Hi Eric,
Thanks for your explanation.
It seems that the max_taxonomic_profile by MetaPhlAn 4.06 does not work for Humann 3.7. Instead, I directly used the taxonomic profile of individual metagenome as the --taxonomic-profile flag for running Humann 3.7 on the corresponding metatranscriptomics data. This method has successfully ran Humann3.7 on mtx data with the provided taxonomic profile by MetaPhlAn 4.06.
Hope this try will help some users to analyze metatranscriptomics data by Humann with taxonomic profile by Metaphlan.
Metatranscriptome analysis with HUMAnN 3.0
Jun