Thank you for the suggestion. I used the forward reads for all my samples (which were more than 100).
For the re-seqs.qza file that was generated, they didn't have any link to the ncbi database.
Since I was unable to figure out the problem as my sample sequence quality is variable, I selected a subset of samples, to also reduce the waiting time.
So I used the following commands on the forward reads of the few samples:
qiime dada2 denoise-single
--i-demultiplexed-seqs demuxSE.qza
--o-table tableSE.qza
--o-representative-sequences rep-seqsSE.qza
--o-denoising-stats Dada2SE.qza
--p-chimera-method consensus
--p-trim-left 0
--p-trunc-len 180
--p-n-threads 16
--verbose
Although I think reads don't look bad, but reps-seqs do not have the direct link to ncbi database, which indicates there is an issue in any of my steps.
So this time I used the trunc-q parameter with a score of 20:
qiime dada2 denoise-single \
--i-demultiplexed-seqs demuxSE.qza \
--o-table table22.qza \
--o-representative-sequences rep-seqs22.qza \
--o-denoising-stats Dada.qza \
--p-trunc-len 0 \
--p-trunc-q 20 \
--p-trim-left 5 \
--p-chimera-method consensus \
--verbose
This is what happens:
•R version 3.5.1 (2018-07-02)
•Loading required package: Rcpp
•DADA2: 1.10.0 / Rcpp: 1.0.1 / RcppParallel: 4.4.2
•1) Filtering ......
•2) Learning Error Rates
•50250848 total bases in 369342 reads from 6 samples will be used for learning the error rates.
•3) Denoise samples ......
•4) Remove chimeras (method = consensus)
•5) Report read numbers through the pipeline
•6) Write output
I still got
and
.
I have tried changing The result doesn't change
I also gave a try using paired end reads of these few samples using the commands below:
qiime dada2 denoise-paired \
--i-demultiplexed-seqs demuxtrimmed.qza \
--o-table table.qza \
--o-representative-sequences rep-seqs.qza \
--o-denoising-stats Dada2.qza \
--p-chimera-method consensus \
--p-trim-left-f 6 \
--p-trim-left-r 18 \
--p-trunc-len-f 280 \
--p-trunc-len-r 280 \
--p-n-threads 16 \
--verbose
And this was happening:
•R version 3.5.1 (2018-07-02)
•Loading required package: Rcpp
•DADA2: 1.10.0 / Rcpp: 1.0.1 / RcppParallel: 4.4.2
•1) Filtering ........
•2) Learning Error Rates
•11596776 total bases in 42324 reads from 8 samples will be used for learning the error rates.
•11088888 total bases in 42324 reads from 8 samples will be used for learning the error rates.
•3) Denoise remaining samples ........
•4) Remove chimeras (method = consensus)
•6) Write output
And got this as DADA2 stats and reps-seqs:
I also did a modification of my above commands changing the trunc-len to 230 and even 280, I still get the same problem. Would you be able to direct what problem is going on here? And what can I do here?