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  • AncientGenomes
    Junior Member
    • Jul 2017
    • 1

    MALT/MEGAN question

    Hello all,

    I'm trying to use MALT/MEGAN for the first time through ubuntu. I have a FASTA file of some shotgun microbial sequences that I converted from an Illumina HiSeq FASTQ output and I'm trying it to run these through the examples in the MALT manual locally on my machine. MALT is properly installed universally, as is MEGAN.

    Here's my command line for malt-build:

    malt-build -i ./Viral_Reference/viral.1.1.genomic.fna.gz -d index -a2taxonomy ./nucl_acc2tax-May2017.abin -s DNA

    I then did the following:
    malt-run -i 05C_test.fasta -d ./index -m BlastN -o .

    it says it's coming back with 10,440 queries, 11 aligned queries and 22 num. alignments. This all seemed to work fine and produced the necessary tree and mapping files.

    after doing this in the command line:
    MEGAN -g -f ./05C_test.rma6 -E

    I'm getting the following:

    Executing: load treeFile='ncbi.tre';
    Loading mapping file: ncbi.map
    Reading file: ncbi.map: 1266115
    Loading taxonomy file: ncbi.tre
    Reading file: ncbi.tre: 1266115
    Executing: open file='./05C_test.rma6';
    Alert - Open file failed: java.io.IOException: File has unknown type: ./05C_test.rma6

    It seems this is an issue with the rm6 output format. My java is up to date-1.8.0_131. I don't think it is an input problem either.

    One additional question:
    I can't seem to use -f to get an output of Tab or Text. it's giving me a kickback the -f and --format are not functional. is this a problem other users have experienced?

    Thank you very much,
    AG

    UPDATE 7/26/17:
    Looks like this is an issue with Ubuntu version of MEGAN not being compatible with .rma6 extension files. I opened the file just fine on the Windows 64bit version of MEGAN. I've alerted the developers about this issue.

    Anyone else using MALT here?
    Last edited by AncientGenomes; 07-26-2017, 09:27 AM. Reason: Compatibility issue identified
  • mbravo
    Junior Member
    • Nov 2017
    • 1

    #2
    different problem

    Hi,
    I´m using MALT for the first time too and I have some doubts about building the index.
    My command line for malt-build is :

    malt-build -i /mnt/Archives/BLAST_databases/nt/*.* -d Index -a2taxonomy /mnt/Cromosoma/mavila/mbravo/malt/data/gi_taxid-March2015X.bin --sequenceType DNA

    It creates the following files:
    index0.idx ref.idx table0.db table0.idx

    but they`re empty.

    I will appreciate any comment.

    Comment

    • Sama
      Junior Member
      • Mar 2018
      • 1

      #3
      Hi,

      @mbravo , maybe the files are empty because you are using a gi_taxid table instead of an acc_taxid table in the parameter "-a2taxonomy /mnt/Cromosoma/mavila/mbravo/malt/data/gi_taxid-March2015X.bin".

      Comment

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