I’m using the version 2018.11.0 of qiime2, installed with conda, and I tried to extract reads, for training purposes, with the plugin “feature-classifier” from the Silva 16S database v132.
Before writting all the steps I went into, I would like to ask you whether it makes sense to get the following error
RuntimeError: No matches found
when I’m using the following primers for extracting reads for the 16S V3-V4 region:
forward primer: TCGTCGGCAGCGTCAGATGTGTATAAGAGACAGCCTACGGGNGGCWGCAG reverse primer: GTCTCGTGGGCTCGGAGATGTGTATAAGAGACAGGACTACHVGGGTATCTAATCC
whereas I do not get any error when I’m trying to extract reads with the following primers:
forward primer: GTGCCAGCMGCCGCGGTAA reverse primer: GGACTACHVHHHTWTCTAAT
The error has also been replicated by using an older qiime2 version (2018.2.0) and also after lowering the parameter “–p-identity” to 0.7.
The first primers have been used successfully in Illumina MiSeq 16S sequencing.
Thanks in advance for any help.