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BioPython error parsing standard GenBank file

Dear all,

I've recently resurrected a bioinformatics pipeline I put together a few years ago to load bacterial genome GenBank files into a MySQL database.

Having downloaded *.gbk from the genomes/Bacteria directory on ftp.ncbi.nih.gov, however, I get an error with many of the files:

ValueError: Expected CONTIG continuation line, got:
ORIGIN

It seems that there's an additional CONTIG field immediately before the nucleotide sequence (for example, this occurs with NC_019435.gbk).

Can anyone shed any light on the reason for this error now arising? I don't have any 'old versions' of these files around, but assume that the file format has been modified by GenBank?

many thanks,
Morgan

biopython
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updated by Ram Ram • written by morgan.beeby • morgan.beeby

Standard Genbank file is an oxymoron, there might be an standard but people do what they please with it, it part of its definition.

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written by Raygozak Raygozak

Yeah, but it is an NCBI format so what they do is usually the standard ;)

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written by Peter Peter

2 answers

The GenBank format evolves over time, and newer versions of Biopython cope with this change fine. You appear to have an older copy of Biopython installed.

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written by Peter Peter

I just downloaded NC_019435.gbk.gz from here

and loaded it up in biopython

>>> from Bio import SeqIO
>>> for r in SeqIO.parse("NC_019435.gbk","genbank"):
...     print r.id
...
NC_019435.1

It doesn't seem to have a problem. Perhaps you can share your genbank file and I can have a look?

• 0 views • link
updated by Ram Ram • written by umer.zeeshan.ijaz umer.zeeshan.ijaz

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