Bio.PDB parsing PDB file

Question

[Gunilla]

Hi, I am rather new to this, but I looking to learn Biopython. I am using Anaconda 5.3, Biopython 1.72, Jupyter 5.7.2 on Windows 10.
I am trying the following code:

from Bio.PDB import *
from Bio.PDB.PDBParser import PDBParser
parser = PDBParser()
struc = parser.get_structure('test', '1FAT.pdb')

However, I get a FileNotFoundError:

---

FileNotFoundError                         Traceback (most recent call last)
<ipython-input-5-bc8e45627a00> in <module>()
      4 from Bio.PDB.PDBParser import PDBParser
      5 p = PDBParser()
----> 6 struc = p.get_structure('test', '1FAT.pdb')

~\Anaconda3\lib\site-packages\Bio\PDB\PDBParser.py in get_structure(self, id, file)
     83             self.structure_builder.init_structure(id)
     84 
---> 85             with as_handle(file, mode='rU') as handle:
     86                 self._parse(handle.readlines())
     87 

~\Anaconda3\lib\contextlib.py in __enter__(self)
    110         del self.args, self.kwds, self.func
    111         try:
--> 112             return next(self.gen)
    113         except StopIteration:
    114             raise RuntimeError("generator didn't yield") from None

~\Anaconda3\lib\site-packages\Bio\File.py in as_handle(handleish, mode, **kwargs)
     99                 yield fp
    100         else:
--> 101             with open(handleish, mode, **kwargs) as fp:
    102                 yield fp
    103     else:

FileNotFoundError: [Errno 2] No such file or directory: '1FAT.pdb'

It can be that I am very tired at the moment, but I can't get it to work. I thought Bio.PDB was automatically set up to get files from the PDB database. I have tried to retrive the file from PDB first, and putting in the whole filepath, but I keep on getting the same error. I tried to understand what the error message tells me, but I must confess I don't completely understand it, more than it can't find the file. I will be very grateful for any help.

[Ram]

I thought Bio.PDB was automatically set up to get files from the PDB database

I don't think that's the case, you'll need to download the file first. Maybe Bio.PDB has a different method to download directly from PDB site, but it's not the parser.get_structure() method.

I have tried to retrive the file from PDB first, and putting in the whole filepath, but I keep on getting the same error.

Could you maybe show us the command that has the whole file path? Have you tried using that file path with vanilla file reading code? That will tell you if the parser's method is the problem or if the path itself is not being read properly. If you have spaces or special characters in the file path, many programs can error out.

EDIT:

From the manual:

How do I download structures from the PDB?

This can be done using the PDBList object, using the retrieve_pdb_file method. The argument for this method is the PDB identifier of the structure.

pdbl = PDBList()
pdbl.retrieve_pdb_file('1FAT')

[Gunilla]

Thank you! I got it to work when I used MMCIFParser() and downloaded the files in beforehand.