Wednesday, February 26, 2020

Set up local BLAST site with sequence retrieval function



# Install LAMP package with one liner
sudo install lamp-server^

# enable CGI
sudo a2enmod cgi

# Enable PhP session
vim /etc/php/7.2/apache2/php.ini
# uncomment the line: session.save_path = "/var/lib/php/sessions"
# make sure other lines were setup for session function as described at https://support.qualityunit.com/021373-How-To-Enable-Session-Support-for-PHP
# type ":wq" to save modification and exit vim. If no vim, use other editor like vi or nano.

# edit apache2 config file to enable CGI for specific folder containing NCBI WWWBLAST tools and databases
vim /etc/apache2/sites-enabled/000-default.conf

# add the following lines to the 000-default.conf file
<Directory "/projects/blast_sites">
    Require all granted
    AddHandler cgi-script cgi REAL
    Options Indexes FollowSymLinks ExecCGI MultiViews
    AllowOverride All
</Directory>
</VirtualHost>

# Restart apache2
sudo service apache2 restart

Friday, February 14, 2020

Install QIIME1 with conda 2020


Python 2.7 is gone, but still want to use Qiime1?
conda create -n qiime1 python=2.7
conda activate qiime1
conda config --add channels bioconda
conda install biom-format
pip install qiime

Test
print_qiime_config.py -t

PS:
Guide to install conda or miniconda: https://docs.conda.io/projects/conda/en/latest/user-guide/install/

Galaxy server setup: change to www.your.domain/galaxy



After deploying the local galaxy following the official guide at https://galaxyproject.org/admin/get-galaxy/, a few more steps can be done to hide the port (:8080) and change your galaxy site link to something like www.your.domain/galaxy.


1. Enable apache modules: proxy, proxy_http, and rewrite
sudo a2enmod proxy
sudo a2enmod proxy_http
sudo a2enmod rewrite
2. Add following lines to apache config file, e.g. /etc/apache2/sites-enabled/000-default.conf
RewriteEngine on
RewriteRule ^/galaxy$ /galaxy/ [R]
RewriteRule ^/galaxy(.*) http://localhost:8080$1 [P]
sudo systemctl restart apache2
Done!

PS:
One command to install LAMP server packages on Ubuntu Linux, including Apache, MySQL and PHP. Use the "^" at the end!
sudo apt install lamp-server^

Thursday, February 7, 2019

NGS Assembly related pipeline


What is Minia ? https://github.com/GATB/minia
Minia is a short-read assembler based on a de Bruijn graph, capable of assembling a human genome on a desktop computer in a day. The output of Minia is a set of contigs. Minia produces results of similar contiguity and accuracy to other de Bruijn assemblers (e.g. Velvet).


Version: 2.4 https://github.com/fenderglass/Flye
Flye is a de novo assembler for long and noisy reads, such as those produced by PacBio and Oxford Nanopore Technologies. The core read overlapping algorithm uses A-Bruijn graph to find the mappings between reads and does not require reads to be error-corrected, which resutlts into a faster assembly.

Flye transforms an initial set of draft contigs into a repeat graph. It is somewhat similar to de Bruijn graphs, but can tollerate higher noise level of long reads. Similarly to short read assemblers, Flye maps the original reads back on the graph and uses bridging information to accurately resolve repeats. The package also includes a polisher module, which produces the final assembly of high nucleotide-level quality.



https://github.com/soedinglab/plass
Plass (Protein-Level ASSembler) is a software to assemble short read sequencing data on a protein level. The main purpose of Plass is the assembly of complex metagenomic datasets. It assembles 10 times more protein residues in soil metagenomes than Megahit. Plass is GPL-licensed open source software that is implemented in C++ and available for Linux and macOS. The software is designed to run on multiple cores. Plass was used to create a Soil Reference Catalog (SRC) and a Marine Eukaryotic Reference Catalog (MERC).

Steinegger M, Mirdita M and Soeding J. Protein-level assembly increases protein sequence recovery from metagenomic samples manyfold. biorxiv, doi: doi.org/10.1101/386110 (2018).


Overview of Agalma https://bitbucket.org/caseywdunn/agalma
Agalma is a set of analysis pipelines for transcriptome assembly and analysis, phylogenetic analysis, expression analysis (including phylogenetic analysis of gene expression data). It builds alignments of homologous genes and preliminary species trees from genomic and transcriptome data. Agalma includes support for transcriptome assembly (paired-end Illumina data), and can also import gene predictions from other sources (eg, assembled non-Illumina transcriptomes or gene models from annotated genomes). Please carefully read the details on data requirements before proceeding with your analyses.

Agalma provides a completely automated analysis workflow, and records rich diagnostics. You can then evaluate these diagnostics to spot problems and examine the success of your analyses, the quality of the original data, and the appropriateness of the default parameters. You can then rerun subsets of the pipelines with optimized parameters as needed.

Saturday, January 10, 2015

Where is centromere and short arm on Chimpanzee chromosome 21?

Be careful of the chromosome 21! If you need to work with the problems related to the location of centromeres of chimpanzee.


From the recent chromosome view figures of  from NCBI or UCSC genome browser, you may not found centromere or short arm of chromosome 21 for chimpanzee. Do they have one?  Yes, surely they have.


The short arm and even the centromere were not shown, maybe there are no known genes on the short arm of chromosome 21 of chimpanzee.  Therefore, the 46Mb chromosome 21 were stored in databases as 32Mb length, also viewed as only the long arm (the contig region in the figure above).

NCBI did a well job of documentation, I found this comment very helpful to understand the situation. However, the overall view for these chromosomes is misleading! As a bioinformatician, I should try to avoid such behavior during the data representation.

Finally, another misleading link I found from NCBI:
If you click on the link marked by the red arrow above, you will see chromosome 22, not 21. 


Thursday, February 20, 2014

Wise words from the Star Gate

He was reaching something that was out of reach.
Some might say that make a man great.
Some time it's what we have is more valuable, and it takes a man to recognize it.