Member Site › Forums › Rosetta 3 › Rosetta 3 – General › Native gives higher (positive) than lowest energy and clustered decoys
- This topic has 6 replies, 2 voices, and was last updated 13 years, 4 months ago by Anonymous.
-
AuthorPosts
-
-
June 2, 2011 at 2:19 pm #930Anonymous
Hi,
My native structure gives higher (positive) energy than lowest energy and clustered decoys (170 vs -77) with an output of 40000 decoys using abnitiorelax app.
The protein is an all beta-sheet and small (40 aa). From papers i`ve read and looking at the hydrogen bond terms at the rosetta energy function, i know it isn`t very good
at modeling this kind of proteins. I`m going to try it anyway. Any ideas why this happens? What am i doing wrong?Thanks for the help,
Tiago
-
June 2, 2011 at 3:53 pm #5687Anonymous
It’s known that structures from the PDB, when scored directly with the Rosetta energy function, can give ludicrously high energies. The reason is that Rosetta is sensitive to small positional differences. (e.g. if two atoms are slightly closer than they should be – we’re talking fractions of an Angstrom – the VDW repulsive energy can shoot way up.)
It’s highly recommended to either minimize the structure (or use the regular relax application) in the Rosetta energy function prior to comparing energies between native and predicted structures.
-
June 2, 2011 at 4:01 pm #5688Anonymous
Using the idealize application or the relax application?
Thanks -
June 3, 2011 at 9:04 am #5705Anonymous
Thank you very much for your time.
Tiago
-
June 3, 2011 at 3:16 pm #5710Anonymous
I´m assuming that relax uses scores12. For comparing the native score against decoys, generated with abinitio, the score weights should be the same.
Are they, in the default option, the same for relax and abinitiorelax?thank you
Tiago
-
June 2, 2011 at 10:43 pm #5698Anonymous
The idealize application is more to change bond distances and angles to their “ideal” settings.
The relax application (http://www.rosettacommons.org/manuals/archive/rosetta3.2.1_user_guide/app_relax_command.html) would likely be your best bet. To keep the backbone from moving too much, you can add the flag “-constrain_relax_to_start_coords” to the command line.
By the way, you might also be interested in http://www.rosettacommons.org/manuals/archive/rosetta3.2.1_user_guide/preparing_structures.html
-
June 3, 2011 at 6:56 pm #5716Anonymous
According to the documentation (http://www.rosettacommons.org/manuals/archive/rosetta3.2.1_user_guide/app_relax_command.html), the default for relax is score12 (that should be the default for most applications dealing with just proteins). If you’re concerned, for most applications you can explicitly specify score12 weights with a “-score:weights score12_full” command line option.
-
-
AuthorPosts
- You must be logged in to reply to this topic.