scholarly journals Analysis of bifidobacterial evolution using a multilocus approach

2006 ◽  
Vol 56 (12) ◽  
pp. 2783-2792 ◽  
Author(s):  
Marco Ventura ◽  
Carlos Canchaya ◽  
Antonio Del Casale ◽  
Franco Dellaglio ◽  
Erasmo Neviani ◽  
...  
Keyword(s):  
Bacterial Genome ◽  
Evolutionary Process ◽  
Housekeeping Gene ◽  
Pharmaceutical Products ◽  
Gene Sequences ◽  
Genome Sequences ◽  
Functional Ingredients ◽  
Conserved Genes ◽  
Multilocus Approach ◽  
Type Strains

Bifidobacteria represent one of the most numerous groups of bacteria found in the gastrointestinal tract of humans and animals. In man, gastrointestinal bifidobacteria are associated with health effects and for this reason they are often used as functional ingredients in food and pharmaceutical products. Such applications may benefit from or require a clear and reliable bifidobacterial species identification. The increasing number of available bacterial genome sequences has provided a large amount of housekeeping gene sequences that can be used both for identification of bifidobacterial species as well as for understanding bifidobacterial evolution. In order to assess their relative positions in the evolutionary process, fragments from seven conserved genes, clpC, dnaB, dnaG, dnaJ1, purF, rpoC and xfp, were sequenced from each of the currently described type strains of the genus Bifidobacterium. The results demonstrate that the concatenation of these seven gene sequences for phylogenetic purposes allows a significant increase in the discriminatory power between taxa.

scholarly journals Vagococcus silagei sp. nov., isolated from brewer’s grain used to make silage in Taiwan

2020 ◽  
Vol 70 (3) ◽  
pp. 1953-1960 ◽  
Author(s):  
Yen-Chi Wu ◽  
Shih-Ting Lin ◽  
Jia-Rong Guu ◽  
Tomohiko Tamura ◽  
Koji Mori ◽  
...  
Keyword(s):  
16S Rrna ◽  
Type Species ◽  
Sequence Similarity ◽  
Housekeeping Gene ◽  
Rrna Gene ◽  
Gene Sequences ◽  
Closely Related Species ◽  
Content Type ◽  
Link Type ◽  
Type Strains

A Gram-stain-positive, coccus- or oval-shaped, non-motile, haemolytic, asporogenous, catalase- and oxidase-negative, and facultatively anaerobic strain, 2B-2T, was isolated from a brewer’s grain used to make silage in Taiwan. Comparative analyses of 16S rRNA, hsp60 and pheS gene sequences demonstrated that strain 2B-2T was a member of the genus Vagococcus . On the basis of 16S rRNA gene sequence similarity, the type strains of Vagococcus teuberi (98.4 % similarity), Vagococcus carniphilus (98.4 %), Vagococcus martis (98.2 %), Vagococcus penaei (98.2 %) and Vagococcus fluvialis (98.0 %) were the closest neighbours to this novel strain. The similarity levels of concatenated housekeeping gene sequences (hsp60 and pheS) between strain 2B-2T and these closely related species ranged from 84.5 to 88.0 %. The average nucleotide identity and in silico DNA–DNA hybridization values between strain 2B-2T and its closest relatives were lower than 72.9 and 21.6 %, respectively. The DNA G+C content was 34.7 mol%. Phenotypic and genotypic features demonstrated that strain 2B-2T represents a novel species of the genus Vagococcus , for which the name Vagococcus silagei sp. nov. is proposed. The type strain is 2B-2T (=BCRC 81132T=NBRC 113536T).

scholarly journals Defining the Rhizobium leguminosarum Species Complex

Genes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 111 ◽  
Author(s):  
J. Peter W. Young ◽  
Sara Moeskjær ◽  
Alexey Afonin ◽  
Praveen Rahi ◽  
Marta Maluk ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
Species Complex ◽  
Rhizobium Leguminosarum ◽  
Housekeeping Genes ◽  
Single Species ◽  
Natural Unit ◽  
Genome Sequences ◽  
Distinct Entity ◽  
Type Strains ◽  
Core Genes

