file1:
TST_01  sp|123|fts
TST_02  sp|3438|rvs
TST_03  sp|2744|rtp

file2:
file1:
sp|123|fts  checked_proved
sp|3438|rvs  proven_right
sp|2744|rtp  un_proved

desired result file:
TST_01  sp|123|fts  checked_proved
TST_02  sp|3438|rvs  proven_right
TST_03  sp|2744|rtp  un_proved

##</code><code>##

#!/usr/bin/perl
open(FH1,file1.txt);
open(FH2,file2.txt);
@array=<FH2>;

while($var=<FH1>){
  ($first,$second)=split("\t",$var);
  @grepped= grep ("$second",@array);
  print "$first\t@grepped\n";
}