I am a newbie to gene ontology enrichment analyses and would really appreciate any help. I recently annotated several bacterial genomes using RAST. RAST outputs a number of annotation files including a GFF3 file and a gtf file, but I do not know how to map the annotations from these files to gene ontology classifications. For instance, within the last column of the gtf file, some of the genes are labelled with an EC number, some genes with a TC number and the majority of genes have some putative annotated function, but no associated mapping number. Is there a standard way to map the output from the gtf file to GO terms?