Bacteria currently included in Rhizobium leguminosarum are too diverse to be considered a single species, so we can refer to this as a species complex (the Rlc). We have found 429 publicly available genome sequences that fall within the Rlc and these show that the Rlc is a distinct entity, well separated from other species in the genus. Its sister taxon is R. anhuiense. We constructed a phylogeny based on concatenated sequences of 120 universal (core) genes, and calculated pairwise average nucleotide identity (ANI) between all genomes. From these analyses, we concluded that the Rlc includes 18 distinct genospecies, plus 7 unique strains that are not placed in these genospecies. Each genospecies is separated by a distinct gap in ANI values, usually at approximately 96% ANI, implying that it is a ‘natural’ unit. Five of the genospecies include the type strains of named species: R. laguerreae, R. sophorae, R. ruizarguesonis, “R. indicum” and R. leguminosarum itself. The 16S ribosomal RNA sequence is remarkably diverse within the Rlc, but does not distinguish the genospecies. Partial sequences of housekeeping genes, which have frequently been used to characterize isolate collections, can mostly be assigned unambiguously to a genospecies, but alleles within a genospecies do not always form a clade, so single genes are not a reliable guide to the true phylogeny of the strains. We conclude that access to a large number of genome sequences is a powerful tool for characterizing the diversity of bacteria, and that taxonomic conclusions should be based on all available genome sequences, not just those of type strains.

Integrating genomics into the taxonomy and systematics of the Bacteria and Archaea

2014 ◽  
Vol 64 (Pt_2) ◽  
pp. 316-324 ◽  
Author(s):  
Jongsik Chun ◽  
Fred A. Rainey
Keyword(s):  
Genomic Sequence ◽  
Sequence Data ◽  
Original Research ◽  
Rrna Gene ◽  
New Taxon ◽  
Genome Sequences ◽  
Microbial World ◽  
Content Type ◽  
Link Type ◽  
Type Strains

The polyphasic approach used today in the taxonomy and systematics of the Bacteria and Archaea includes the use of phenotypic, chemotaxonomic and genotypic data. The use of 16S rRNA gene sequence data has revolutionized our understanding of the microbial world and led to a rapid increase in the number of descriptions of novel taxa, especially at the species level. It has allowed in many cases for the demarcation of taxa into distinct species, but its limitations in a number of groups have resulted in the continued use of DNA–DNA hybridization. As technology has improved, next-generation sequencing (NGS) has provided a rapid and cost-effective approach to obtaining whole-genome sequences of microbial strains. Although some 12 000 bacterial or archaeal genome sequences are available for comparison, only 1725 of these are of actual type strains, limiting the use of genomic data in comparative taxonomic studies when there are nearly 11 000 type strains. Efforts to obtain complete genome sequences of all type strains are critical to the future of microbial systematics. The incorporation of genomics into the taxonomy and systematics of the Bacteria and Archaea coupled with computational advances will boost the credibility of taxonomy in the genomic era. This special issue of International Journal of Systematic and Evolutionary Microbiology contains both original research and review articles covering the use of genomic sequence data in microbial taxonomy and systematics. It includes contributions on specific taxa as well as outlines of approaches for incorporating genomics into new strain isolation to new taxon description workflows.

Reclassification of Parvularcula flava as Aquisalinus luteolus nom. nov. and emended description of the genus Aquisalinus

2021 ◽  
Vol 71 (10) ◽  
Author(s):  
Jun-Jie Ying ◽  
Zhi-Cheng Wu ◽  
Yuan-Chun Fang ◽  
Lin Xu ◽  
Cong Sun
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Species ◽  
Comparative Genomic ◽  
Rrna Gene ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Content Type ◽  
Link Type ◽  
Type Strains

