The GBFF file is a compressed file of many GenBank format files and consists of two files.

One is a sequence file in fna format.

The other is a definition file in gbff format (without sequence).

(Note that the older format GBFF file was a collection of regular GenBank format files with one definition part and one sequence part.

The way to load GBFF files into the IMC is as follows.

Use "Multi GenBank File Expander" to expand the two compressed files into a taxonomy tree-like directory and make that directory the IMC's root directory.

For details on how to do this, please click here.