Dear Xiang-Jun Lu,
the part of the mmCIF file comes from a loop "_atom_site.group_PDB". According
to the mmCIF dictionary,
" The group of atoms to which the atom site belongs. This data item is provided
for compatibility with the original Protein Data Bank format, and only for that
purpose."
I r
Recently, I came across and was a bit surprised by the different assignment
of HETATM vs. ATOM records for modified nucleotides in PDB vs. PDBx/mmCIF
format. Using PDB entry 1ehz (the crystal structure of yeast phenylalanine
tRNA at 1.93 Å resolution) as an example, 1MA58 in .pdb has atomic
coordin
