BioPHP - Salt_Adjusted Melting Temperature (Tm) Calculations

Original code submitted by joseba
Code bellow is covered by GNU GPL v2 license.

Description

Last change: 2010/10/18 17:04 | Edit description | Recent Changes | Original description

Salt_Adjusted Melting Temperature (Tm) Calculations
$salt: monovalent cations concentration([K+] + [Na+]), mM

Code

Last change: 2010/10/18 17:04 | Edit Code | Recent Changes | Download | Original code

function Salt_Adjusted_Tm($seq,$salt){
 $seq_len=strlen($seq);
 $n_CG=substr_count($seq,"G");
 if ($seq_len > 0) {
     $cg=100*$n_CG/$seq_len;
     return round(81.5+16.6*log10($salt/1000)+0.41*$cg-675/$seq_len,1);
                }
}