If I understood your question clearly, here is my solution. You can use negative look behind regex and split function to accomplsh it. TIMTOWTDI.

$string = 'APADPKGSTIDRPDAARTLTVHKCEQTDTRGVKEGTRNEDPQAECKPVSDVEFTITKLN
+VD';

@arr = split /(?<!P)(K|R)/, $string;

print @arr;


output:
-------

APADPKGSTIDRPDAARTLTVHKCEQTDTRGVKEGTRNEDPQAECKPVSDVEFTITKLNVD

[download]

Take a look at perlre and split function.

Prasad

In reply to Re: cleaving a sequence with specific alphabets by prasadbabu
in thread cleaving a sequence with specific alphabets by heidi

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