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Mechanism of Inhibition of Cathepsin K by Potent, Selective 1,5-Diacylcarbohydrazides: A New Class of Mechanism-Based Inhibitors of Thiol Proteases
The nature of the inhibition of thiol proteases by a new class of mechanism-based inhibitors, 1,5-diacylcarbohydrazides, is described. These potent, time-dependent, active-site spanning inhibitors include compounds that are selective for cathepsin K, a cysteine protease unique to osteoclasts. The 1,...
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Published in: | Biochemistry (Easton) 1999-11, Vol.38 (48), p.15893-15902 |
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creator | Bossard, Mary J Tomaszek, Thaddeus A Levy, Mark A Ijames, Carl F Huddleston, Michael J Briand, Jacques Thompson, Scott Halpert, Stacie Veber, Daniel F Carr, Steven A Meek, Thomas D Tew, David G |
description | The nature of the inhibition of thiol proteases by a new class of mechanism-based inhibitors, 1,5-diacylcarbohydrazides, is described. These potent, time-dependent, active-site spanning inhibitors include compounds that are selective for cathepsin K, a cysteine protease unique to osteoclasts. The 1,5-diacylcarbohydrazides are slow substrates for members of the papain superfamily with inhibition resulting from slow enzyme decarbamylation. Enzyme-catalyzed hydrolysis of 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide is accompanied by formation of a hydrazide-containing product and a carbamyl−enzyme intermediate that is sufficiently stable to be observed by mass spectrometry and NMR. Stopped-flow studies yield a saturation limited value of 43 s-1 for the rate of cathepsin K acylation by 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide. Inhibition potency varies among proteases tested as reflected by 2−3 orders of magnitude differences in K i and k obs/I, but all eventually form the same stable covalent intermediate. Reactivation rates are equivalent for all enzymes tested (1 × 10-4 s-1), indicating hydrolysis of a common carbamyl−enzyme form. NMR spectroscopic studies with cathepsin K and 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide provide evidence of inhibitor cleavage to generate a covalent carbamyl−enzyme intermediate rather than a tetrahedral complex. The product Cbz-Leu-hydrazide does not appear enzyme-bound after cleavage in the NMR spectra, suggesting that the stable inhibited form of the enzyme is the thioester complex. 1,5-Diacylcarbohydrazides represent a new class of unreactive cysteine protease inhibitors that share a common mechanism of action across members of the papain superfamily. Both S and S‘ subsite interactions are exploited in achieving high selectivity and potency. |
doi_str_mv | 10.1021/bi991193+ |
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These potent, time-dependent, active-site spanning inhibitors include compounds that are selective for cathepsin K, a cysteine protease unique to osteoclasts. The 1,5-diacylcarbohydrazides are slow substrates for members of the papain superfamily with inhibition resulting from slow enzyme decarbamylation. Enzyme-catalyzed hydrolysis of 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide is accompanied by formation of a hydrazide-containing product and a carbamyl−enzyme intermediate that is sufficiently stable to be observed by mass spectrometry and NMR. Stopped-flow studies yield a saturation limited value of 43 s-1 for the rate of cathepsin K acylation by 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide. Inhibition potency varies among proteases tested as reflected by 2−3 orders of magnitude differences in K i and k obs/I, but all eventually form the same stable covalent intermediate. Reactivation rates are equivalent for all enzymes tested (1 × 10-4 s-1), indicating hydrolysis of a common carbamyl−enzyme form. NMR spectroscopic studies with cathepsin K and 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide provide evidence of inhibitor cleavage to generate a covalent carbamyl−enzyme intermediate rather than a tetrahedral complex. The product Cbz-Leu-hydrazide does not appear enzyme-bound after cleavage in the NMR spectra, suggesting that the stable inhibited form of the enzyme is the thioester complex. 