Good day I am a researcher studying antibiotic interaction and trying to make a model with a substrate covalently bound to the active site. There is a homolog with a crystal structure (PDB: 4KQO), and I am going to add the bound substrate in this pdb file to my target protein where the mode was generated by alphafold server. Although the workflow shall be simple, I still have some problems, could you kindly help? 1. Firstly, I would like to check whether the model of 4KQO is good enough for modeling, by examining the electron density map (open 4KQO, open 4KQO from eds). However, I found that it is a bit different from the tutorial (https://www.cgl.ucsf.edu/chimerax/docs/quickstart/index.html, pdb:1a0m) that the electron density of 4KQO did not cover the substrate molecule. I am totally ignorant in crystallography, so, how could I visualize the electron density of the substrate? by any symmetry operation / command so that I could check whether there is "electron density in the substrate" ? 2. I aligned 4KQO with the alphafold generated model, and I deleted the protein from 4KQO, and combined the two model, make a bond between the active residue with the substrate, however, I am not sure how to (1) check the bond length and angle is appropriately assigned, and (2) do energy minimization to reorientate side change to eliminate the crash with the substrate. Thank you very much for your help in advance Have a nice weekend