I have a data like this: 
line=ULMNm  3  1fdy_07      N-ACETYLNEURAMINATE LYASE           user  
+ 1           3                                                     
  RMSD =     1.06 A
  MATRIX:   -0.3862 -0.2080 -0.8987  0.6457  0.6347 -0.4244 -0.6587  0
+.7442  0.1108   -16.917   -91.429   -35.632  
                   D  47    SER       A  57    SER.?     
                   D  48    THR       A  56    THR.?     
                   D 165    LYS       A  33    LYS~?     
 
line=ULMNm  3  2tmd_00      TRIMETHYLAMINE DEHYDROGENASE        user  
+ 1           3                                                     
  RMSD =     1.15 A
  MATRIX:    0.9011 -0.4313  0.0445 -0.1032 -0.3130 -0.9441 -0.4211 -0
+.8462  0.3266    52.913    23.262    25.449  
                   A 169    TYR       A  41    TYR~?     
                   A 172    HIS       A  95    HIS^?     
                   A 267    ASP       A  98    ASP~?

[download]
I'd like to store everything starting from 'line=ULMNm' till before the next 'line=ULMNm' as one string. Previously, I always used to define the input line separator ($/) like this: 
$/ = "     
 
";

[download]
to make the script read multiple lines instead of line by line.

However, if I want to read another text file line by line in the same perl script, redefining $/ = "\n" doesn't work. I'm really bad with regex (and have no idea how exactly to get good at it, it baffles me how you guys can be so good). Could you tell me how to do this?

In reply to regex question: store multiple lines as a string by nurulnad

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