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1.
Nature ; 629(8011): 435-442, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658751

RESUMO

WRN helicase is a promising target for treatment of cancers with microsatellite instability (MSI) due to its essential role in resolving deleterious non-canonical DNA structures that accumulate in cells with faulty mismatch repair mechanisms1-5. Currently there are no approved drugs directly targeting human DNA or RNA helicases, in part owing to the challenging nature of developing potent and selective compounds to this class of proteins. Here we describe the chemoproteomics-enabled discovery of a clinical-stage, covalent allosteric inhibitor of WRN, VVD-133214. This compound selectively engages a cysteine (C727) located in a region of the helicase domain subject to interdomain movement during DNA unwinding. VVD-133214 binds WRN protein cooperatively with nucleotide and stabilizes compact conformations lacking the dynamic flexibility necessary for proper helicase function, resulting in widespread double-stranded DNA breaks, nuclear swelling and cell death in MSI-high (MSI-H), but not in microsatellite-stable, cells. The compound was well tolerated in mice and led to robust tumour regression in multiple MSI-H colorectal cancer cell lines and patient-derived xenograft models. Our work shows an allosteric approach for inhibition of WRN function that circumvents competition from an endogenous ATP cofactor in cancer cells, and designates VVD-133214 as a promising drug candidate for patients with MSI-H cancers.


Assuntos
Regulação Alostérica , Descoberta de Drogas , Inibidores Enzimáticos , Proteômica , Helicase da Síndrome de Werner , Animais , Feminino , Humanos , Masculino , Camundongos , Regulação Alostérica/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Cisteína/efeitos dos fármacos , Cisteína/metabolismo , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Descoberta de Drogas/métodos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Instabilidade de Microssatélites , Modelos Moleculares , Helicase da Síndrome de Werner/antagonistas & inibidores , Helicase da Síndrome de Werner/química , Helicase da Síndrome de Werner/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Morte Celular/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo
3.
J Am Chem Soc ; 145(50): 27225-27229, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38051111

RESUMO

A total synthesis of the ingenane-derived diterpenoid (+)-euphorikanin A is described. Key to the strategy is a stereocontrolled one-pot sequence consisting of transannular aldol addition reaction, hemiketal formation, and subsequent semipinacol rearrangement that efficiently leads to the complete euphorikanin skeleton. Atroposelective ring-closing olefin metathesis proved critical for the stereospecific cascade, leading to formation of a (Z)-bicyclo[7.4.1]tetradecenone core. An additional salient feature of the route is pyrolysis of a bis-methylxanthate to cleanly furnish the natural product.

4.
J Am Chem Soc ; 143(22): 8261-8265, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34043906

RESUMO

We disclose the first total synthesis of (+)-euphorikanin A, an ingenane-derived natural product featuring an unprecedented 5/6/7/3-fused tetracyclic skeleton. Key to the approach is a SmI2-mediated ketyl-enoate reaction that leads to the formation of two rings in a single step. The polarity-reversed cyclization proceeds in excellent yield and high diastereoselectivity. Access to ring B is effected late in the synthesis by implementation of a number of chemoselective transformations, including in situ generation of a vinyl lithium species and subsequent intramolecular attack onto an α-ketolactone.


Assuntos
Produtos Biológicos/síntese química , Diterpenos/síntese química , Produtos Biológicos/química , Diterpenos/química , Conformação Molecular , Estereoisomerismo
5.
FEBS J ; 287(4): 708-720, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31420998

