DB<6> $p = 'ALTAMCMNVWEITYHKGSDVNRRASFAQPPPQPPPPLLAIKPASDASD';

  DB<7> @b = split /[KR](?!P)/, $p;

  DB<8> x \@b;
0  ARRAY(0x6004f0f88)
   0  'ALTAMCMNVWEITYH'
   1  'GSDVN'
   2  ''
   3  'ASFAQPPPQPPPPLLAIKPASDASD'

##</code><code>##

  DB<10> p $p
ALTAMCMNVWEITYHKGSDVNRRASFAQPPPQPPPPLLAIKPASDASD
  DB<11> $p = 'ALTAMCMNVWEITYHKGSDVNRRASFAQPPPQPPPPLLAIKPASDASD';

  DB<12> $p =~ s/([KR])(?!P)/$1=/g;

  DB<21> p $p
ALTAMCMNVWEITYHK=GSDVNR=R=ASFAQPPPQPPPPLLAIKPASDASD