compile : perl prog.pl input.db result 

#!/usr/bin/perl
my $input = $ARGV[0];
my $output = ">" . $ARGV[1];
my $counter=1;
my $no='D000001';

open(INPUT, $input) or die "Can't open $input.";
open(OUTPUT, $output) or die "Can't open $output.";

$/="//\n";
while (<INPUT>) {
    print "DBACC\t $no\n";
    if ($_=~/^DATE\s*(.*-.*-.*)\s*\n/){
        print "DATE\t $1\n";}
    elsif ($_=/^GenBank:(.*),\sEMBL:(.*),\sDDBJ:(.*)},\sSwissProt:(.*)\n/){
    print "ACCESSION:GenBank\t ($1)\n";
    print "ACCESSION:EMBL\t ($2)\n";
    print "ACCESSION:DDBJ\t ($3)\n";
    print "ACCESSION:SwissProt\t ($4)\n";
    }
    print "Entry $counter\n";
    $counter++;
    $no++;
   }
close (INPUT);
close (OUTPUT);