RESUMO

Streptomyces mobaraensis is a key player for the industrial production of the protein cross-linking enzyme microbial transglutaminase (MTG). Extra-cellular activation of MTG by the transglutaminase-activating metalloprotease (TAMP) is regulated by the TAMP inhibitory protein SSTI that belongs to the large Streptomyces subtilisin inhibitor (SSI) family. Despite decades of SSI research, the binding site for metalloproteases such as TAMP remained elusive in most of the SSI proteins. Moreover, SSTI is a MTG substrate, and the preferred glutamine residues for SSTI cross-linking are not determined. To address both issues, that is, determination of the TAMP and the MTG glutamine binding sites, SSTI was modified by distinct point mutations as well as elongation or truncation of the N-terminal peptide by six and three residues respectively. Structural integrity of the mutants was verified by the determination of protein melting points and supported by unimpaired subtilisin inhibitory activity. While exchange of single amino acids could not disrupt decisively the SSTI TAMP interaction, the N-terminally shortened variants clearly indicated the highly conserved Leu40-Tyr41 as binding motif for TAMP. Moreover, enzymatic biotinylation revealed that an adjacent glutamine pair, upstream from Leu40-Tyr41 in the SSTI precursor protein, is the preferred binding site of MTG. This extension peptide disturbs the interaction with TAMP. The structure of SSTI was furthermore determined by X-ray crystallography. While no structural data could be obtained for the N-terminal peptide due to flexibility, the core structure starting from Tyr41 could be determined and analysed, which superposes well with SSI-family proteins. ENZYMES: Chymotrypsin, EC3.4.21.1; griselysin (SGMPII, SgmA), EC3.4.24.27; snapalysin (ScNP), EC3.4.24.77; streptogrisin-A (SGPA), EC3.4.21.80; streptogrisin-B (SGPB), EC3.4.21.81; subtilisin BPN', EC3.4.21.62; transglutaminase, EC2.3.2.13; transglutaminase-activating metalloprotease (TAMP), EC3.4.-.-; tri-/tetrapeptidyl aminopeptidase, EC3.4.11.-; trypsin, EC3.4.21.4. DATABASES: The atomic coordinates and structure factors (PDB 6I0I) have been deposited in the Protein Data Bank (http://www.rcsb.org).


Assuntos
Proteínas de Bactérias/química , Glutamina/química , Streptomyces/enzimologia , Transglutaminases/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Biotinilação , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Glutamina/metabolismo , Cinética , Modelos Moleculares , Mutação Puntual , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Streptomyces/genética , Especificidade por Substrato , Transglutaminases/genética , Transglutaminases/metabolismo
6.
J Biotechnol ; 281: 115-122, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-29981445

RESUMO

Transglutaminase from Streptomyces mobaraensis (MTG) is an important enzyme for numerous industrial applications. Recombinant production requires proteolytic activation of the zymogen. The study provides a convenient procedure for the preparation of the transglutaminase-activating metalloprotease (TAMP) in Escherichia coli. In contrast to wtTAMP, rTAMP exhibited the P domain of convertases as molecular mass of 55.7 kDa suggested. Protein integrity was beneficially influenced by 2-5 mM CaCl2. Study of pH and temperature optima assigned rTAMP to the neutral metalloproteases, more heat-resistant than Dispase but not thermolysin. Zinc had no inhibiting effect but 3.1 µM EDTA completely reduced activity of 5 nM TAMP. MTG, exceeding concentration of rTAMP by three orders of magnitude, was largely activated within few minutes. The kinetic parameters KM (1.31 ±â€¯0.05 mM) and kcat (135 ±â€¯4.3 s-1), monitored by isothermal titration calorimetry (ITC), further highlighted catalytic efficiency (103,053 M-1 s-1) of rTAMP and rapid processing of MTG. ITC even revealed that inhibition of rTAMP by its intrinsic inhibitory protein SSTI was an enthalpy-driven process resulting in Kd of 199 ±â€¯37.9 nM. The production procedure of rTAMP in E. coli closes the gap between production and application of recombinant MTG and may enhance relevance of MTG-mediated reactions in pharmaceutical processes.


Assuntos
Proteínas de Bactérias , Escherichia coli/metabolismo , Metaloproteases , Streptomyces/enzimologia , Transglutaminases , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Escherichia coli/genética , Metaloproteases/genética , Metaloproteases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Transglutaminases/genética , Transglutaminases/metabolismo
7.
Org Lett ; 19(21): 6008-6011, 2017 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-29064717

RESUMO

The veterinary drug Alfaprostol and prostaglandin PGF2α have been synthesized in just nine steps. The strategy involved the conjugate addition of an alkyne to a bicyclic enal, available in three steps by a proline-catalyzed aldol reaction of succinaldehyde. In the case of Alfaprostol, this resulted in the shortest synthesis reported to date. For PGF2α, this approach improved our previous route by making the 1,4-addition and ozonolysis more operationally simple.

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