I am a beginner with Blast+.I am using Windows.My aim as of now is to download the nr protein sequence in Fasta format and then format it using makeblastdb.then extract the first 1000 characters from the nr file as a seperate file (say qa.fasta) and then query it against the whole database.
Now i downloaded the nr database in Fasta format from this link
ftp://ftp.ncbi.nlm.nih.gov/blast/db/FASTA/nr.gz (are these the original fasta files??)
then i used to makeblastdb command like this
makeblastdb -in nr -dbtype prot -out outnr -> This resulted in the nr file to be split into different parts nr.00 to nr.03.(Is this normal).
Now i need help to extract the first 1000 char from nr file.But how to i open a Fasta file in windows??? How do i proceed??