1,5-Diacylcarbohydrazides represent a new class of unreactive cysteine protease inhibitors that share a common mechanism of action across members of the papain superfamily. Both S and S‘ subsite interactions are exploited in achieving high selectivity and potency.</description><identifier>ISSN: 0006-2960</identifier><identifier>EISSN: 1520-4995</identifier><identifier>DOI: 10.1021/bi991193+</identifier><identifier>PMID: 10625455</identifier><language>eng</language><publisher>United States: American Chemical Society</publisher><subject>Binding Sites ; Cathepsin K ; Cathepsins - antagonists & inhibitors ; Chromatography, High Pressure Liquid ; Enzyme Reactivators ; Hydrazines - chemistry ; Hydrazines - pharmacology ; Kinetics ; Leucine - analogs & derivatives ; Leucine - chemistry ; Leucine - pharmacology ; Magnetic Resonance Spectroscopy ; Mass Spectrometry ; Papain - antagonists & inhibitors ; Protease Inhibitors - pharmacology ; Spectrophotometry</subject><ispartof>Biochemistry (Easton), 1999-11, Vol.38 (48), p.15893-15902</ispartof><rights>Copyright © 1999 American Chemical Society</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-a412t-746a8cd03968fed95ea53bbbfaffe0de3cdc8b0e5463ab8dc315d4fdc5673f573</citedby><cites>FETCH-LOGICAL-a412t-746a8cd03968fed95ea53bbbfaffe0de3cdc8b0e5463ab8dc315d4fdc5673f573</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>315,786,790,27957,27958</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/10625455$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Bossard, Mary J</creatorcontrib><creatorcontrib>Tomaszek, Thaddeus A</creatorcontrib><creatorcontrib>Levy, Mark A</creatorcontrib><creatorcontrib>Ijames, Carl F</creatorcontrib><creatorcontrib>Huddleston, Michael J</creatorcontrib><creatorcontrib>Briand, Jacques</creatorcontrib><creatorcontrib>Thompson, Scott</creatorcontrib><creatorcontrib>Halpert, Stacie</creatorcontrib><creatorcontrib>Veber, Daniel F</creatorcontrib><creatorcontrib>Carr, Steven A</creatorcontrib><creatorcontrib>Meek, Thomas D</creatorcontrib><creatorcontrib>Tew, David G</creatorcontrib><title>Mechanism of Inhibition of Cathepsin K by Potent, Selective 1,5-Diacylcarbohydrazides: A New Class of Mechanism-Based Inhibitors of Thiol Proteases</title><title>Biochemistry (Easton)</title><addtitle>Biochemistry</addtitle><description>The nature of the inhibition of thiol proteases by a new class of mechanism-based inhibitors, 1,5-diacylcarbohydrazides, is described. These potent, time-dependent, active-site spanning inhibitors include compounds that are selective for cathepsin K, a cysteine protease unique to osteoclasts. The 1,5-diacylcarbohydrazides are slow substrates for members of the papain superfamily with inhibition resulting from slow enzyme decarbamylation. Enzyme-catalyzed hydrolysis of 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide is accompanied by formation of a hydrazide-containing product and a carbamyl−enzyme intermediate that is sufficiently stable to be observed by mass spectrometry and NMR. Stopped-flow studies yield a saturation limited value of 43 s-1 for the rate of cathepsin K acylation by 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide. Inhibition potency varies among proteases tested as reflected by 2−3 orders of magnitude differences in K i and k obs/I, but all eventually form the same stable covalent intermediate. Reactivation rates are equivalent for all enzymes tested (1 × 10-4 s-1), indicating hydrolysis of a common carbamyl−enzyme form. NMR spectroscopic studies with cathepsin K and 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide provide evidence of inhibitor cleavage to generate a covalent carbamyl−enzyme intermediate rather than a tetrahedral complex. The product Cbz-Leu-hydrazide does not appear enzyme-bound after cleavage in the NMR spectra, suggesting that the stable inhibited form of the enzyme is the thioester complex. 