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Kopec, J.

Publications and source records attributed to Kopec, J..

2 recordsLinked to original sources

PIRATE: Plundering AlphaFold Predictions to Automate Protein Engineering

An important characteristic for many proteins is the presence of flexible loops or linkers known as intrinsically disordered regions. One downside to many of the state-of-the-art disorder prediction approaches is that they require significant computational time for each inference. Here, we introduce three novel surrogate models trained on AlphaFold2 predictions that rapidly encode local, regional, and global structural properties directly from primary sequence. We combined the outputs from these surrogate models, in an approach we term PIRATE, and show that this approach approximates the performance of AlphaFold2 for disorder prediction. Additionally, we show that PIRATE is much more sensitive to the effects of point mutants on disorder at distal sites than many current disorder prediction methods. Furthermore, we show that in the context of a greedy exploration algorithm, PIRATEs ability to evaluate differences between point mutants makes it ideal for automating disorder-related protein engineering tasks.

biochemistry↗

Structural basis of human 5,10-methylenetetrahydrofolate reductase (MTHFR) regulation by phosphorylation and S-adenosylmethionine inhibition

The folate and methionine cycles are crucial to the biosynthesis of lipids, nucleotides and proteins, and production of the global methyl donor S-adenosylmethionine (SAM). 5,10-methylenetetrahydrofolate reductase (MTHFR) represents a key regulatory connection between these cycles, generating 5-methyltetrahydrofolate for initiation of the methionine cycle, and undergoing allosteric inhibition by its end product SAM. Our 2.5 [A] resolution crystal structure of human MTHFR reveals a unique architecture, appending the well-conserved catalytic TIM-barrel to a eukaryote-only SAM-binding domain. The latter domain of novel fold provides the predominant interface for MTHFR homo-dimerization, positioning the N-terminal serine-rich phosphorylation region into proximity with the C-terminal SAM-binding domain. This explains how MTHFR phosphorylation, identified on 11 N-terminal residues (16-total), increases sensitivity to SAM binding and inhibition. Finally, we demonstrate the 25-amino-acid inter-domain linker enables conformational plasticity and propose it to be a key mediator of SAM regulation.

biochemistry↗