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468 results on '"Yang, Jay"'

1. Olutasidenib (FT-2102) induces durable complete remissions in patients with relapsed or refractory IDH1-mutated AML.

Author

de Botton, Stéphane, Fenaux, Pierre, Yee, Karen, Récher, Christian, Wei, Andrew, Montesinos, Pau, Taussig, David, Pigneux, Arnaud, Braun, Thorsten, Curti, Antonio, Grove, Carolyn, Khwaja, Asim, Legrand, Ollivier, Peterlin, Pierre, Arnan, Montserrat, Blum, William, Cilloni, Daniela, Hiwase, Devendra, Jurcic, Joseph, Krauter, Jürgen, Thomas, Xavier, Watts, Justin, Yang, Jay, Polyanskaya, Olga, Brevard, Julie, Sweeney, Jennifer, Barrett, Emma, Cortes, Jorge, and Jonas, Brian

Subjects
Humans, Adult, Middle Aged, Aged, Aged, 80 and over, Pyridines, Quinolines, Leukemia, Myeloid, Acute, Prognosis, Isocitrate Dehydrogenase
Abstract

Olutasidenib (FT-2102) is a potent, selective, oral, small-molecule inhibitor of mutant isocitrate dehydrogenase 1 (mIDH1). Overall, 153 IDH1 inhibitor-naive patients with mIDH1R132 relapsed/refractory (R/R) acute myeloid leukemia (AML) received olutasidenib monotherapy 150 mg twice daily in the pivotal cohort of this study. The median age of participants was 71 years (range, 32-87 years) and the median number of prior regimens received by patients was 2 (1-7). The rate of complete remission (CR) plus CR with partial hematologic recovery (CRh) was 35%, and the overall response rate was 48%. Response rates were similar in patients who had, and who had not, received prior venetoclax. With 55% of patients censored at the time of data cut-off, the median duration of CR/CRh was 25.9 months. The median duration of overall response was 11.7 months, and the median overall survival was 11.6 months. Of 86 patients who were transfusion dependent at baseline, a 56-day transfusion independence was achieved in 29 (34%), which included patients in all response groups. Grade 3 or 4 treatment-emergent adverse events (≥10%) were febrile neutropenia and anemia (n = 31; 20% each), thrombocytopenia (n = 25; 16%), and neutropenia (n = 20; 13%). Differentiation syndrome adverse events of special interest occurred in 22 (14%) patients, with 14 (9%) grade ≥3 and 1 fatal case reported. Overall, olutasidenib induced durable remissions and transfusion independence with a well-characterized and manageable side effect profile. The observed efficacy represents a therapeutic advance in this molecularly defined, poor-prognostic population of patients with mIDH1 R/R AML. This trial was registered at www.clinicaltrials.gov as #NCT02719574.

Published
2023

2. Room-temperature structural studies of SARS-CoV-2 protein NendoU with an X-ray free-electron laser.

Author

Jernigan, Rebecca J, Logeswaran, Dhenugen, Doppler, Diandra, Nagaratnam, Nirupa, Sonker, Mukul, Yang, Jay-How, Ketawala, Gihan, Martin-Garcia, Jose M, Shelby, Megan L, Grant, Thomas D, Mariani, Valerio, Tolstikova, Alexandra, Sheikh, Michelle Z, Yung, Mimi Cho, Coleman, Matthew A, Zaare, Sahba, Kaschner, Emily K, Rabbani, Mohammad Towshif, Nazari, Reza, Zacks, Michele A, Hayes, Brandon, Sierra, Raymond G, Hunter, Mark S, Lisova, Stella, Batyuk, Alexander, Kupitz, Christopher, Boutet, Sebastien, Hansen, Debra T, Kirian, Richard A, Schmidt, Marius, Fromme, Raimund, Frank, Matthias, Ros, Alexandra, Chen, Julian J-L, Botha, Sabine, and Fromme, Petra

Subjects
Humans, Crystallography, X-Ray, Lasers, Temperature, Electrons, COVID-19, SARS-CoV-2, NSP15, NendoU, X-ray free-electron laser, serial femtosecond crystallography, Prevention, Infectious Diseases, Emerging Infectious Diseases, Vaccine Related, Biodefense, Infection, Chemical Sciences, Biological Sciences, Information and Computing Sciences, Biophysics
Abstract

NendoU from SARS-CoV-2 is responsible for the virus's ability to evade the innate immune system by cleaving the polyuridine leader sequence of antisense viral RNA. Here we report the room-temperature structure of NendoU, solved by serial femtosecond crystallography at an X-ray free-electron laser to 2.6 Å resolution. The room-temperature structure provides insight into the flexibility, dynamics, and other intrinsic properties of NendoU, with indications that the enzyme functions as an allosteric switch. Functional studies examining cleavage specificity in solution and in crystals support the uridine-purine cleavage preference, and we demonstrate that enzyme activity is fully maintained in crystal form. Optimizing the purification of NendoU and identifying suitable crystallization conditions set the benchmark for future time-resolved serial femtosecond crystallography studies. This could advance the design of antivirals with higher efficacy in treating coronaviral infections, since drugs that block allosteric conformational changes are less prone to drug resistance.

