scholarly journals Whole Genome Sequence-Based Identification of Clostridium estertheticum Complex Strains Supports the Need for Taxonomic Reclassification Within the Species Clostridium estertheticum

2021 ◽  
Vol 12 ◽  
Author(s):  
Joseph Wambui ◽  
Nicole Cernela ◽  
Marc J. A. Stevens ◽  
Roger Stephan

Isolates within the Clostridium estertheticum complex (CEC) have routinely been identified through the 16S rRNA sequence, but the high interspecies sequence similarity reduces the resolution necessary for species level identification and often results in ambiguous taxonomic classification. The current study identified CEC isolates from meat juice (MJS) and bovine fecal samples (BFS) and determined the phylogeny of species within the CEC through whole genome sequence (WGS)-based analyses. About 1,054 MJS were screened for CEC using quantitative real-time PCR (qPCR). Strains were isolated from 33 MJS and 34 BFS qPCR-positive samples, respectively. Pan- and core-genome phylogenomics were used to determine the species identity of the isolates. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) were used to validate the species identity. The phylogeny of species within the CEC was determined through a combination of these methods. Twenty-eight clostridia strains were isolated from MJS and BFS samples out of which 13 belonged to CEC. At 95% ANI and 70% dDDH thresholds for speciation, six CEC isolates were identified as genomospecies2 (n=3), Clostridium tagluense (n=2) and genomospecies3 (n=1). Lower thresholds of 94% ANI and 58% dDDH were required for the classification of seven CEC isolates into species C. estertheticum and prevent an overlap between species C. estertheticum and Clostridium frigoriphilum. Combination of the two species and abolishment of current subspecies classification within the species C. estertheticum are proposed. These data demonstrate the suitability of phylogenomics to identify CEC isolates and determine the phylogeny within CEC.

2021 ◽  
Author(s):  
Dawoon Chung ◽  
Jaoon Young Hwan Kim ◽  
Kyung Woo Kim ◽  
Yong Min Kwon

Abstract A gram-negative, orange-pigmented, non-flagellated, gliding, rod-shaped, and aerobic bacterium, designated strain F202Z8T, was isolated from a rusty iron plate found in the intertidal region of Taean, South Korea. Notably, this strain synthesized silver nanoparticles (AgNPs), and 17 putative genes responsible for the synthesis of AgNPs were found in its genome. The complete genome sequence of strain F202Z8T is 4,723,614 bp, with 43.26% G + C content. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain F202Z8T forms a distinct lineage with closely related genera Maribacter, Pelagihabitans, Pseudozobellia, Zobellia, Pricia, and Costertonia belonging to the family Flavobacteriaceae. The 16S rRNA sequence similarity was < 94.5%. The digital DNA–DNA hybridization and average nucleotide identity values calculated from the whole genome-sequence comparison between strain F202Z8T and other members of the family Flavobacteriaceae were in the ranges of 12.7–16.9% and 70.3–74.4%, respectively. Growth was observed at 15–33°C (optimally at 30°C), at pH 6.5–7.5 (optimally at pH 7.0), and with the addition of 2.5–4.5% (w/v) NaCl to the media (optimally at 4.0%). The predominant cellular fatty acids were iso-C15: 0, iso-C15 :1 G, and iso-C17 :0 3-OH; the major respiratory quinone was MK-6. Polar lipids included phosphatidylethanolamine, five unidentified lipids, and two unidentified aminolipids. Our polyphasic taxonomic results suggested that this strain represents a novel species of a novel genus in the family Flavobacteriaceae, for which the name Aggregatimonas sangjinii gen. nov., sp. nov. is proposed. The type strain of Aggregatimonas sangjinii is F202Z8T (= KCCM 43411T = LMG 31494T).


2015 ◽  
Vol 3 (6) ◽  
Author(s):  
Phuong N. Tran ◽  
Nicholas E. H. Tan ◽  
Yin Peng Lee ◽  
Han Ming Gan ◽  
Steven J. Polter ◽  
...  

Here, we report the whole-genome sequences and annotation of 11 endophytic bacteria from poison ivy ( Toxicodendron radicans ) vine tissue. Five bacteria belong to the genus Pseudomonas , and six single members from other genera were found present in interior vine tissue of poison ivy.


2013 ◽  
Vol 63 (Pt_7) ◽  
pp. 2742-2751 ◽  
Author(s):  
Henryk Urbanczyk ◽  
Yoshitoshi Ogura ◽  
Tetsuya Hayashi

