phigaro 2.2.0

Phigaro is a scalable command-line tool for predictions phages and prophages from nucleid acid sequences (including metagenomes) and is based on phage genes HMMs and a smoothing window algorithm.

Phigaro v2.2.0

Requirements

• Python: Python 2.7, Python 3+ versions are supported. pip utility is also required (sudo apt-get install python-pip on Ubuntu).

• Prodigal: Download it from https://github.com/hyattpd/Prodigal/wiki/installation and follow the instructions.

• HMMER: Download it from http://hmmer.org/

• locate: In order to install Phigaro, you need locate. It is present in the latest Ubuntu distributions, but in case you don't have it, install it with sudo apt-get install locate

Installation

pip3 install phigaro --user

then create a config file with:

phigaro-setup

It may take some time, since you are downloading the databases.

Setup Options

Root

By default, root permissions are required for the installation. But you can disable it by adding a flag to phigaro-setup:

phigaro-setup --no-updatedb

All Options

Moreover, you may want to change a path of a config installation file or reconfigurate your Phigaro by adding special flags:

phigaro-setup --help
usage: phigaro-setup [-h] [-c CONFIG] [-p PVOG] [-f] [--no-updatedb]

Phigaro setup helper

optional arguments:
  -h, --help            show this help message and exit
  -c CONFIG, --config CONFIG
                        Path to a config.yml, default is
                        /home/polly/.phigaro/config.yml (default:
                        /home/polly/.phigaro/config.yml)
  -p PVOG, --pvog PVOG  pvogs directory, default is /home/polly/.phigaro/pvog
                        (default: /home/polly/.phigaro/pvog)
  -f, --force           Force configuration and rewrite config.yml if exists
                        (default: False)
  --no-updatedb         Do not run sudo updatedb (default: False)

Manual Setup

Also, you can manually create/change a config.yml file and write the hmmer, prodigal and pvogs paths like it is done in an example below. Other parameters should stay the same for the proper work of Phigaro unless you want to change them on purpose.

For the pvogs you should download all the files to the pvog (or any other folder) via the link unless it wasn't done previously by phigaro-setup.

hmmer:
  bin: /usr/bin/hmmsearch
  e_value_threshold: 0.00445
  pvog_path: /home/user/.phigaro/pvog/allpvoghmms
phigaro:
  penalty_black: 2.2
  penalty_white: 0.7
  threshold_max: 46.0
  threshold_min: 45.39
  window_len: 32
prodigal:
  bin: /usr/local/bin/prodigal

Usage

phigaro -h                                                                                                                                                                          15:04:32
usage: phigaro [-h] [-V] -f FASTA_FILE [-c CONFIG] [-p] [-e EXTENSION [EXTENSION ...]] [-o OUTPUT] [--not-open] [-t THREADS]

optional arguments:
  -h, --help            show this help message and exit
  -f FASTA_FILE, --fasta-file FASTA_FILE
                        Assembly scaffolds\contigs or full genomes
  -c CONFIG, --config CONFIG
                        config file
  -v, --verbose
  -t THREADS, --threads THREADS
                        num of threads (default is num of CPUs)
  -o, --output OUTPUT 
                        output filename for html and txt outputs. Required by default, but not required for stdout only output
  -p, --print-vogs
                        print phage vogs for each region
  --no-html 
                        do not generate output html file
  --not-open 
                        do not open automatically html file
  -e, --extension
                        type of the output: html, txt or stdout. Default is html. You can specify several file formats with a space as a separator. Example: -e txt html stdout
  --not-open
                        do not open html file automatically, if html output type is specified

Running time depends on the size of your input data and the number of CPUs used. The running time for a metagenomic assembly file of 150MB is about 20 minutes.

Output

The output can be annotated prophage genome maps (html) or tabular format (text or stdout).

Test data

Test data is available in test_data folder. In order to run Phigaro on test data, enter the following command from your Phigaro folder:

phigaro -f test_data/Bacillus_anthracis_str_ames.fna -o test_data/Bacillus_anthracis_str_ames.phg -p --not-open

This command generates Bacillus_anthracis_str_ames.phg and Bacillus_anthracis_str_ames.phg.html files in test_data folder. If output file is not specified with -o, the following output is generated:

scaffold        begin   end     taxonomy
NC_003997.3     451613  457261  Siphoviridae
NC_003997.3     460328  482139  Siphoviridae
NC_003997.3     3460450 3482979 Siphoviridae
NC_003997.3     3495703 3505502 Siphoviridae
NC_003997.3     3749518 3776811 Siphoviridae
NC_003997.3     3779698 3784171 Siphoviridae

Methods overview

Open-reading frames (i.e. proteins) are predicted from the input FASTA file using Prodigal. Phage genes are annotated with prokaryotic viral orthologous groups (pVOGs) profile Hidden Markov Models (HMMs), which can be downloaded stand-alone from http://dmk-brain.ecn.uiowa.edu/pVOGs/. Each contig is represented as a sequence of phage and non-phage genes. A smoothing window algorithm (a triangular window function) determines regions with a high density of phage genes and therefore the prophage regions and boundaries, considering the pVOG annotations and the GC content.

Known issues

Phigaro is tested on Linux systems. For MacOS, you may need to add the following softlink ln -s /usr/libexec/locate.updatedb /usr/local/bin/updated and run brew install wget. If you encounter any issues while running Phigaro on test data, please report them to us at [e-mail].

Publication

Elizaveta V. Starikova, Polina O. Tikhonova, Nikita A. Prianichnikov, Chris M. Rands, Evgeny M. Zdobnov, Vadim M. Govorun (2019), Phigaro: high throughput prophage sequence annotation, bioRxiv 598243; doi: https://doi.org/10.1101/598243

(c) E.Starikova, P. Tikhonova, N.Pryanichnikov, 2019