Discovery of Cell-Type-Specific and Disease-Related Enzymatic Activity Changes via Global Evaluation of Peptide Metabolism

Abstract

Cellular homeostasis is maintained by a complex network of reactions catalyzed by enormous numbers of enzymatic activities (the enzymome), which serve to determine the phenotypes of cells. Here, we focused on the enzymomics of proteases and peptidases because these enzymes are an important class of disease-related proteins. We describe a system that (A) simultaneously evaluates metabolic activities of peptides using a series of exogenous peptide substrates and (B) identifies the enzymes that metabolize the specified peptide substrate with high throughput. We confirmed that the developed system was able to discover cell-type-specific and disease-related exo- and endopeptidase activities and identify the responsible enzymes. For example, we found that the activity of the endopeptidase neurolysin is highly elevated in human colorectal tumor tissue samples. This simple but powerful enzymomics platform should be widely applicable to uncover cell-type-specific reactions and altered enzymatic functions with potential value as biomarkers or drug targets in various disease states and to investigate the mechanisms of the underlying pathologies.

ICBS 2017 in Shanghai—Illuminating Life with Chemical Innovation

“…117,118 In one example, global monitoring of peptide-metabolizing enzymatic activities led to the finding that the activity of the endopeptidase neurolysin is highly elevated in human colorectal tumor tissue samples. 119 The talk was concluded by highlighting that such “enzymomic” investigations will facilitate the characterization of disease-related proteins as potential drug targets or biomarkers.…”

“…Toru Komatsu (The University of Tokyo) presented a study using small molecular fluorescent substrate probes to report enzyme activities in biosamples . The methodology was deployed for characterizing disease-related enzymes in samples by globally monitoring their activities with a library of substrates, identifying those that specifically associated with disease. , In one example, global monitoring of peptide-metabolizing enzymatic activities led to the finding that the activity of the endopeptidase neurolysin is highly elevated in human colorectal tumor tissue samples . The talk was concluded by highlighting that such “enzymomic” investigations will facilitate the characterization of disease-related proteins as potential drug targets or biomarkers.…”

Potential of Enzymomics Methodologies to Characterize Disease-Related Protein Functions

“…61) The target protein was characterized as acylamino acid-releasing enzyme by means of the native electrophoresis-based protein-characterizing methodology termed the "diced electrophoresis gel assay." 59,60,62) The result indicates that, in response to lung inflammation, immune cells that exhibit acylamino acid-releasing enzyme (APEH) activity infiltrate into the lung, leading to increased APEH activity in inflammatory bronchoalveolar lavage fluid (BALF). Therefore, APEH activity in BALF could serve as a novel biomarker of immune cell infiltration.…”

“…Recently, one leading example that characterized altered peptide-metabolizing activities to discover novel disease-related enzymatic functions was reported. 63) Although the research is at an early stage, it should be possible in the future to extend substratebased comprehensive studies to cover a broad range of bio-chemical reactions.…”

Advancement of Peptide Nanobiotechnology via Emerging Microfluidic Technology

“…Peptides are ubiquitous in nature. They fulfill wide-ranging roles in including but not limited to, cell-cell recognition (epitopes) [1], metabolism (enzymes) [2], and cellular structure (actin) [3] in living systems. Being such a common motif in living systems, peptides are generally biocompatible and non-immunogenic and thus have been harnessed in biomaterials for various purposes [4,5,6].…”