[cctbxbb] Re: reduce2 and cell construction from python script

import sys from iotbx import pdb as pdb from mmtbx import model as mdl from mmtbx.command_line import reduce2 # Load the mmcif file model_filename = sys.argv[1] # Get the model file name from the command line protein = pdb.input(file_name=model_filename) # Load the model model = mdl.manager(model_input=protein) # Create the model manager #trim hidrogen atoms and solvent model_no_H = model.remove_hydrogens() # Remove hydrogen atoms model_no_H_no_solvent = model_no_H.remove_solvent() # Remove solvent # add hydrogens using reduce in nuclear position model_clean = reduce2(model = model_no_H_no_solvent, mode = 'nuclear') # Add hydrogens hierarchy = model_clean.get_hierarchy().expand_to_p1() # Get the hierarchy Il giorno gio 13 feb 2025 alle ore 23:08 Pavel Afonine ha scritto:

Hi Enrico,

this works for me:

phenix.fetch_pdb 2gim

phenix.model_statistics 2gim.cif

mmtbx.reduce2 2gim.cif

Something must be lost in communication. Can you provide complete set of steps that lead to the crash?

Pavel On 2/13/25 13:55, Enrico Ravera wrote:

Dear Pavel, many thanks. It ran until the reduce2 part, where it gives the following error: File "/home/ravera/miniconda3/envs/cctbx/lib/python3.13/site-packages/mmtbx/monomer_library/pdb_interpretation.py", line 1572, in resolve_unexpected mod_mod_id = mod_dict["NH1NOTPRO"] the file i am parsing is https://files.rcsb.org/view/2GIM.cif

Any clues?

Cheers,

E.

Il giorno gio 13 feb 2025 alle ore 20:42 Pavel Afonine ha scritto:

...

Enrico,

here are the steps (check for typos as I was typing all the below from memory):

...

1) read in a mmcif file (which I think I can do following the tutorial);

pdb_inp = iotbx.pdb.input(file_name = "4znn.pdb") # can be PDB or mmCIF model = mmtbx.model.manager(model_input = pdb_inp)

...

2) trim the solvent and hydrogen atoms (probably I can do it following the tutorial);

model_no_H = model.remove_hydrogens()

model_no_water = model.remove_solvent()

though better:

selection = model.selection("not (element H or element D or water)")

model_trimmed = model.select(selection)

...

3) run reduce2 to get hydrogens in the nuclear positions (no clue);

Run mmtbx.reduce OR mmtbx.reduce2 OR mmtbx.hydrogenate

to add H. I have no idea about the difference between the three commands (perhaps just the mess that someone has to finally get brave enough to clean!), but all three are supposed to add H.

Also, you should be able to access the above calls programmatically, at Python script level, not running in the CL.

...

4) get the full content of the unit cell (no clue).

Do you mean expand to P1 (if original symmetry is not P1)? If so, then

hierarchy = model.get_hierarchy().expand_to_p1()

Happy to answer questions! Pavel