title: Design of ultrasensitive probes for human neutrophil elastase through hybrid combinatorial substrate library profiling.
abstract: The exploration of protease substrate specificity is generally restricted to naturally occurring amino acids, limiting the degree of conformational space that can be surveyed. We substantially enhanced this by incorporating 102 unnatural amino acids to explore the S1-S4 pockets of human neutrophil elastase. This approach provides hybrid natural and unnatural amino acid sequences, and thus we termed it the Hybrid Combinatorial Substrate Library. Library results were validated by the synthesis of individual tetrapeptide substrates, with the optimal substrate demonstrating more than three orders of magnitude higher catalytic efficiency than commonly used substrates of elastase. This optimal substrate was converted to an activity-based probe that demonstrated high selectivity and revealed the specific presence of active elastase during the process of neutrophil extracellular trap formation. We propose that this approach can be successfully used for any type of endopeptidase to deliver high activity and selectivity in substrates and probes.
authors.affiliation: Division of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Technology, Wroclaw 50-370, Poland.
authors.forename: Paulina
authors.initials: P
authors.lastname: Kasperkiewicz
authors.forename: Marcin
authors.initials: M
authors.lastname: Poreba
authors.forename: Scott J
authors.initials: SJ
authors.lastname: Snipas
authors.forename: Heather
authors.initials: H
authors.lastname: Parker
authors.forename: Christine C
authors.initials: CC
authors.lastname: Winterbourn
authors.forename: Guy S
authors.initials: GS
authors.lastname: Salvesen
authors.forename: Marcin
authors.initials: M
authors.lastname: Drag
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D001665:Binding Sites / Q000235:genetics; D020650:Combinatorial Chemistry Techniques; D015723:Gene Library; D006801:Humans; D007700:Kinetics; D019272:Leukocyte Elastase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015335:Molecular Probes / Q000235:genetics*; D015394:Molecular Structure; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D015335:Molecular Probes; D019272:Leukocyte Elastase