Formatting database for BLAST

Unformatted databases can be downloaded from ftp://ftp.ncbi.nlm.nih.gov/blast/db/FASTA/, while formatted ones from ftp://ftp.ncbi.nlm.nih.gov/blast/db/.
Command to use to format a database:
formatdb -i input_db -p F -o T for nucleotide
formatdb -i input_db -p T -o T for protein

For yeast.nt use: formatdb -i yeast.nt -p T -o T
For nr use: formatdb -i nr -p T -o T