Strand specific translation of DNA to aminoacid sequence in PERL

PERL script to read the annotation file and update translated ORF's it into the mysql database and writing it into a multifasta file.

use DBI;

$dbh = DBI->connect('DBI:mysql:meta', 'root', 'password'
) || die "Could not connect to database: $DBI::errstr";

my ($infile) = @ARGV;
open(IN, "$infile");
my $outfile ="multifasta";
open(OUT,">>$outfile");

my $jcvi_read,$strand,$start,$stop,@seq,$ofset,$leng,$wrtseq;

while(my $line = ){
chomp($line);

my @a = split(/ /, $line);
my @c = split(/\s+/, $line);
my @b = split(/\_/, $a[0]);
$jcvi_read=$b[2];
$start = $c[3];
$stop = $c[4];
$strand = $c[6];
$pep = $c[8];


$sth = $dbh->prepare("SELECT sequence FROM metadata WHERE jcvi_read='$jcvi_read'");
$sth->execute();

@seq = $sth->fetchrow_array();

$ofset=$start - 1;
$leng=$stop-$start;
$wrtseq=substr $seq[0], $ofset, $leng;



$sth->finish();

#function to translate DNA to Amino acid based on standard genetic code
sub codon2aa{
my($codon)=@_;
$codon= uc $codon;
my(%genetic_code) = (
'TCA'=>'S', #Serine
'TCC'=>'S', #Serine
'TCG'=>'S', #Serine
'TCT'=>'S', #Serine
'TTC'=>'F', #Phenylalanine
'TTT'=>'F', #Phenylalanine
'TTA'=>'L', #Leucine
'TTG'=>'L', #Leucine
'TAC'=>'Y', #Tyrosine
'TAT'=>'Y', #Tyrosine
'TAA'=>'_', #Stop
'TAG'=>'_', #Stop
'TGC'=>'C', #Cysteine
'TGT'=>'C', #Cysteine
'TGA'=>'_', #Stop
'TGG'=>'W', #Tryptophan
'CTA'=>'L', #Leucine
'CTC'=>'L', #Leucine
'CTG'=>'L', #Leucine
'CTT'=>'L', #Leucine
'CCA'=>'P', #Proline
'CAT'=>'H', #Histidine
'CAA'=>'Q', #Glutamine
'CAG'=>'Q', #Glutamine
'CGA'=>'R', #Arginine
'CGC'=>'R', #Arginine
'CGG'=>'R', #Arginine
'CGT'=>'R', #Arginine
'ATA'=>'I', #Isoleucine
'ATC'=>'I', #Isoleucine
'ATT'=>'I', #Isoleucine
'ATG'=>'M', #Methionine
'ACA'=>'T', #Threonine
'ACC'=>'T', #Threonine
'ACG'=>'T', #Threonine
'ACT'=>'T', #Threonine
'AAC'=>'N', #Asparagine
'AAT'=>'N', #Asparagine
'AAA'=>'K', #Lysine
'AAG'=>'K', #Lysine
'AGC'=>'S', #Serine#Valine
'AGT'=>'S', #Serine
'AGA'=>'R', #Arginine
'AGG'=>'R', #Arginine
'CCC'=>'P', #Proline
'CCG'=>'P', #Proline
'CCT'=>'P', #Proline
'CAC'=>'H', #Histidine
'GTA'=>'V', #Valine
'GTC'=>'V', #Valine
'GTG'=>'V', #Valine
'GTT'=>'V', #Valine
'GCA'=>'A', #Alanine
'GCC'=>'A', #Alanine
'GCG'=>'A', #Alanine
'GCT'=>'A', #Alanine
'GAC'=>'D', #Aspartic Acid
'GAT'=>'D', #Aspartic Acid
'GAA'=>'E', #Glutamic Acid
'GAG'=>'E', #Glutamic Acid
'GGA'=>'G', #Glycine
'GGC'=>'G', #Glycine
'GGG'=>'G', #Glycine
'GGT'=>'G', #Glycine
);


if(exists $genetic_code{$codon}){
return $genetic_code{$codon};

}

else{

return 'X';



}
}
if($strand == '-')
#reverse complementing -ve strands
{$wrtseq=reverse $wrtseq;
$wrtseq=~ tr/ATGC/TACG/;}

my $dna=$wrtseq;
#my $dna="TCATTCTCATTC";
my $protein='';
my $codon3;
for(my $i=0; $i<(length($dna)-2); $i+=3){ $codon3=substr($dna,$i,3); $protein.= codon2aa($codon3); } print $pep."\n"; $dbh->do("INSERT into iddata (jcvi_read,strand,start,stop,protein,orf_id) VALUES('$jcvi_read','$strand','$start','$stop','$protein','$pep')");

print OUT ">".$jcvi_read."|".$pep."\n";
print OUT $protein."\n";
}
$dbh->disconnect();