Use of inadequate methods for classification of bacteria in the so-called Harveyi clade (family Vibrionaceae, Gammaproteobacteria) has led to incorrect assignment of strains and proliferation of synonymous species. In order to resolve taxonomic ambiguities within the Harveyi clade and to test usefulness of whole genome sequence data for classification of Vibrionaceae, draft genome sequences of 12 strains were determined and analysed. The sequencing included type strains of seven species: Vibrio sagamiensis NBRC 104589T, Vibrio azureus NBRC 104587T, Vibrio harveyi NBRC 15634T, Vibrio rotiferianus LMG 21460T, Vibrio campbellii NBRC 15631T, Vibrio jasicida LMG 25398T, and Vibrio owensii LMG 25443T. Draft genome sequences of strain LMG 25430, previously designated the type strain of [Vibrio communis], and two strains (MWB 21 and 090810c) from the ‘beijerinckii’ lineage were also determined. Whole genomes of two additional strains (ATCC 25919 and 200612B) that previously could not be assigned to any Harveyi clade species were also sequenced. Analysis of the genome sequence data revealed a clear case of synonymy between V. owensii and [V. communis], confirming an earlier proposal to synonymize both species. Both strains from the ‘beijerinckii’ lineage were classified as V. jasicida, while the strains ATCC 25919 and 200612B were classified as V. owensii and V. campbellii, respectively. We also found that two strains, AND4 and Ex25, are closely related to Harveyi clade bacteria, but could not be assigned to any species of the family Vibrionaceae. The use of whole genome sequence data for the taxonomic classification of the Harveyi clade bacteria and other members of the family Vibrionaceae is also discussed.


2020 ◽  
Author(s):  
Antonio Roberto Gomes de Farias ◽  
Wilson José da Silva Junior ◽  
José Bandeira do Nascimento Junior ◽  
Valdir de Queiroz Balbino ◽  
Ana Maria Benko-Iseppon ◽  
...  

Abstract Background Xanthomonas citri pv. viticola is one of the most critical grapevine diseases in the Northeast of Brazil, presenting a high risk to Brazilian and worldwide areas of grape production. The X.citri pv. viticola epithet was recently proposed to be changed from X. campestris pv. v iticola based on multilocus sequence analysis and whole-genome sequences. Besides, genomics has revolutionized the field of bacteriology, by associating genome sequencing with comparative analysis such as in silico analysis such as DNA-DNA hybridization, average nucleotide identity, distance between genomes, pan-genomic approach, and phylogenomic, providing valuable insights and knowledge about virulence factors and contributing to increase the understanding and clarifying the taxonomic relationship of Xanthomonas and others prokaryotic species.Results We used the whole-genome sequence of three Brazilian strains and the pathotype to characterize X.citri pv. viticola accessions plus 124 whole-genome sequences of Xanthomonas species available in NCBI, comprising 13 species and 15 pathovars. The whole-genome sequence structure of X. citri pv. viticola was shown presents a high level of conservation concerning other X. citri species. Pan-genomic approaches, average nucleotide identity analysis, and in silico DNA-DNA hybridization were carried out, allowing X.citri pv. viticola characterization and inferences on the phylogenetic relationships within Xanthomonas . The analysis of the sequence of the 128 genomes clustered the Xanthomonas strains in eight main groups according to the recently proposed classification in all approaches used. Also, the analysis revealed that X. hortorum and X. gardneri should be classified as a single species, and the strain 17 of X. campestris and XC01 of X. citri pv. mangiferaeindicae widely described in the literature are misclassified.Conclusions We performed the genomic characterization of three representative Brazilian strains of Xcv . The genomic approaches based in the pan-genome, average nucleotide identity, and in silico DNA-DNA hybridization support the proposed taxonomic position of X.citri pv. viticola and of the recently proposed Xanthomonas species and pathovars. In addition, we detected species delimitation of the misclassified Xanthomonas strains with extensive studies reported in the literature.


2017 ◽  
Author(s):  
Daniel Shriner ◽  
Charles N. Rotimi

ABSTRACTFive classical designations of sickle haplotypes are based on the presence/absence of restriction sites and named after ethnic groups or geographic regions from which patients originated. Each haplotype is thought to represent an independent occurrence of the sickle mutation. We investigated the origins of the sickle mutation using whole genome sequence data. We identified 156 carriers from the 1000 Genomes Project, the African Genome Variation Project, and Qatar. We defined a new haplotypic classification using 27 polymorphisms in linkage disequilibrium with rs334. Network analysis revealed a common haplotype that differed from the ancestral haplotype only by the derived sickle mutation at rs334 and correlated collectively with the Central African Republic/Bantu, Cameroon, and Arabian/Indian designations. Other haplotypes were derived from this haplotype and fell into two clusters, one comprised of haplotypes correlated with the Senegal designation and the other comprised of haplotypes correlated with both the Benin and Senegal designations. The near-exclusive presence of the original sickle haplotype in the Central African Republic, Kenya, Uganda, and South Africa is consistent with this haplotype predating the Bantu Expansion. Modeling of balancing selection indicated that the heterozygote advantage was 15.2%, an equilibrium frequency of 12.0% was reached after 87 generations, and the selective environment predated the mutation. The posterior distribution of the ancestral recombination graph yielded an age of the sickle mutation of 259 generations, corresponding to 7,300 years and the Holocene Wet Phase. These results clarify the origin of the sickle allele and improve and simplify the classification of sickle haplotypes.


2010 ◽  
Vol 36 (4) ◽  
pp. 688-694
Author(s):  
Yi-Jun WANG ◽  
Yan-Ping LÜ ◽  
Qin XIE ◽  
De-Xiang DENG ◽  
Yun-Long BIAN

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