Biopython

The Biopython team is pleased to release Biopython 1.56, almost exactly three months after our last stable release ( Biopython 1.55).

The Bio.SeqIO module has been updated to support protein EMBL files (used for the patents database), IMGT files (a variant of the EMBL file format, with help from Uri Laserson), and UniProt XML files (thanks to Andrea Pierleoni). Also the SeqFeature object gained some new methods, and the Bio.Seq translation function can now be used with an arbitrary genetic code.

This is a reminder that the forthcoming Biopython 1.56 release is planned to be our last release to support Python 2.4.

Looking back, we supported Python 2.3 for about six years - it was released July 2003, and Biopython 1.50 released in April 2009 was the last to support it. Similarly, Python 2.4 was released six years ago (November 2004).

Dropping Python 2.4 support will allow use to assume standard library modules like the ElementTree XML parser and SQLite 3 support will be available. There are also several new language features in Python 2.5+ which will be useful, and it should make supporting Python 3 a little easier as well.

The Biopython team is proud to announce Biopython 1.55, a new stable release, about three months after our last stable release ( Biopython 1.54) and the beta release earlier in August.

A lot of work has been towards Python 3 support (via the 2to3 script), but unless we broke something you shouldn’t notice any changes ;)

In terms of new features, the most noticeable highlight is that the command line tool application wrapper classes are now executable, which should make it much easier to call external tools. This is described in the updated documentation.

We’ve just released a beta of Biopython 1.55 for user testing.

Since Biopython 1.54 was released three months ago, we’ve made a good start on work for Python 3 support (via the 2to3 script), but as a side effect of this we’ve had to update quite a lot of the older parts of the library. Although the unit tests are all fine, there is a small but real chance that we’ve accidentally broken things - which is why we’re doing this beta release.

The Biopython team is proud to announce Biopython 1.54, a new stable release of the Biopython library. Biopython 1.54 comes five months after our last release and brings new features, tweaks to some established functions and the usual collection of bug fixes.

This is the first stable release to feature the new Bio.Phylo module which can be used to read, write and take data from phylogenetic trees in Newick, Nexus and PhyloXML formats. The module is the result of Eric Talevich’s Google Summer of Code project which was supported by The National Evolutionary Synthesis Center (NESCent).

In another quirk to the FASTQ story, recent Illumina FASTQ files don’t actually use the full range of PHRED scores - and a score of 2 has a special meaning, The Read Segment Quality Control Indicator (RSQCI, encoded as ‘B’).

Hats off to Dr Torsten Seemann for raising awareness of this issue in his post on the seqanswers.com forum, referring to a presentation by Tobias Mann of Illumina which says:

The Read Segment Quality Control Indicator:

[Read More]

This is another blog post to highlight one of the neat tricks you’ll be able to do with Biopython 1.54 (which you can help test with the Biopython 1.54 beta release).

It is often useful to be able to extract a few records from a larger sequence file - for example, some sequences of interest from a full UniProt or GenBank dump. One obvious way to try to do this is to parse the file into an object representation (i.e. SeqRecord objects using Bio.SeqIO.parse(...)), filter to pick out the entries you want, and then write them back to disk (using Bio.SeqIO.write(...)). However, for complex file formats like GenBank this can be lossy ( Bio.SeqIO does not support a 100% identical round trip), and Biopython don’t currently support writing out the SwissProt plain text format used by UniProt. So, that approach won’t work.

One of the small changes coming in Biopython 1.54 (which you can try out already using the Biopython 1.54 beta) is to Bio.SeqIO and Bio.AlignIO. Previously the input and output functions had required file handles, but they will now also accept filenames.

This is a case of practicality beats purity (to quote the Zen of Python), and is particularly handy when doing very short scripts or working at the Python prompt.

For example, filtering a FASTA file to take only entries with a minimum length of 100 can be done like this (with handles):

A beta release for Biopython 1.54 is now available for download and testing.

Since Biopython 1.53 was released at the end of last year, several new features and more documentation have been added, plus the usual bug fixes. For full details see the NEWS file.

All the new features have been tested by the dev team but it’s possible there are cases that we haven’t been able to foresee and test, especially for the updated multiple sequence alignment object (which is what you’ll now get when parsing alignments with Bio.AlignIO), the new Bio.Phylo module, and the Bio.SeqIO support for Standard Flowgram Format (SFF) files.

I’m delighted to announce an open access publication in Nucleic Acids Research describing the FASTQ file format based on the conventions agreed by the OBF projects:

The Sanger FASTQ file format for sequences with quality scores, and the Solexa/Illumina FASTQ variants Peter J. A. Cock ( Biopython), Christopher J. Fields ( BioPerl), Naohisa Goto ( BioRuby), Michael L. Heuer ( BioJava) and Peter M. Rice ( EMBOSS). Nucleic Acids Research, doi:10.1093/nar/gkp1137

This will hopefully serve as a reference describing the original standard Sanger FASTQ, and the two variants from Solexa/Illumina, and how to inter-convert between them.