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cutadapt: error: unused arguments //not recognizing my sequences when using a loop?

Hi all-- I'm fairly new at bioinformatics--I can usually find my way around errors (with the help of forums like these!)--but so far I have not been successful.

I'm running cutadapter through a Conda environment--and I have multiple primer sequences I am trying to remove. I've created a for loop for my primers here:

for i in *_R1_001.fastq.gz
do
  SAMPLE=$(echo ${i} | sed "s/_R1_001\.fastq\.gz//") 
  echo ${SAMPLE}_R1_001.fastq.gz ${SAMPLE}_R2_001.fastq.gz
cutadapt -g CTTGGTCATTTAGAGGAAGTAA -g CTTGGTCATTTAGAGGAAGTAA -g CTTGGTCATTTAGAGGAACTAA -g CCCGGTCATTTAGAGGAAGTAA -g CTAGGCTATTTAGAGGAAGTAA g- CTTAGTTATTTAGAGGAAGTAA -g CTACGTCATTTAGAGGAAGTAA -a GCATCGATGAAGAACGCAGC -a CCATCGATGAAGAACGCAGC -a GCATCGATGAAGAACGTAGC -a ACATCGATGAAGAACGCAGC -a ACATCGATGAAGAACACAGT -a GCAACGATGAAGAACGCAGC -a GCATCGATGAAGAACGC -G GCTGCGTTCTTCATCGATGC -G GCTGCGTTCTTCATCGATGG -G GCTACGTTCTTCATCGATGC -G GCTGCGTTCTTCATCGATGT -G ACTGTGTTCTTCATCGATGT -G GCTGCGTTCTTCATCGTTGC -G GCGTTCTTCATCGATGC -A TTACTTCCTCTAAATGACCAAG -A TTACTTCCTCTAAATGACCGAG -A TTAGTTCCTCTAAATGACCAAG -A TTACTTCCTCTAAATGACCGGG -A TTACTTCCTCTAAATAGCCTAG -A TTACTTCCTCTAAATAACTAAG -A TTACTTCCTCTAAATGACGTAG -n 2 --cores 4 -o ${SAMPLE}_R1_001.cut.fastq.gz -p ${SAMPLE}_R2_001.cut.fastq.gz ${SAMPLE}_R1_001.fastq.gz ${SAMPLE}_R2_001.fastq.gz
done

When I run

sh cutadapt.paired.used.sh

I get the following error over and over for all of my samples:

cutadapt: error: unrecognized arguments: CA18-REP1_S19_L001_R1_001.fastq.gz CA18-REP1_S19_L001_R2_001.fastq.gz
CA18-REP2_S20_L001_R1_001.fastq.gz CA18-REP2_S20_L001_R2_001.fastq.gz
Run "cutadapt --help" to see command-line options.
See https://cutadapt.readthedocs.io/ for full documentation.

I've tried running the code on one sample (instead of all of them at once in a loop) and I get similar results:

cutadapt --pair-adapters -g CTTGGTCATTTAGAGGAAGTAA -g CTTGGTCATTTAGAGGAAGTAA -g CTTGGTCATTTAGAGGAACTAA -g CCCGGTCATTTAGAGGAAGTAA -g CTAGGCTATTTAGAGGAAGTAA g- CTTAGTTATTTAGAGGAAGTAA -g CTACGTCATTTAGAGGAAGTAA -a GCATCGATGAAGAACGCAGC -a CCATCGATGAAGAACGCAGC -a GCATCGATGAAGAACGTAGC -a ACATCGATGAAGAACGCAGC -a ACATCGATGAAGAACACAGT -a GCAACGATGAAGAACGCAGC -a GCATCGATGAAGAACGC -G GCTGCGTTCTTCATCGATGC -G GCTGCGTTCTTCATCGATGG -G GCTACGTTCTTCATCGATGC -G GCTGCGTTCTTCATCGATGT -G ACTGTGTTCTTCATCGATGT -G GCTGCGTTCTTCATCGTTGC -G GCGTTCTTCATCGATGC -A TTACTTCCTCTAAATGACCAAG -A TTACTTCCTCTAAATGACCGAG -A TTAGTTCCTCTAAATGACCAAG -A TTACTTCCTCTAAATGACCGGG -A TTACTTCCTCTAAATAGCCTAG -A TTACTTCCTCTAAATAACTAAG -A TTACTTCCTCTAAATGACGTAG -n 2 --cores 4 -o SK03_S36_L001_R1_001.cut.fastq.gz -p SK03_S36_L001_R2_001.cut.fastq.gz SK03_S36_L001_R1_001.fastq.gz SK03_S36_L001_R2_001.fastq.gz

Produces the following

cutadapt: error: unrecognized arguments: SK03_S36_L001_R1_001.fastq.gz SK03_S36_L001_R2_001.fastq.gz

I'm not sure what I'm doing wrong? Any help would be much appreciated!

Thnx

cutadapter

For starters, are you sure that you can't use ambiguous codes instead of all those nearly identical -g's?

1 answer

Code has a typo: g- CTTAGTTATTTAGAGGAAGTAA. Please fix that

That was definitely the problem. Thank you!

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