1,5-Diacylcarbohydrazides represent a new class of unreactive cysteine protease inhibitors that share a common mechanism of action across members of the papain superfamily. Both S and S‘ subsite interactions are exploited in achieving high selectivity and potency.</description><subject>Binding Sites</subject><subject>Cathepsin K</subject><subject>Cathepsins - antagonists & inhibitors</subject><subject>Chromatography, High Pressure Liquid</subject><subject>Enzyme Reactivators</subject><subject>Hydrazines - chemistry</subject><subject>Hydrazines - pharmacology</subject><subject>Kinetics</subject><subject>Leucine - analogs & derivatives</subject><subject>Leucine - chemistry</subject><subject>Leucine - pharmacology</subject><subject>Magnetic Resonance Spectroscopy</subject><subject>Mass Spectrometry</subject><subject>Papain - antagonists & inhibitors</subject><subject>Protease Inhibitors - pharmacology</subject><subject>Spectrophotometry</subject><issn>0006-2960</issn><issn>1520-4995</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>1999</creationdate><recordtype>article</recordtype><recordid>eNplkc1u1DAUhS0EokNhwQsgLxBCogE7jp0xuzJAKS0wUgMLNpZ_rhWXTDzYGWBYseUFeECehAxpKyRWV1fn0zlX5yJ0l5LHlJT0iQlSUirZo2toRnlJikpKfh3NCCGiKKUge-hWzufjWpG6uon2KBElrzifoV9vwLa6D3mFo8fHfRtMGELsd9tCDy2sc-jxCTZbvIwD9MMBPoMO7BC-AKYHvHgetN12VicT261L-ntwkJ_-_vETH-K38BUvOp3zzu0qqHimM7jLrJj-qk0bYoeXacwY1Xwb3fC6y3DnYu6j9y9fNItXxem7o-PF4WmhK1oORV0JPbeOMCnmHpzkoDkzxnjtPRAHzDo7NwR4JZg2c2cZ5a7yznJRM89rto8eTL7rFD9vIA9qFbKFrtM9xE1WQjJJa1aO4MMJtCnmnMCrdQornbaKErV7grp8wojeu_DcmBW4f8Cp9BEoJiDkAb5d6Tp9UuNZNVfN8kx9eH3SfBSNUEcjf3_itc3qPG5SP1byf-4fStyfGQ</recordid><startdate>19991130</startdate><enddate>19991130</enddate><creator>Bossard, Mary J</creator><creator>Tomaszek, Thaddeus A</creator><creator>Levy, Mark A</creator><creator>Ijames, Carl F</creator><creator>Huddleston, Michael J</creator><creator>Briand, Jacques</creator><creator>Thompson, Scott</creator><creator>Halpert, Stacie</creator><creator>Veber, Daniel F</creator><creator>Carr, Steven A</creator><creator>Meek, Thomas D</creator><creator>Tew, David G</creator><general>American Chemical Society</general><scope>BSCLL</scope><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7X8</scope></search><sort><creationdate>19991130</creationdate><title>Mechanism of Inhibition of Cathepsin K by Potent, Selective 1,5-Diacylcarbohydrazides: A New Class of Mechanism-Based Inhibitors of Thiol Proteases</title><author>Bossard, Mary J ; Tomaszek, Thaddeus A ; Levy, Mark A ; Ijames, Carl F ; Huddleston, Michael J ; Briand, Jacques ; Thompson, Scott ; Halpert, Stacie ; Veber, Daniel F ; Carr, Steven A ; Meek, Thomas D ; Tew, David G</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-a412t-746a8cd03968fed95ea53bbbfaffe0de3cdc8b0e5463ab8dc315d4fdc5673f573</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>1999</creationdate><topic>Binding Sites</topic><topic>Cathepsin K</topic><topic>Cathepsins - antagonists & inhibitors</topic><topic>Chromatography, High Pressure Liquid</topic><topic>Enzyme Reactivators</topic><topic>Hydrazines - chemistry</topic><topic>Hydrazines - pharmacology</topic><topic>Kinetics</topic><topic>Leucine - analogs & derivatives</topic><topic>Leucine - chemistry</topic><topic>Leucine - pharmacology</topic><topic>Magnetic Resonance Spectroscopy</topic><topic>Mass Spectrometry</topic><topic>Papain - antagonists & inhibitors</topic><topic>Protease Inhibitors - pharmacology</topic><topic>Spectrophotometry</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Bossard, Mary J</creatorcontrib><creatorcontrib>Tomaszek, Thaddeus A</creatorcontrib><creatorcontrib>Levy, Mark A</creatorcontrib><creatorcontrib>Ijames, Carl F</creatorcontrib><creatorcontrib>Huddleston, Michael J</creatorcontrib><creatorcontrib>Briand, Jacques</creatorcontrib><creatorcontrib>Thompson, Scott</creatorcontrib><creatorcontrib>Halpert, Stacie</creatorcontrib><creatorcontrib>Veber, Daniel