[EMBOSS] getorf includes unspecified amino acids as part of the ORF sequence

[Fungazid]

Hello people,

I just installed emboss on linux ubuntu (using the ubuntu synaptic package manager). I am using the getorf program, and I see it gives me this kind of output lines:

>00001_3 [803 - 1120] 
LARLRFVVLGNSFIASAKGWSTPYGPTTFGPFRSCIYPRVFRSTRVRKAMATRIGSNRVN
ILIRCTXXXXXXXXXXXXXXXXXXXXXXXXXNPYLGWWCYIFCIFR 

I don't like the Xs as they represent unspecified amino acids. Is there an input parameter to tell the program to report only the regions before and after the Xs ?

In addition (and maybe this is beyond the scope of this mailing list) what is the biological meaning of such Xs ?


thanks,
Avi