Parvularcula flava was proposed as a novel member of genus Parvularcula in 2016. Some time earlier, Aquisalinus flavus has been proposed as a novel species of a novel genus named Aquisalinus . When comparing the 16S rRNA gene sequences of type strains P. flava NH6-79T and A. flavus D11M-2T, they showed 97.9 % sequence identity, much higher than the sequence identities 92.7–94.3 % between P. flava NH6-79T and type strains in the genus Parvularcula , indicating that the later proposed novel taxon Parvularcula flava need reclassification. The phylogenetic trees based on 16S rRNA gene sequences and genome sequences both showed that P. flava NH6-79T and A. flavus D11M-2T formed a separated branch away from strains in the genera Parvularcula , Marinicaulis and Amphiplicatus . The average amino acid identity and average nucleotide identity values of P. flava NH6-79T and A. flavus D11M-2T were 87.9 and 85.0 %, respectively, much higher than the values between P. flava NH6-79T and other closely related type strains (54.3 %–58.1 % and 68.6–70.4 %, respectively). P. flava NH6-79T and A. flavus D11M-2T also contained summed feature 8 (C18 : 1  ω6c and/or C18 : 1  ω7c) and C16 : 0 as major fatty acids, distinguishing them from other closely related taxa. Based on the results of the phylogenetic, comparative genomic and phenotypic analyses, Parvularcula flava should be reclassified as Aquisalinus luteolus nom. nov. and the description of genus Aquisalinus is emended.

scholarly journals Draft Genome Sequences of Type Strains Bacillus drentensis DSM 15600 T and Bacillus novalis DSM 15603 T

2016 ◽  
Vol 4 (6) ◽  
Author(s):  
Bo Liu ◽  
Guo-Hong Liu ◽  
Yu-jing Zhu ◽  
Jie-Ping Wang ◽  
Jian-Mei Che ◽  
...  
Keyword(s):  
Draft Genome ◽  
Functional Gene ◽  
Genome Sequences ◽  
Gene Mining ◽  
Type Strains

Here, we report the draft genome sequences of Bacillus drentensis DSM 15600 T and Bacillus novalis DSM 15603 T with 5,305,306 bp and 5,667,584 bp, respectively, which will provide useful information for the functional gene mining and application of these two species. The average DNA G+C contents were 38.91% and 40.01%, respectively.

scholarly journals Closed and High-Quality Bacterial Genome Sequences of the Oligo-Mouse-Microbiota Community

2021 ◽  
Vol 10 (17) ◽  
Author(s):  
Quentin Lamy-Besnier ◽  
Romain Koszul ◽  
Laurent Debarbieux ◽  
Martial Marbouty
Keyword(s):  
Murine Model ◽  
Bacterial Genome ◽  
Chromosome Conformation Capture ◽  
Genome Sequences ◽  
Pacbio Sequencing ◽  
High Quality ◽  
Chromosome Conformation

ABSTRACT The Oligo-Mouse-Microbiota (OMM12) gnotobiotic murine model is an increasingly popular model in microbiota studies. However, following Illumina and PacBio sequencing, the genomes of the 12 strains could not be closed. Here, we used genomic chromosome conformation capture (Hi-C) data to reorganize, close, and improve the quality of these 12 genomes.

scholarly journals Bactopia: a flexible pipeline for complete analysis of bacterial genomes

2020 ◽  
Author(s):  
Robert A. Petit ◽  
Timothy D. Read
Keyword(s):  
Standard Procedure ◽  
Bacterial Species ◽  
Bacterial Genome ◽  
Complete Analysis ◽  
Comparative Genomic ◽  
Bacterial Genomes ◽  
Analysis Pipeline ◽  
Genomic Analyses ◽  
Conserved Genes ◽  
Downstream Analysis

AbstractSequencing of bacterial genomes using Illumina technology has become such a standard procedure that often data are generated faster than can be conveniently analyzed. We created a new series of pipelines called Bactopia, built using Nextflow workflow software, to provide efficient comparative genomic analyses for bacterial species or genera. Bactopia consists of a dataset setup step (Bactopia Datasets; BaDs) where a series of customizable datasets are created for the species of interest; the Bactopia Analysis Pipeline (BaAP), which performs quality control, genome assembly and several other functions based on the available datasets and outputs the processed data to a structured directory format; and a series of Bactopia Tools (BaTs) that perform specific post-processing on some or all of the processed data. BaTs include pan-genome analysis, computing average nucleotide identity between samples, extracting and profiling the 16S genes and taxonomic classification using highly conserved genes. It is expected that the number of BaTs will increase to fill specific applications in the future. As a demonstration, we performed an analysis of 1,664 public Lactobacillus genomes, focusing on L. crispatus, a species that is a common part of the human vaginal microbiome. Bactopia is an open source system that can scale from projects as small as one bacterial genome to thousands that allows for great flexibility in choosing comparison datasets and options for downstream analysis. Bactopia code can be accessed at https://www.github.com/bactopia/bactopia.

