Monthly Archives: April 2023

Train Your Own Protein Language Model In Just a Few Lines of Code

Language models have token the world by storm recently and, given the already explored analogies between protein primary sequence and text, there’s been a lot of interest in applying these models to protein sequences. Interest is not only coming from academia and the pharmaceutical industry, but also some very unlikely suspects such as ByteDance – yes the same ByteDance of TikTok fame. So if you also fancy trying your hand at building a protein language model then read on, it’s surprisingly easy.

Training your own protein language model from scratch is made remarkably easy by the HuggingFace Transformers library, which allows you to specify a model architecture, tokenise your training data, and train a model in only a few lines of code. Under the hood, the Transformers library uses PyTorch (or optionally Tensorflow) models, allowing you to dig deeper into customising training or model architecture, or simply leave it to the highly abstracted Transformers library to handle it all for you.

For this article, I’ll assume you already understand how language models work, and are now looking to implement one yourself, trained from scratch.

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The State of Computational Protein Design

Last month, I had the privilege to attend the Keystone Symposium on Computational Design and Modeling of Biomolecules in beautiful Banff, Canada. This conference gave an incredible insight into the current state of the protein design field, as we are on the precipice of advances catalyzed by deep learning.

Here are my key takeaways from the conference:

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How ChatGPT changed my writing as an ESL speaker

It’s not always easy to live in an Anglophone scientific world when English isn’t your first language. When careers are built upon the ability to communicate ideas clearly and eloquently, struggling to find the right words can be a real hindrance to explain your science in a way that is taken seriously. Contrary to popular belief, it’s not something you can simply “work” on. Often, it doesn’t matter how many books you’ve read, how many years of education you have, or how articulate you are in your original language — your brain will refuse to summon the right expression, or get stuck in a construction that a native speaker would never use. Struggling with a second language is very much a biological phenomenon.

The standard recommendation for ESL (English as a Second Language) speakers has long been to ask a native colleague to read through any text that needs to be published or submitted somewhere (such as an article or a grant application). Well-intentioned as this advice may be, there are multiple problems with it. Lingua franca or not, only 15% of the world population speaks English, of which only 5% are native speakers — meaning that for most scientists not working in Anglophone countries, the option is rarely available. Even when available, it is unreasonable to expect these colleagues to add charitable proof-reading to their workload simply because they happened to be born speaking a different language. But, most importantly, I have always felt — and I want to emphasize that I truly believe most people who issue this kind of advice to be well-intentioned — that the underliying message sounds too much like “you need vetting by a member of our select linguistic club if you want your ideas to be taken seriously“.

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Be a computational chemist and you must be a jack of all trades

Being a jack of all trades brings to mind someone who has extensive multidisciplinary expertise and is equipped with many tools in their toolbox to solve different problems. A jack of all trades is a great succinct description for computational chemists in drug discovery.

Recently I had a great conversation with Dr. Arjun Narayanan, a Senior Research Scientist at Vertex Pharmaceuticals and a jack of all trades as a computational chemist. In this blog post, I’ll describe what he does as a computational chemist, the problems he solves, and the new tools he’s looking forward to adding to his toolbox.

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Better histograms with Python

Histograms are frequently used to visualize the distribution of a data set or to compare between multiple distributions. Python, via matplotlib.pyplot, contains convenient functions for plotting histograms; the default plots it generates, however, leave much to be desired in terms of visual appeal and clarity.

The two code blocks below generate histograms of two normally distributed sets using default matplotlib.pyplot.hist settings and then, in the second block, I add some lines to improve the data presentation. See the comments to determine what each individual line is doing.

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BRICS Decomposition in 3D

Inspired by this blog post by the lovely Kate, I’ve been doing some BRICS decomposing of molecules myself. Like the structure-based goblin that I am, though, I’ve been applying it to 3D structures of molecules, rather than using the smiles approach she detailed. I thought it may be helpful to share the code snippets I’ve been using for this: unsurprisingly, it can also be done with RDKit!

I’ll use the same example as in the original blog post, propranolol.

1DY4: CBH1 IN COMPLEX WITH S-PROPRANOLOL

First, I import RDKit and load the ligand in question:

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AI-pril Fools

As my turn to write a blog post has fallen a few days after April 1st, I decided I would write an April Fools’ Day-inspired post and ask everyone’s favourite chatbot to tell me some jokes.

I asked ChatGPT to tell me a knock-knock joke, prompting it with various topics relevant to OPIG (including AI, antibodies, drug discovery and proteins) to see what it could come up with. I’d argue that we’re playing fast and loose with the definition of a joke (several of these just made me cringe), but here are some of the results…

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An Overview of Clustering Algorithms

During the first 6 months of my DPhil, I worked on clustering antibodies and I thought I would share what I learned about these algorithms. Clustering is an unsupervised data analysis technique that groups a data set into subsets of similar data points. The main uses of clustering are in exploratory data analysis to find hidden patterns or data compression, e.g. when data points in a cluster can be treated as a group. Clustering algorithms have many applications in computational biology, such as clustering antibodies by structural similarity. Actually, this is objectively the most important application and I don’t see why anyone would use it for anything else.

There are several types of clustering algorithms that offer different advantages.

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PLIP on PDBbind with Python

Today’s blog post is about using PLIP to extract information about interactions between a protein and ligand in a bound complex, using data from PDBbind. The blog post will cover how to combine the protein pdb file and the ligand mol2 file into a pdb file, and how to use PLIP in a high-throughput manner with python.

In order for PLIP to consider the ligand as one molecule interacting with the protein, we need to modify the mol2 file of the ligand. The 8th column of the atom portion of a mol2 file (the portion starts with @<TRIPOS>ATOM) includes the ID of the ligand that the atom belongs to. Most often all the atoms have the same ligand ID, but for peptides for instance, the atoms have the ID of the residue they’re part of. The following code snippet will make the required changes:

ligand_file = 'data/5oxm/5oxm_ligand.mol2'

with open(ligand_file, 'r') as f:
    ligand_lines = f.readlines()

mod = False
for i in range(len(ligand_lines)):
    line = ligand_lines[i]
    if line == '@&lt;TRIPOS&gt;BOND\n':
        mod = False
        
    if mod:
        ligand_lines[i] = line[:59] + 'ISK     ' + line[67:]
        
    if line == '@&lt;TRIPOS&gt;ATOM\n':
        mod = True

with open('data/5oxm/5oxm_ligand_mod.mol2', 'w') as g:
    for j in ligand_lines:
        g.write(j)
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