Moving Pictures Tutorial Hang-up...


So I am testing out the Moving Pictures Tutorial to familiarise myself with qiime2 and deblur. However, I am running into issues importing my data: I am able to download the barcodes, but I get this response when I try to download the sequences using wget

(qiime2) [email protected] qiime2-moving-pictures-tutorial % wget \
  -O "emp-single-end-sequences/sequences.fastq.gz" \
emp-single-end-sequences/sequences.fastq.gz: No such file or directory

I tried to download the sequences using the browser option instead, but then I ran and got this:

(qiime2) [email protected] qiime2-moving-pictures-tutorial % qiime tools import \
  --type EMPSingleEndSequences \
  --input-path emp-single-end-sequences \
  --output-path emp-single-end-sequences.qza
Usage: qiime tools import [OPTIONS]

  Import data to create a new QIIME 2 Artifact. See
  for usage examples and details on the file types and associated semantic
  types that can be imported.

  --type TEXT             The semantic type of the artifact that will be
                          created upon importing. Use --show-importable-types
                          to see what importable semantic types are available
                          in the current deployment.                [required]
  --input-path PATH       Path to file or directory that should be imported.
  --output-path ARTIFACT  Path where output artifact should be written.
  --input-format TEXT     The format of the data to be imported. If not
                          provided, data must be in the format expected by the
                          semantic type provided via --type.
  --show-importable-types Show the semantic types that can be supplied to
                          --type to import data into an artifact.
                          Show formats that can be supplied to --input-format
                          to import data into an artifact.
  --help                  Show this message and exit.

                    There was a problem with the command:                     
 (1/1) Invalid value for '--input-path': Path 'emp-single-end-sequences' does
  not exist.

I think my issue is a quick fix of properly getting the data and naming it accordingly ... but I am confused, haha.

Thanks in advance for your support!

Hi @Taylorr,

Thanks for reaching out! Happy to lend a hand here :wave:t3:

Based on your second code block, it seems like the emp-single-end-sequences directory doesn't exist locally on your machine (at least in your working directory where you're running those commands). Let's try wget again, and then have you run the rest of the subsequent commands after that's working.

Were you able to run the other wget commands successfully, or did you have this issue with all of them? The command itself looks correct, so there might be an issue with your conda environment.

Cheers :lizard:

Hello @lizgehret !

Thank you so much for following up with me on this.
After running the wget command again, as you suggested, I had success! Although, I do have remaining questions, mainly concerning data input/output.

If I try to run my own data through deblur using qiime2, how might I change the paths in the following commands?

qiime tools import \
  --type EMPSingleEndSequences \
  --input-path emp-single-end-sequences \        
  --output-path emp-single-end-sequences.qza

Also, are the input files .fastq ?

qiime deblur denoise-16S \
  --i-demultiplexed-seqs demux-filtered.qza \
  --p-trim-length 120 \
  --o-representative-sequences rep-seqs-deblur.qza \
  --o-table table-deblur.qza \
  --p-sample-stats \
  --o-stats deblur-stats.qza

Lastly, do I need to change the demux command when demultiplexing if my data is not associated with Earth Microbiome Project?

Thank you for your support!
Taylor x


Okay, I tried to execute the following:

% qiime tools import \
--type EMPSingleEndSequences \
--input-path trail1stock\                   ; name of directory that has my fastq file
--output-path trail1stock-seq.qza

And got this error:

I think I might have messed up with the output path perhaps, but I am not really sure. I've done some googling but haven't come up with anything.
Do you see what might be the issue?


Hi @Taylorr,

It looks like you're missing a space between your input path name and the line break, which is why QIIME 2 thinks your input path name is trail1stock--output-path, and that you're missing the --output-path parameter.

You can copy/paste this adjusted command below, and it should work for you:

qiime tools import \
--type EMPSingleEndSequences \
--input-path trail1stock \
--output-path trail1stock-seq.qza

Cheers :lizard:

Perfect! That fixed it ... almost.
So now I am dealing with a few issues related to the EMPSingleEndSequences type.
I tried to run with the (your) code above, but got:

There was a problem importing trail1stock:
Missing one or more files for EMPSingleEndDirFmt: 'sequences.fastq.gz'

So I tried to rename my data files but then:

There was a problem importing trail1stock:

  trail1stock/sequences.fastq.gz is not a(n) FastqGzFormat file:

  File is uncompressed

Which makes sense. Do you know how to solve this issue - either by re-routing EMPSingleEndSequences to take my original file or by some other means?

Thank you for your support!!

Hi @Taylorr,

Apologies for the delay in response on this!

Take a look at our importing guide for EMPSingleEndSequences, and make sure that your data is in the format described there. If that is all in order, the only issue is (as you mentioned in your previous response) related to this error:

If your files are not compressed (i.e. zipped), they will not be accepted. Simply adding .gz to the end of your filename will not solve this - file extension names don't mean anything unless the data format reflects what that extension should represent.

You'll need to run the gzip command on both your sequences and barcodes files in order to create the correct compressed file format (which will result in the sequences.fastq.gz and barcodes.fastq.gz files that are required). Here's an example of what that command looks like on OSX:

gzip sequences.fastq

Hope this helps! Cheers :lizard: