doesn't seem that difficult. 
$ perl -le 'use strict;use warnings;my($s,@r,@t) = "1 AC2 34 TRP A 6 A
+LA A 7 ILE A 14 GLY A 15";@t=split/\s+/,$s;while((@r=splice @t,0,3)==
+3){print join(" ",@r);}warn"leftovers: @r\n"if @r;'
1 AC2 34
TRP A 6
ALA A 7
ILE A 14
GLY A 15

[download]
what's the catch?

In reply to Re: Split at specific spaces by Anonymous Monk
in thread Split at specific spaces by perl_search_m

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