Hi Monks!
So, I have a file like the followind:
236 28KD_MYCLE  Train
MPNRRRCKLSTAISTVATLAIASPCAYFLVYEPTASAKPAAKHYEFKQAASIADLPGEVLDAISQGLSQF
+GINLPPVPSL
TGTDDPGNGLRTPGLTSPDLTNQELGTPVLTAPGTGLTPPVTGSPICTAPDLNLGGTCPSEVPITTPISL
+DPGTDGTYPI
LGDPSTLGGTSPISTSSGELVNDLLKVANQLGASQVMDLIKGVVMPAVMQGVQNGNVAGDLSGSVTPAAI
+SLIPVT
SSSSSSSSSSSSSSSSSSSSSS................................................
+..........
......................................................................
+..........
......................................................................
+......
//
338 A85A_MYCTU  Train
MQLVDRVRGAVTGMSRRLVVGAVGAALVSGLVGAVGGTATAGAFSRPGLPVEYLQVPSPSMGRDIKVQFQ
+SGGANSPALY
LLDGLRAQDDFSGWDINTPAFEWYDQSGLSVVMPVGGQSSFYSDWYQPACGKAGCQTYKWETFLTSELPG
+WLQANRHVKP
TGSAVVGLSMAASSALTLAIYHPQQFVYAGAMSGLLDPSQAMGPTLIGLAMGDAGGYKASDMWGPKEDPA
+WQRNDPLLNV
GKLIANNTRVWVYCGNGKPSDLGGNNLPAKFLEGFVRTSNIKFQDAYNAGGGHNGVFDFPDSGTHSWEYW
+GAQLNAMKPD
LQRALGATPNTGPAPQGA
SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS............................
+..........
......................................................................
+..........
......................................................................
+..........
......................................................................
+..........
..................
//
325 A85B_MYCBO
MTDVSRKIRAWGRRLMIGTAAAVVLPGLVGLAGGAATAGAFSRPGLPVEYLQVPSPSMGRDIKVQFQSGG
+NNSPAVYLLD
GLRAQDDYNGWDINTPAFEWYYQSGLSIVMPVGGQSSFYSDWYSPACGKAGCQTYKWETFLTSELPQWLS
+ANRAVKPTGS
AAIGLSMAGSSAMILAAYHPQQFIYAGSLSALLDPSQGMGPSLIGLAMGDAGGYKAADMWGPSSDPAWER
+NDPTQQIPKL
VANNTRLWVYCGNGTPNELGGANIPAEFLENFVRSSNLKFQDAYNAAGGHNAVFNFPPNGTHSWEYWGAQ
+LNAMKGDLQS
SLGAG
SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS..............................
+..........
......................................................................
+..........
......................................................................
+..........
......................................................................
+..........
.....
//
325 A85B_MYCKA
MTDVSGKIRAWGRRLLVGAAAAAALPGLVGLAGGAATAGAFSRPGLPVEYLQVPSAAMGRSIKVQFQSGG
+DNSPAVYLLD
GLRAQDDYNGWDINTPAFEWYYQSGLSVIMPVGGQSSFYSDWYSPACGKAGCTTYKWETFLTSELPQWLS
+ANRSVKPTGS
AAVGISMAGSSALILSVYHPQQFIYAGSLSALMDPSQGMGPSLIGLAMGDAGGYKASDMWGPSSDPAWQR
+NDPSLHIPEL
VANNTRLWIYCGNGTPSELGGANVPAEFLENFVRSSNLKFQDAYNAAGGHNAVFNLDANGTHSWEYWGAQ
+LNAMKGDLQA
SLGAR
SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS..............................
+..........
......................................................................
+..........
......................................................................
+..........
......................................................................
+..........
.....
//

[download]

and what I want is to print the line with the ID (namely the one that starts with a number), and then, 2 lines, one that will have the sequence of letters and another one that will have the SSSSSSSSSSS....... sequence.
For some reason the code that I have tried does not print anything.
$/="//\n";
while(<>)
{
    if($_=~/^(\d+)\s+(.*)/m)
    {$seq_length=$1; $ID=$2;}

    $seq='';
    while($_!~/([A_z]+)/mg) 
    {  $part1=$1; $seq.=$seq.$part1; } 

     $top='';
    while($_=~/([S\.]+)/mg) {$part2=$1; $top.=$top.$part2;}

    print ">$ID\n$seq\n$top\n";
}
$/="\n";

[download]

In reply to create an one-line format for this by Anonymous Monk

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