For datasets like Wallace et al. (2018), GreenGenes are used for taxonomic classification of units (e.g., OTUs). However, in the older GG releases there is not a NCBI taxonomy id associated with each record. If we need to connect SILVA/GG or even Phytozome records (e.g., grass species), we need a function that generates such a mapping between NXBI taxid and Greengenes.
For datasets like Wallace et al. (2018), GreenGenes are used for taxonomic classification of units (e.g., OTUs). However, in the older GG releases there is not a NCBI taxonomy id associated with each record. If we need to connect SILVA/GG or even Phytozome records (e.g., grass species), we need a function that generates such a mapping between NXBI taxid and Greengenes.