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Hello,
I am trying to fit a crystal pdb into a cryo-EM density map using DireX. According to the tutorials on the web, I should do refinement and minimization. However, when I tried to do minimization after refinement, DireX informed me of this information "Did not converge! No structure generated!". I want to know the reason.
Thank you!

Hi,

did you read in the original model with the -pdb option for the minimization run?

If you want to run several consecutive runs, the scheme looks like this:
direx -pdb start.pdb -cur model1.pdb ...
direx -pdb start.pdb -p model1.pdb -cur model2.pdb ...
direx -pdb start.pdb -p model2.pdb -cur model3.pdb ...

Since DireX learns the topology, bond lengths, angles, etc from the structure read with -pdb , there could be problems when you directly read in the direx output, as small errors in the output accumulate.

Hope this helped.
Gunnar