Monthly Archives: December 2020

OPIGmas 2020, Pandemic Edition

Not even a global pandemic can halt our annual celebrations. Festivus, move over. OPIGmas is here.

We were all lucky enough to have electricity; computers with webcams and microphones (Dan’s dalek incantations notwithstanding); and network connections; and somehow (for some of us) the time, to gather together around our twenty-first century electronic hearths and celebrate: Zoom, Gather Town, Among Us, Skribbl.io, and Codenames.

The much-awaited Secret Santa often reveals how naughty or nice the sender is, and sometimes surprising details about the relationship of the sender and recipient (I’m looking in the general direction of Dominik and Brennan). The rules are simple: spend up to £10 GBP, and don’t buy anything the boss wouldn’t buy for someone… But despite the hypothesis that the longer someone had been in OPIG, the more ‘pointed’ the gift would be, exceptions could still be found.

Armed with her new Easy Learning “Times Tables Bumper Book”, the boss was anointed “CEO of ******* Everything”, with her new desk name plate. Without coordinating, the boss’ PA independently received a desk name plate as “Fixer of Everything”. Perfect, on both counts.

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An in vivo force sensor reveals varied mechanisms of co-translational force generation

This blog post comments on the results published by Fujiwara and co-workers in the 2020 Cell Reports article “Proteome-wide capture of co-translational protein dynamics in Bacillus subtilis using TnDR, a transposable protein-dynamics reporter.”

The study of mechanical force generation and its influence on biological systems has expanded in recent years. In the realm of nascent protein folding, we now know that both unstructured and folded nascent proteins generate forces on the order of piconewtons that propagate down the nascent chain. These forces can distort the functional site of the ribosome and may influence the rate of translation (PMIDs: 30824598, 29577725). It has also been shown that translational arrest can be relieved by mechanical force (PMID: 25908824). Much study has focused on so-called arrest peptides, short peptide sequences that interact so strongly with the ribosome exit tunnel that they can completely stall translation (e.g., SecM, MifM).

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Prediction of Parkinson subtypes at COXIC 2020

Last week I attended the COXIC seminar (joint seminar Oxford – Imperial focused on networks and complex systems) organised by Florian Klimm from Imperial College London (and former OPIG member!). We had several interesting at the seminar. However, one of them caught my eye more than the rest. It was the talk of Dr Sanjukta Krishnagopal (UCL) titled Predicting Parkinson’s Sub-types through Trajectory Clustering in Bipartite Networks, of which I will give a quick insight. Hope you like it (at least) as much as I did!

This blogpost is based on these two articles:

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Curious About the Origins of Computerized Molecules? Free Webinar Dec 22…

After the stunning announcement at CASP14 that DeepMind’s AlphaFold 2 had successfully predicted the structures of proteins from their sequence alone, it’s hard to believe we began this journey by representing molecules with punched cards…

Image of a punched card, showing 80 columns and 12 rows, with particular rectangular holes representing the 1 bits of binary numbers. The upper right corner is cut at an angle, to facilitate feeding the card into a punched card reader. The column numbers are printed along the bottom. The words “IBM UNITED KINGDOM LIMITED” are printed along the very bottom. This card is line 12 from a Fortran program, “12 PIFRA=(A(JB,37)-A(JB,99))/A(JB,47) PUX 0430”. Image Credit: Pete Birkinshaw, Manchester, U.K. CC BY 2.0

Tales of carrying stacks of punched cards to the computer centre with a line drawn diagonally on the side of the stack, to help put them back in order should you trip and fall—seem like another universe—but this is what passed for the human-computer interface in much of the mid-20th century.

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UMAP Visualization of SARS-CoV-2 Data in ChEMBL

CASP14: what Google DeepMind’s AlphaFold 2 really achieved, and what it means for protein folding, biology and bioinformatics

Disclaimer: this post is an opinion piece based on the experience and opinions derived from attending the CASP14 conference as a doctoral student researching protein modelling. When provided, quotes have been extracted from my notes of the event, and while I hope to have captured them as accurately as possible, I cannot guarantee that they are a word-by-word facsimile of what the individuals said. Neither the Oxford Protein Informatics Group nor I accept any responsibility for the content of this post.

You might have heard it from the scientific or regular press, perhaps even from DeepMind’s own blog. Google ‘s AlphaFold 2 indisputably won the 14^th Critical Assessment of Structural Prediction competition, a biannual blind test where computational biologists try to predict the structure of several proteins whose structure has been determined experimentally — yet not publicly released. Their results are so incredibly accurate that many have hailed this code as the solution to the long-standing protein structure prediction problem.

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Drawing Wavy Lines That Match Your Data, or, An Introduction to Kernel Density Estimation

One of the fundamental questions of statistics is “How likely is it that event X will occur, given what we’ve observed already?”. It’s a question that pops up in all sorts of different fields, and in our daily lives as well, so it’s well worth being able to answer rationally. Under the statistician’s favourite assumption that the observed data are independent and identically distributed (i.i.d.), we can use the data to construct a probability distribution; that is, if we’re about to observe a new data point, x*, we can say how likely it is that x* will take a specific value.

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