Molecular Features of CA-074 pH-Dependent Inhibition of Cathepsin B
| Autor: | Michael C. Yoon, Mitchell P. Christy, Von V. Phan, William H. Gerwick, Gregory Hook, Anthony J. O’Donoghue, Vivian Hook |
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| Rok vydání: | 2022 |
| Předmět: |
Biochemistry & Molecular Biology
Cathepsin L Dipeptides Cysteine Proteinase Inhibitors Hydrogen-Ion Concentration Medical Biochemistry and Metabolomics Biochemistry Cathepsins Article Mass Spectrometry Cathepsin B Molecular Docking Simulation Kinetics Medicinal and Biomolecular Chemistry Cytosol Animals Humans Cysteine Biochemistry and Cell Biology Lysosomes Peptides |
| Zdroj: | Biochemistry, vol 61, iss 4 Biochemistry |
| Popis: | CA-074 is a selective inhibitor of cathepsin B, a lysosomal cysteine protease. CA-074 has been utilized in numerous studies to demonstrate the role of this protease in cellular and physiological functions. Cathepsin B in numerous human disease mechanisms involves its translocation from acidic lysosomes of pH 4.6 to neutral pH 7.2 of cellular locations, including the cytosol and extracellular environment. To gain in-depth knowledge of CA-074 inhibition under these different pH conditions, this study evaluated the molecular features, potency, and selectivity of CA-074 for cathepsin B inhibition under acidic and neutral pH conditions. This study demonstrated that CA-074 is most effective at inhibiting cathepsin B at an acidic pH of 4.6 with nM potency, which was more than 100-fold more potent than its inhibition at a neutral pH of 7.2. The pH-dependent inhibition of CA-074 was abolished by methylation of its C-terminal proline, indicating the requirement for the free C-terminal carboxyl group for pH-dependent inhibition. Under these acidic and neutral pH conditions, CA-074 maintained its specificity for cathepsin B over other cysteine cathepsins, displayed irreversible inhibition, and inhibited diverse cleavages of peptide substrates of cathepsin B assessed by profiling mass spectrometry. Molecular docking suggested that pH-dependent ionic interactions of the C-terminal carboxylate of CA-074 occur with His110 and His111 residues in the S2' subsite of the enzyme at pH 4.6, but these interactions differ at pH 7.2. While high levels of CA-074 or CA-074Me (converted by cellular esterases to CA-074) are used in biological studies to inhibit cathepsin B at both acidic and neutral pH locations, it is possible that adjusted levels of CA-074 or CA-074Me may be explored to differentially affect cathepsin B activity at these different pH values. Overall, the results of this study demonstrate the molecular, kinetic, and protease specificity features of CA-074 pH-dependent inhibition of cathepsin B. |
| Databáze: | OpenAIRE |
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