JSpeciesWS: a web server for prokaryotic species circumscription based on pairwise genome comparison
Bioinformatics, 32(6), 2016, 929–931
doi: 10.1093/bioinformatics/btv681
Advance Access Publication Date: 16 November 2015
Applications Note
Genome analysis
JSpeciesWS: a web server for prokaryotic
species circumscription based on pairwise
genome comparison
-Mo
ra2, Frank Oliver Glöckner3,4
Michael Richter1,*, Ramon Rossello
and Jörg Peplies1
1
Ribocon GmbH, Fahrenheitstraße. 1, 28359 Bremen, Germany, 2Marine Microbiology Group, Mediterranean
Institute for Advanced Studies, C/ Miquel Marqués, 21, 07190, Esporles, Spain, 3Max Planck Institute for Marine
Microbiology, Microbial Genomics and Bioinformatics Research Group, Celsiusstraße 1, 28359 Bremen, Germany
and 4Jacobs University gGmbH Bremen, Department of Life Sciences and Chemistry, Campus Ring 1, 28759
Bremen, Germany
*To whom correspondence should be addressed.
Associate Editor: John Hancock
Received on September 10, 2015; revised on October 29, 2015; accepted on November 12, 2015
Abstract
Summary: JSpecies Web Server (JSpeciesWS) is a user-friendly online service for in silico calculating the extent of identity between two genomes, a parameter routinely used in the process of polyphasic microbial species circumscription. The service measures the average nucleotide identity
(ANI) based on BLASTþ (ANIb) and MUMmer (ANIm), as well as correlation indexes of tetranucleotide signatures (Tetra). In addition, it provides a Tetra Correlation Search function, which
allows to rapidly compare selected genomes against a continuously updated reference database
with currently about 32 000 published whole and draft genome sequences. For comparison, own
genomes can be uploaded and references can be selected from the JSpeciesWS reference database. The service indicates whether two genomes share genomic identities above or below the
species embracing thresholds, and serves as a fast way to allocate unknown genomes in the frame
of the hitherto sequenced species.
Availability and implementation: JSpeciesWS is available at http://jspecies.ribohost.com/
jspeciesws.
Supplementary information: Supplementary data are available at Bioinformatics online.
Contact:
1 Introduction
DNA-DNA-hybridization (DDH) measures the degree of genomic
similarity between two pools of DNA molecules. Despite that distinct DDH determination methods frequently lead to different results, since nearly 50 years it is considered as the gold standard for
species delineation (Rossell
o-M
ora and Amann, 2015). In times of
cost-efficient sequencing with scientists having easy access to thousands of publicly available genome sequences, the species delineation based on user friendly computational pairwise genome
comparisons to determine overall genome relatedness indices
C The Author 2015. Published by Oxford University Press.
V
[OGRI, (Chun and Rainey, 2014)] has emerged. This approach has
already been widely accepted by the scientific community (Colston
et al., 2014; Li et al., 2015; Lugli et al., 2014; Oren and Garrity,
2014) and specialized tools like the stand-alone software JSpecies
(Richter and Rossell
o-M
ora, 2009) or similar solutions (MeierKolthoff et al., 2013) have proven to provide valuable OGRI results.
Here we present the JSpecies Web Server (JSpeciesWS) a webbased implementation of the core features of the original JSpecies
software for easy user-access and extended functionality. It represents the latest development of JSpecies in terms of usability,
929
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/),
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930
flexibility, and efficiency. An online reference database of all published whole and draft genomes (about 32 000) with pre-calculated
OGRI results has been added and can be searched in seconds based
on genome comparison using the new Tetra Correlation Search
(TCS) function.
2 Methods
2.1 Average nucleotide identity based on BLAST1
The average nucleotide identity based on BLAST þ (ANIb) calculation is implemented as described by Goris et al. (2007). In contrast
to the original JSpecies stand-alone implementation, the web server
uses BLAST version 2.2.29 þ (Camacho et al., 2009) instead of
BLAST version 2.2.26 (Altschul et al., 1997).
2.2 Average nucleotide identity based on MUMmer
For average nucleotide identity based on MUMmer (ANIm) calculation, the dnadiff script of the MUMmer tool version 3.0 (Kurtz
et al., 2004) is used instead of a self-written parser used by the original JSpecies stand-alone implementation.
2.3 Tetra-nucleotide signature correlation index
Tetra is an alignment-free parameter correlating with ANI, and implemented in the same way as the original JSpecies stand-alone
(Richter and Rossell
o-M
ora, 2009).
2.4 Tetra Correlation Search
TCS is a new feature of JSpeciesWS that allows rapid comparisons
against the JSpeciesWS reference database, providing a list of the
most similar genomes based on their resulting Tetra-nucleotide signature correlation index.
revisit based on session code provided) and all data will be deleted.
The limit of genomes per cart is currently set to 15.
Pairwise ANIb, ANIm or Tetra calculations can be performed
between all genomes in the cart (all vs all) or, alternatively, only one
genome of the cart can be selected for comparison against all other
genomes in the cart to reduce calculation time. In addition, a TCS
can be performed for each genome in the cart against the complete
JSpeciesWS reference database of all published whole and draft
genomes.
After starting an analysis, the status field is regularly updated
and the user is finally informed about a finished calculation by a
pop-up message. In addition, the user can provide an e-mail address
to become informed about the completion of the calculations. A all
versus all comparison of 15 genomes (210 calculations) takes on the
current system about 2 h based on ANIb, 30 min based on ANIm
and 10 min based on Tetra. All results can be revisited, exported for
further processing and shared among users.
4 Conclusion
Recent studies have shown that electronic (in silico) pairwise OGRI
can replace standard laboratory-based DDH in order to simplify,
and at the same time substantiate, this central aspect of prokaryotic
species delineation. In addition, OGRI allows taxonomists to
quickly verify the species affiliation of any public genome sequence
and to identify wrongly annotated submissions. JSpeciesWS will
help to further propagate this approach by providing fast and easy
access to the corresponding analyses and a comprehensive genomes
reference database.
Funding
This research leading to these results has received funding from the European
Community’s Seventh Framework Programme (FP7/2007-2013) under grant
agreement no 311975. This publication reflects t (...truncated)