#! perl -slw
use strict;

$/ = "\n>"; # set record separator

while( <DATA> ){
	# Split the record in two
	my( $label, $data ) =  m[ (^ [^\n]+ ) \n ( .*$ ) ]sx;
	
	# Remove extraneous '>' characters
	$label =~ s[^>][];
	$data =~ s[>$][]s;
	
	# remove newlines from the data
	$data =~ tr[\n][]d;
	
	# count the characters
	# my $count = $data =~ tr[ACGT][ACGT]; # Corrected the omission of $data from this line.

	my $count = $data =~ tr[ACGT][ACGT];
	
	print "$label contains $count characters";
}

=output

P:\test>321523
gb|AE008689|:2073051-2073458, Atu4895 contains 408 characters
gb|AE008689|:c2074151-2073549, Atu4896 contains 603 characters
gb|AE008689|:c2074749-2074345, Atu4897 contains 405 characters

=cut


__DATA__
>gb|AE008689|:2073051-2073458, Atu4895
TTGGTCACATATTTTCGCTATTCGAAACCCAAATATCCCTGCGGAACACGTTTTATTGGAGCCGCCGTTT
TGCAGTTGCTCGGTGCTGGATTCTTGGCGTTCGTCTTTTGTCTGCTGGATGGGCTCACTGCAAAACCAAC
GATAATTCTCGGTCAGTTTGTATCATGCCTAGTGGGGAGCGTCGCCGGCTTTCATTTCGTGGCTTTTCGT
CGCCCAGGCACGGACGGCCAACTTTACCTTATCGCGACGTCGCTCTTGGCATTTGGGACCCATTATTGGC
TGGTGTCATATTCATTACCTGACCTTTTGCTAGCAAGATTGATTTCAGGATTTGGATCGGGTGTGGTTGT
TGCAGGAACTTTCCGACGTCGCTTTCTGGAAAATCCGGTAATTCCCTGCGTTCGATAG
>gb|AE008689|:c2074151-2073549, Atu4896
GTGTTTGGACCATATTTTCTGTGCAAACTAAACGATGACATAGGGCGATTTTTAGTGGCGGACAAATACA
GACTTCCCGAAGAGTTTTTTACCACTCGGTTTCTCGTTAGACGCATCGTACCCACAGACGCTGAAGCTAT
TTTCGAAGGGTGGAACACCGATCCCGAGGTGACGAAGTACCTGACGTGGAAACCCCACTCCGAGCTTGGC
CAGACACAGCGGGCGATTGAAGAAAATTATAGTGCGTGGAATGCAGGTACATCGTTTCCAGCTGTCATCT
GCCATCGCGAACGGCCACATGAACTAATCGGCCGTATTGATGCACGTCCGATGGGCCACAAGGTCTCTTA
CGGGTGGCTTGTCCGAAGAACCTGGTGGGGCCGGGGTGTTGCAAGCGAGGTCGTTCAACTCGCTGTAGAA
CACGCGTTATCGCATCCGCGCATCTTTCGCACCGAAGCATCCTGCGACGTTCTGAACACGGCGTCAGCAA
GAGTGATGGAAAAAGTAGGGATGACAAAGGAGGCCGTGCTTCGACGGTACCTTTTTCACCCCAATTTTTC
GAATATGCCGCGAGACGCCTTCCTGTATTCCAAGGTACGTTAA
>gb|AE008689|:c2074749-2074345, Atu4897
ATGAAACATACCATCGCAGTTCTCGGCCTGATCACCTTCTCCAGCCCGGCCTTCGCAGCATCGTGCGAGA
AAAACTTCACCGTCTCAGGCGTACCGATGGTCACGGCTGTCTCTTACAAATCCTTTCAGGAACTGCCGAA
AGCCAAAGCACCAGCTGTCCTTCAAAAGCTCGCCCAGGCCGTCGCGGCAGAAGGTTTTTCAGGTATCCAG
ATCAACAAGGCACTGTCGTCAATCGATGCCCATCAGGAAACCAGCGGAAGTGGCAGGATTCAGACGCTGC
GGGTTGTCGCCCGCCAGAAAGGCGCCGCTGTCCGGATCGATGCTGTCTTCAATATTCAGGCAGGACAGAT
CGCCGACAAAGACGTCATCCGCAAGGGCATCTGCGACATCATAAAAGGCGCGTAA