Post-proline cleaving enzymes also show specificity to reduced cysteine.

Kalaninova, Z.; Portasikova, J. M.; Jireckova, B.; Polak, M.; Novakova, J.; Kavan, D.; Novak, P.; Man, P.

doi:10.1101/2024.07.12.603020

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bioRxiv · 10.1101/2024.07.12.603020

Post-proline cleaving enzymes also show specificity to reduced cysteine.

Kalaninova, Z.·Portasikova, J. M.·Jireckova, B.·Polak, M.·Novakova, J.·Kavan, D.·Novak, P.·Man, P.

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Abstract

In proteomics, post-proline cleaving enzymes (PPCEs) like Aspergillus niger prolyl endopeptidase and neprosin complement proteolytic tools because proline is a stop site for many proteases. However, our systematic analysis of cleavage preferences showed that both PPCEs also display specificity to reduced cysteine. Post-cysteine cleavage was blocked by Cys alkylation, explaining why this activity has remained undetected. Our findings redefine their applicability and how we study and interpret their cleavage mechanism.

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Kalaninova, Z., Portasikova, J. M., Jireckova, B., Polak, M., Novakova, J., Kavan, D., Novak, P., Man, P.. 2024-07-12. Post-proline cleaving enzymes also show specificity to reduced cysteine.. https://doi.org/10.1101/2024.07.12.603020

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