Taxonomic study of the genus Salinicola: transfer of Halomonas salaria and Chromohalobacter salarius to the genus Salinicola as Salinicola salarius comb. nov. and Salinicola halophilus nom. nov., respectively

2010 ◽  
Vol 60 (4) ◽  
pp. 963-971 ◽  
Author(s):  
Rafael R. de la Haba ◽  
Cristina Sánchez-Porro ◽  
M. Carmen Márquez ◽  
Antonio Ventosa
Keyword(s):  
16S Rrna ◽  
Type Strain ◽  
Phylogenetic Trees ◽  
23S Rrna ◽  
Rrna Gene ◽  
Gene Sequences ◽  
The Family ◽  
23S Rrna Gene ◽  
Single Genus ◽  
Type Strains

We have carried out a polyphasic taxonomic characterization of the type strains of the species with the recently validated name Salinicola socius, together with two species that were phylogenetically closely related, Halomonas salaria and Chromohalobacter salarius. 16S rRNA gene sequence analyses showed that they constituted a coherent cluster, with sequence similarities between 98.7 and 97.7 %. We have determined the almost complete 23S rRNA gene sequences of these three type strains, and the percentage of similarity between them was 99.2–97.6 %. Phylogenetic trees based on the 16S rRNA and 23S rRNA gene sequences, obtained by using three different algorithms, were consistent and showed that these three species constituted a cluster separated from the other species of the genera of the family Halomonadaceae, supporting their placement in a single genus. All three species have ubiquinone 9 as the major respiratory quinone, and showed similar fatty acid and polar lipid profiles. The level of DNA–DNA hybridization between Salinicola socius DSM 19940T, Halomonas salaria DSM 18044T and Chromohalobacter salarius CECT 5903T was 41–21 %, indicating that they are different species of the genus Salinicola. A comparative phenotypic study of these strains following the proposed minimal standards for describing new taxa of the family Halomonadaceae has been carried out. The phenotypic data are consistent with the placement of these three species in a single genus and support their differentiation at the species level. On the basis of these data we have emended the description of the species Salinicola socius and we propose to transfer the species Halomonas salaria and Chromohalobacter salarius to the genus Salinicola, as Salinicola salarius comb. nov. (type strain M27T =KCTC 12664T =DSM 18044T) and Salinicola halophilus nom. nov. (type strain CG4.1T =CECT 5903T =LMG 23626T), respectively.

scholarly journals Draft Genome Sequences of 64 Type Strains of 50 Species and 25 Subspecies of the Genus Staphylococcus Rosenbach 1884

2019 ◽  
Vol 8 (17) ◽  
Author(s):  
Kevin Cole ◽  
Dona Foster ◽  
Julie E. Russell ◽  
Tanya Golubchik ◽  
Martin Llewelyn ◽  
...  
Keyword(s):  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Draft Genome ◽  
Whole Genome ◽  
Genome Sequences ◽  
Accurate Identification ◽  
Access To Data ◽  
Type Strains

Members of the genus Staphylococcus have been isolated from humans, animals, and the environment. Accurate identification with whole-genome sequencing requires access to data derived from type strains.

scholarly journals Complete Genome Sequences of Two Acetylene-Fermenting Pelobacter acetylenicus Strains

2017 ◽  
Vol 5 (6) ◽  
Author(s):  
John M. Sutton ◽  
Shaun M. Baesman ◽  
Janna L. Fierst ◽  
Amisha T. Poret-Peterson ◽  
Ronald S. Oremland ◽  
...  
Keyword(s):  
Complete Genome ◽  
Genome Sequences ◽  
Content Type ◽  
Pelobacter Acetylenicus ◽  
Type Strains

ABSTRACT Acetylene fermentation is a rare metabolism that was serendipitously discovered during C2H2-block assays of N2O reductase. Here, we report the genome sequences of two type strains of acetylene-fermenting Pelobacter acetylenicus, the freshwater bacterium DSM 3246 and the estuarine bacterium DSM 3247.

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