F</creatorcontrib><creatorcontrib>Carr, Steven A</creatorcontrib><creatorcontrib>Meek, Thomas D</creatorcontrib><creatorcontrib>Tew, David G</creatorcontrib><collection>Istex</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>MEDLINE - Academic</collection><jtitle>Biochemistry (Easton)</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Bossard, Mary J</au><au>Tomaszek, Thaddeus A</au><au>Levy, Mark A</au><au>Ijames, Carl F</au><au>Huddleston, Michael J</au><au>Briand, Jacques</au><au>Thompson, Scott</au><au>Halpert, Stacie</au><au>Veber, Daniel F</au><au>Carr, Steven A</au><au>Meek, Thomas D</au><au>Tew, David G</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Mechanism of Inhibition of Cathepsin K by Potent, Selective 1,5-Diacylcarbohydrazides: A New Class of Mechanism-Based Inhibitors of Thiol Proteases</atitle><jtitle>Biochemistry (Easton)</jtitle><addtitle>Biochemistry</addtitle><date>1999-11-30</date><risdate>1999</risdate><volume>38</volume><issue>48</issue><spage>15893</spage><epage>15902</epage><pages>15893-15902</pages><issn>0006-2960</issn><eissn>1520-4995</eissn><notes>istex:E20BBF723DA3126540992C4333C4D5BBB6DCEBD1</notes><notes>ark:/67375/TPS-VJKTZ6T6-G</notes><notes>ObjectType-Article-1</notes><notes>SourceType-Scholarly Journals-1</notes><notes>ObjectType-Feature-2</notes><notes>content type line 23</notes><abstract>The nature of the inhibition of thiol proteases by a new class of mechanism-based inhibitors, 1,5-diacylcarbohydrazides, is described. These potent, time-dependent, active-site spanning inhibitors include compounds that are selective for cathepsin K, a cysteine protease unique to osteoclasts. The 1,5-diacylcarbohydrazides are slow substrates for members of the papain superfamily with inhibition resulting from slow enzyme decarbamylation. Enzyme-catalyzed hydrolysis of 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide is accompanied by formation of a hydrazide-containing product and a carbamyl−enzyme intermediate that is sufficiently stable to be observed by mass spectrometry and NMR. Stopped-flow studies yield a saturation limited value of 43 s-1 for the rate of cathepsin K acylation by 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide. Inhibition potency varies among proteases tested as reflected by 2−3 orders of magnitude differences in K i and k obs/I, but all eventually form the same stable covalent intermediate. Reactivation rates are equivalent for all enzymes tested (1 × 10-4 s-1), indicating hydrolysis of a common carbamyl−enzyme form. NMR spectroscopic studies with cathepsin K and 2,2‘-N,N‘-bis(benzyloxycarbonyl)-l-leucinylcarbohydrazide provide evidence of inhibitor cleavage to generate a covalent carbamyl−enzyme intermediate rather than a tetrahedral complex. The product Cbz-Leu-hydrazide does not appear enzyme-bound after cleavage in the NMR spectra, suggesting that the stable inhibited form of the enzyme is the thioester complex. 1,5-Diacylcarbohydrazides represent a new class of unreactive cysteine protease inhibitors that share a common mechanism of action across members of the papain superfamily. Both S and S‘ subsite interactions are exploited in achieving high selectivity and potency.</abstract><cop>United States</cop><pub>American Chemical Society</pub><pmid>10625455</pmid><doi>10.1021/bi991193+</doi><tpages>10</tpages></addata></record> |
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subjects | Binding Sites Cathepsin K Cathepsins - antagonists & inhibitors Chromatography, High Pressure Liquid Enzyme Reactivators Hydrazines - chemistry Hydrazines - pharmacology Kinetics Leucine - analogs & derivatives Leucine - chemistry Leucine - pharmacology Magnetic Resonance Spectroscopy Mass Spectrometry Papain - antagonists & inhibitors Protease Inhibitors - pharmacology Spectrophotometry |
title | Mechanism of Inhibition of Cathepsin K by Potent, Selective 1,5-Diacylcarbohydrazides: A New Class of Mechanism-Based Inhibitors of Thiol Proteases |
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