Book Image

Bioinformatics with Python Cookbook

By : Tiago R Antao, Tiago Antao
Book Image

Bioinformatics with Python Cookbook

By: Tiago R Antao, Tiago Antao

Overview of this book

Table of Contents (16 chapters)
Bioinformatics with Python Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Computing molecular distances on a PDB file


Here, we will find atoms closer to three zincs on the 1TUP model. We will consider several distances to these zincs. We will take this opportunity to discuss the performance of algorithms.

Getting ready

You can find this content in the 06_Prot/Distance.ipynb notebook. Take a look at the Bio.PDB recipe.

How to do it...

Take a look at the following steps:

  1. Let's load our model as follows:

    from __future__ import print_function
    from Bio import PDB
    repository = PDB.PDBList()
    parser = PDB.PDBParser()
    repository.retrieve_pdb_file('1TUP', pdir='.')
    p53_1tup = parser.get_structure('P 53', 'pdb1tup.ent')
  2. We will now get our zincs against which we perform later comparisons:

    zns = []
    for atom in p53_1tup.get_atoms():
        if atom.element == 'ZN':
            zns.append(atom)
    for zn in zns:
            print(zn, zn.coord)
    • You should see three zinc atoms.

  3. Then, let's define a function to get the distance between one atom and a set of other atoms as follows:

    import math
    def get_closest_atoms...