being widely distributed, suggesting different prevailing ecologies, which may vary as a result of different inputs and selection pressures. Whole-genome sequencing of 46 contemporaneous patient isolates identified one (2 %; 95 % CI 0.05–11 %) E. coli urine infection-associated isolate with high similarity to a prior sink isolate, suggesting that sinks may contribute to up to 10 % of infections caused by these organisms in patients on the ward over the same timeframe. Using metagenomics from 20 sink-timepoints, we show that sinks also harbour many clinically relevant antimicrobial resistance genes including bla CTX-M, bla SHV and mcr, and may act as niches for the exchange and amplification of these genes. Our study reinforces the potential role of sinks in contributing to Enterobacterales infection and antimicrobial resistance in hospital patients, something that could be amenable to intervention. This article contains data hosted by Microreact.


Author(s):  
Antonio Castellano-Hinojosa ◽  
David Correa-Galeote ◽  
Martha-Helena Ramírez-Bahena ◽  
Germán Tortosa ◽  
Jesús González-López ◽  
...  

Two endophytic strains, coded MOVP5T and MOPV6, were isolated from nodules of Phaseolus vulgaris plants grown on agricultural soil in Southeastern Spain, and were characterized through a polyphasic taxonomy approach. Their 16S rRNA gene sequences showed 99.3 and 99.4 %, 98.9 and 99.6 %, and 99.0 and 98.7% similarity to ‘ A. deltaense ’ YIC 4121T, A. radiobacter LGM 140T, and A. pusense NRCPB10T, respectively. Multilocus sequence analysis based on sequences of recA and atpD genes suggested that these two strains could represent a new Agrobacterium species with less than 96.5 % similarity to their closest relatives. PCR amplification of the telA gene, involved in synthesis of protelomerase, confirmed the affiliation of strains MOPV5T and MOPV6 to the genus Agrobacterium . Whole genome average nucleotide identity and digital DNA–DNA hybridization average values were less than 95.1 and 66.7 %, respectively, with respect to its closest related species. Major fatty acids in strain MOPV5T were C18 : 1 ω7c/C18 : 1 ω6c in summed feature 8, C19 : 0 cyclo ω8c, C16 : 0 and C16 : 0 3-OH. Colonies were small to medium, pearl-white coloured on YMA at 28 °C and growth was observed at 10–42 °C, pH 5.0–10.0 and with 0.0–0.5 % (w/v) NaCl. The DNA G+C content was 59.9 mol%. These two strains differ from all other genomovars of Agrobacterium found so far, including those that have not yet given a Latin name. The combined genotypic, phenotypic and chemotaxonomic data support the classification of strain MOPV5T as representing a novel species of Agrobacterium , for which the name Agrobacterium leguminum sp. nov. is proposed. The type strain is MOPV5T (=CECT 30096T=LMG 31779T).


Author(s):  
Kaiqin Li ◽  
Siren Hu ◽  
Yinfeng Wang ◽  
Yihui Guo ◽  
Meiliang Zhou ◽  
...  

As two separate genomic species, Streptomyces calvus and Streptomyces aureorectus were approved in 1980 and 1986, respectively. However, recently, it has been found that the average nucleotide identity and digital DNA–DNA hybridization values between S. calvus JCM 4326T and S. aureorectus DSM 41692T were 99.19 and 92.70 %, respectively, much higher than 95–96 and 70  % cut-off points proposed and the generally accepted species boundaries. These data indicated that they should be classified as the same genomic species. Furthermore, this result was also supported by a comprehensive comparison of phenotypic, chemotaxonomic and physio-biochemical characteristics between the two type strains. All these data indicated that S. calvus and S. aureorectus had the same taxonomic position. In accordance with the principle of priority, it is proposed that S. aureorectus is a later heterotypic synonyms of S. calvus .


2021 ◽  
Vol 7 (12) ◽  
Author(s):  
Bojan Papić ◽  
Majda Golob ◽  
Irena Zdovc ◽  
Jana Avberšek ◽  
Metka Pislak Ocepek ◽  
...  

The spore-forming bacterium Paenibacillus larvae is the causative agent of American foulbrood (AFB), a devastating disease of honeybees (Apis mellifera). In the present study, we used whole-genome sequencing (WGS) to investigate an extensive outbreak of AFB in northwestern Slovenia in 2019. A total of 59 P . larvae isolates underwent WGS, of which 40 originated from a single beekeeping operation, to assess the diversity of P. larvae within the beekeeping operation, apiary and colony. By applying a case-specific single-linkage threshold of 34 allele differences (AD), whole-genome multilocus sequence typing (wgMLST) identified two outbreak clusters represented by ERIC II-ST11 clones. All isolates from a single beekeeping operation fell within cluster 1 and the median pairwise AD between them was 10 (range=1–22). The median pairwise AD for apiaries of the same beekeeping operation ranged from 8 to 11 (min.=1, max.=22). For colonies of the same apiary and honey samples from these colonies, the median pairwise AD ranged from 8 to 14 (min.=1, max.=20). The maximum within-cluster distance was 33 pairwise AD for cluster 1 and 44 for cluster 2 isolates. The minimum distance between the outbreak-related and non-related isolates was 37 AD, confirming the importance of associated epidemiological data for delineating outbreak clusters. The observed transmission events could be explained by the activities of honeybees and beekeepers. The present study provides insight into the genetic diversity of P. larvae at different levels and thus provides information for future AFB surveillance.


Sign in / Sign up

Export Citation Format

Share Document