I am trying to BLAST many reads against the MaarjAM database (http://maarjam.botany.ut.ee/?action=sTax), a database strictly for arbuscular mycorrhizal fungi sequences. I was able to download the FASTA sequences from the database into a text file and then converted that into a blast-able database using "makeblastdb -in MaarjAM_18s_seq.txt -out MaarjAMdb -dbtype nucl". The main problem is that the headers in the original file are not useful. They look like this:
>gb|AB076274_2004_Saito,_M._GlAc2.1_VTX00166 GGGACATCATGTCGGTCGTGCCTCGGTACGTACTGGTATTGTTGGTTTCTCCCTTCTGACGAACCATGATGTCATTTATT TGGTGTTGTGGGGAATCAGGACTGTTACTTTGAAAA >gb|LN620567_2015_Davison,_J._sp._VTX00311 AGCAGCCGCGGTAATTCCAGCTCCAATAGCGTATATTAAAGTTGTTGCAGTTAAAAAGCTCGTAGTTGAATTTCGGGGTC AGTAGATTGGTCGTGCCACTGGTACGTACTGGTCTTACTGATTCCTCCCTCCTGATGAACTGTAATGCCATTAAT
The headers list out the publication information for the sequence instead of having useful information like the Genus and species names (which is what I need it to say!). I use Blast+ for BLASTing against the NCBI database and it works fine. But using Blast+ for this database is not giving me taxon assignments. Instead, I get alignments with no assignments. Any ideas for fixing this problem easily, without much in the way of new software or package downloads? I am using Linux and I have been using MEGAN to import the blast files. I need to change the headers to provide taxonomic information OR figure out another way to get proper taxon assignments!