#!/usr/bin/perl

# http://perlmonks.org/?node_id=1171851

use strict;
use warnings;

$_ = join '', <DATA>;

1 while s/ ^\w*\K\n(?=\w*\n) | ^.*\..*\K\n(?=.*\.) //mx;

print;

__DATA__
> gi|11SB_CUCMA Train|1 21
MARSSLFTFLCLAVFINGCLSQIEQQSPWEFQGS
EVWQQHRYQSPRACRLENLRAQDPVRLLLPGFSNAPKLIFV
AQGFGIRGIAIPGCAETYQT
SSSSSSSSSSSSSSSSSSSSS....................
...........................
.................
..........
> gi|1A43_HUMAN Train|1 24
MAVMAPRTLVLLLSGALALTQTWAGSHSMRYFYTSVSRPG
RGEPRFIAVGYVDDTQFVRFDSDAASQRMEPRAPWIEQEGPEYWSQTDRANLGTLRGYYNQSEDGSHTIQ
+R
MYGCDVGPDGRFLRGYQQDAYDGKDYIALNEDLRSWTAADMAAQITQRKWETAHEAE
SSSSSSSSSSSSSSSSSSSSSSSS..............................................
+...........................................
.............
..........................................

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In reply to Re: Help in joining these lines by Anonymous Monk
in thread Help in joining these lines by Anonymous Monk

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