I recently ran into a problem with the taxaonomy.qza artifact when working with Qiime2-2018.8 and the Silva 132 99% 16S OTUS.
CategoricalMetadataColumn does not support values with leading or trailing whitespace characters. Column ‘Taxon’ has the following value: ‘D_0__Bacteria;D_1__Bacteroidetes;D_2__Ignavibacteria;D_3__OPB56;D_4__uncultured bacterium ’
I tried to filter this entry with qiime taxa filter-table, but this command threw basically the same error. I eventually opened the Silva taxonomy file and removed the offensive white space in the original file and then retrained the classifier. This worked, but it takes a lot of time to remake classifiers.
I googled the error and found that it was previously reported (Qiime taxa filter-table error), but the issue was closed in June.
I just wanted to let you know this is still a problem.
Best wishes and thanks for all your hard work
Maggi
Thanks for the report @Maggi_Mars --- we still haven't gotten around to addressing the trailing whitespace issue. As well, I wouldn't put too much stock in the forum topic being closed --- all forum topics automatically close after 30 days of activity, but the developer issue xrefed there is still going strong: