# Production and application of peptidyl-lys metalloendopeptidase: advances, challenges, and future perspectives

## TL;DR

This review discusses peptidyl-lys metalloendopeptidases (PKMs), enzymes useful in proteomics for cleaving peptides, and their production and application advancements.

## Contribution

The paper highlights recent recombinant production advances that allow PKMs to function alongside trypsin and LysC.

## Key findings

- PKMs selectively cleave peptide bonds at lysine residues, aiding in proteomics.
- Recombinant technology enables tailored PKM modifications for specific analytical uses.
- PKMs have potential for broader application in novel proteomic methods.

## Abstract

Peptidyl-lys metalloendopeptidases (PKMs) are enzymes that selectively cleave peptide bonds at the N-terminus of lysine residues present in the P1′ position, making them valuable tools in proteomics. This mini-review presents an overview of PKMs, covering their traditional production from native sources, recent advances in recombinant production, and the current limitations in availability. The historical and current applications of PKMs in proteomics are discussed, highlighting their role in protein sequencing, peptide mapping, and mass spectrometry-based studies. Advances in recombinant technology now enable tailored modifications to PKM, allowing it to function not only as a sister enzyme to LysC but also to trypsin, thereby enhancing its suitability for specific analytical applications. The mini-review concludes with a forward-looking statement on PKM research, emphasizing the potential to broaden its use in novel proteomic methods and other applications.