【求助】如何获取genbank中est序列?

【求助】如何获取genbank中est序列?
我有一段程序是从NCBI根据gi编号下载EST序列的,但是如果我想根据克隆文库名称或Organism下载,如何修改下面的程序啊?
#!/usr/bin/perl -w

use Bio::DB::GenBank;
use Bio::SeqIO;
my $gb = new Bio::DB::GenBank;

print "Please enter output file including suffix:";
chomp(my $ou=<STDIN>);
open(OUT,">$ou")||die "Can't open the file!";

my $seqout = new Bio::SeqIO(-fh => \*OUT, -format => 'fasta');
my $seqio = $gb->get_Stream_by_id([ qw(88888 99999))]);
while( defined ($seq = $seqio->next_seq )) {
$seqout->write_seq($seq);
}

希望大家相互交流学习帮助

把名字转化下了…….