99281-88-6Relevant articles and documents
Fragment-Based Covalent Ligand Screening Enables Rapid Discovery of Inhibitors for the RBR E3 Ubiquitin Ligase HOIP
Johansson, Henrik,Tsai, Yi-Chun Isabella,Fantom, Ken,Chung, Chun-Wa,Kümper, Sandra,Martino, Luigi,Thomas, Daniel A.,Eberl, H. Christian,Muelbaier, Marcel,House, David,Rittinger, Katrin
supporting information, p. 2703 - 2712 (2019/02/14)
Modification of proteins with polyubiquitin chains is a key regulatory mechanism to control cellular behavior and alterations in the ubiquitin system are linked to many diseases. Linear (M1-linked) polyubiquitin chains play pivotal roles in several cellular signaling pathways mediating immune and inflammatory responses and apoptotic cell death. These chains are formed by the linear ubiquitin chain assembly complex (LUBAC), a multiprotein E3 ligase that consists of 3 subunits, HOIP, HOIL-1L, and SHARPIN. Herein, we describe the discovery of inhibitors targeting the active site cysteine of the catalytic subunit HOIP using fragmentbased covalent ligand screening. We report the synthesis of a diverse library of electrophilic fragments and demonstrate an integrated use of protein LC-MS, biochemical ubiquitination assays, chemical synthesis, and protein crystallography to enable the first structure-based development of covalent inhibitors for an RBR E3 ligase. Furthermore, using cell-based assays and chemoproteomics, we demonstrate that these compounds effectively penetrate mammalian cells to label and inhibit HOIP and NF-κB activation, making them suitable hits for the development of selective probes to study LUBAC biology. Our results illustrate the power of fragment-based covalent ligand screening to discover lead compounds for challenging targets, which holds promise to be a general approach for the development of cell-permeable inhibitors of thioester-forming E3 ubiquitin ligases.
HETEROARYL INHIBITORS OF PAD4
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Paragraph 00417-00418, (2018/03/28)
The present invention provides compounds useful as inhibitors of PAD4, compositions thereof, and methods of treating PAD4-related disorders.
A Small Molecule That Switches a Ubiquitin Ligase from a Processive to a Distributive Enzymatic Mechanism
Kathman, Stefan G.,Span, Ingrid,Smith, Aaron T.,Xu, Ziyang,Zhan, Jennifer,Rosenzweig, Amy C.,Statsyuk, Alexander V.
supporting information, p. 12442 - 12445 (2015/10/19)
E3 ligases are genetically implicated in many human diseases, yet E3 enzyme mechanisms are not fully understood, and there is a strong need for pharmacological probes of E3s. We report the discovery that the HECT E3 Nedd4-1 is a processive enzyme and that disruption of its processivity by biochemical mutations or small molecules switches Nedd4-1 from a processive to a distributive mechanism of polyubiquitin chain synthesis. Furthermore, we discovered and structurally characterized the first covalent inhibitor of Nedd4-1, which switches Nedd4-1 from a processive to a distributive mechanism. To visualize the binding mode of the Nedd4-1 inhibitor, we used X-ray crystallography and solved the first structure of a Nedd4-1 family ligase bound to an inhibitor. Importantly, our study shows that processive Nedd4-1, but not the distributive Nedd4-1:inhibitor complex, is able to synthesize polyubiquitin chains on the substrate in the presence of the deubiquitinating enzyme USP8. Therefore, inhibition of E3 ligase processivity is a viable strategy to design E3 inhibitors. Our study provides fundamental insights into the HECT E3 mechanism and uncovers a novel class of HECT E3 inhibitors.
Structure-Activity Relationships for Inhibition of Papain by Peptide Michael Acceptors
Liu, Siming,Hanzlik, Robert P.
, p. 1067 - 1075 (2007/10/02)
Two series of peptidyl Michael acceptors, N-Ac-L-Phe-NHCH2CH=CH-E with different electron withdrawing groups (E = CO2CH3, 1a; SO2CH3, 1b; CO2H, 1c; CN, 1d; CONH2, 1e; and C6H4-p-NO2, 1f) and R-NHCH2CH=CHCOOCH3 with different recognition and binding groups (R = N-Ac-D-Phe, 2a; N-Ac-L-Leu, 3a; N-Ac-L-Met, 4a; PhCH2CH2CO, 5a; PhCO, 6a), were synthesized and evaluated as inactivators against papain.It was found that the inhibition of papain by peptidyl Michael acceptors is a general phenomenon and that the intrinsic chemical reactivity of the E group in the Michael acceptors has a direct effect on the kinetics of the inactivation process as reflected in k2/Ki.At pH 6.2, the reactivity of papain toward the Michael acceptors is about 283 000-fold higher than the reactivity of the model thiol 3-mercaptopropionate.This large increase in reactivity is attributable to at least 2 factors; one is the low apparent pKa of Cys-25 of papain, and the other is the recruitment of catalytic power by specific enzyme-substrate interactions.The unexpectedly high reactivity of 1c (E = COOH) was rationalized by proposing a direct interaction of the acid group with His-159 in the active site of papain.The unexpected inactivity of 1f (E = C6H4-p-NO2) as a Michael acceptor and its very powerful competitive inhibition of papain were rationalized by molecular graphics which showed the nitrophenyl moiety rotated out of conjugation with the olefin and interacting instead with the hydrophobic S1' region of papain.A plot of log (k2/Ki) for 1a-6a vs log (kcat/Km) for analogous R-Gly-p-NA substrates was linear (r = 0.98) with slope 0.83, suggesting that the binding energy from specific enzyme-ligand interactions can be used to drive the self-inactivation reaction to almost the same extent as it is used to drive catalysis.
Carboxyl-Modified Amino Acids and Peptides as Protease Inhibitors
Thompson, Stewart A.,Andrews, Peter R.,Hanzlik, Robert P.
, p. 104 - 111 (2007/10/02)
Several types of carbonyl-modified amino acids and peptides were prepared in forms having N-terminal modifications (carrier fragments) suitable for one of several representative protease enzymes, and their inhibitory action toward those enzymes were evalu