Published
2023

6. Enhancing anti-AML activity of venetoclax by isoflavone ME-344 through suppression of OXPHOS and/or purine biosynthesis in vitro

Author

Hurrish, Katie H., Su, Yongwei, Patel, Shraddha, Ramage, Cassandra L., Zhao, Jianlei, Temby, Brianna R., Carter, Jenna L., Edwards, Holly, Buck, Steven A., Wiley, Sandra E., Hüttemann, Maik, Polin, Lisa, Kushner, Juiwanna, Dzinic, Sijana H., White, Kathryn, Bao, Xun, Li, Jing, Yang, Jay, Boerner, Julie, Hou, Zhanjun, Al-Atrash, Gheath, Konoplev, Sergej N., Busquets, Jonathan, Tiziani, Stefano, Matherly, Larry H., Taub, Jeffrey W., Konopleva, Marina, Ge, Yubin, and Baran, Natalia

Published
2024
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7. Phase I First-in-Human Dose Escalation Study of the oral SF3B1 modulator H3B-8800 in myeloid neoplasms.

Author

Steensma, David, Wermke, Martin, Klimek, Virginia, Greenberg, Peter, Font, Patricia, Komrokji, Rami, Yang, Jay, Brunner, Andrew, Carraway, Hetty, Ades, Lionel, Al-Kali, Aref, Alonso-Dominguez, Juan, Alfonso-Piérola, Ana, Coombs, Catherine, Deeg, H, Flinn, Ian, Foran, James, Garcia-Manero, Guillermo, Maris, Michael, McMasters, Malgorzata, Micol, Jean-Baptiste, De Oteyza, Jaime, Thol, Felicitas, Wang, Eunice, Watts, Justin, Taylor, Justin, Stone, Richard, Gourineni, Vikram, Marino, Alyssa, Yao, Huilan, Destenaves, Benoit, Yuan, Xiaobin, Yu, Kun, Dar, Sara, Ohanjanian, Lernik, Kuida, Keisuke, Xiao, Jianjun, Scholz, Catherine, Gualberto, Antonio, and Platzbecker, Uwe

Subjects
Administration, Oral, Aged, Aged, 80 and over, Biomarkers, Tumor, Dose-Response Relationship, Drug, Female, Humans, Leukemia, Myeloid, Acute, Male, Middle Aged, Mutation, Missense, Myelodysplastic Syndromes, Patient Safety, Phosphoproteins, Piperazines, Pyridines, RNA Splicing Factors, Treatment Outcome
Abstract

We conducted a phase I clinical trial of H3B-8800, an oral small molecule that binds Splicing Factor 3B1 (SF3B1), in patients with MDS, CMML, or AML. Among 84 enrolled patients (42 MDS, 4 CMML and 38 AML), 62 were red blood cell (RBC) transfusion dependent at study entry. Dose escalation cohorts examined two once-daily dosing regimens: schedule I (5 days on/9 days off, range of doses studied 1-40 mg, n = 65) and schedule II (21 days on/7 days off, 7-20 mg, n = 19); 27 patients received treatment for ≥180 days. The most common treatment-related, treatment-emergent adverse events included diarrhea, nausea, fatigue, and vomiting. No complete or partial responses meeting IWG criteria were observed; however, RBC transfusion free intervals >56 days were observed in nine patients who were transfusion dependent at study entry (15%). Of 15 MDS patients with missense SF3B1 mutations, five experienced RBC transfusion independence (TI). Elevated pre-treatment expression of aberrant transcripts of Transmembrane Protein 14C (TMEM14C), an SF3B1 splicing target encoding a mitochondrial porphyrin transporter, was observed in MDS patients experiencing RBC TI. In summary, H3B-8800 treatment was associated with mostly low-grade TAEs and induced RBC TI in a biomarker-defined subset of MDS.

Published
2021

8. Whole Exome Sequencing Identifies a Novel Homozygous Missense Mutation in the CSB Protein-Encoding ERCC6 Gene in a Taiwanese Boy with Cockayne Syndrome.

Author

Lin, Ching-Ming, Yang, Jay-How, Lee, Hwei-Jen, Lin, Yu-Pang, Tsai, Li-Ping, Hsu, Chih-Sin, Luxton, G, and Hu, Chih-Fen

Subjects
Cockayne syndrome B, ERCC6, progeroid, transcription-coupled nucleotide excision repair (TC-NER), whole exome sequencing
Abstract

BACKGROUND: Cockayne syndrome (CS) is a rare form of dwarfism that is characterized by progressive premature aging. CS is typically caused by mutations in the excision repair cross-complementing protein group 6 (ERCC6) gene that encodes the CS group B (CSB) protein. Using whole exome sequencing, we recently identified a novel homozygous missense mutation (Leu536Trp) in CSB in a Taiwanese boy with CS. Since the current database (Varsome) interprets this variant as likely pathogenic, we utilized a bioinformatic tool to investigate the impact of Leu536Trp as well as two other variants (Arg453Ter, Asp532Gly) in similar articles on the CSB protein structure stability. METHODS: We used iterative threading assembly refinement (I-TASSER) to generate a predictive 3D structure of CSB. We calculated the change of mutation energy after residues substitution on the protein stability using I-TASSER as well as the artificial intelligence program Alphafold. RESULTS: The Asp532Gly variant destabilized both modeled structures, while the Leu536Trp variant showed no effect on I-TASSERs model but destabilized the Alphafolds modeled structure. CONCLUSIONS: We propose here the first case of CS associated with a novel homozygous missense mutation (Leu536Trp) in CSB. Furthermore, we suggest that the Asp532Gly and Leu536Trp variants are both pathogenic after bioinformatic analysis of protein stability.

Published
2021

9. Observation of substrate diffusion and ligand binding in enzyme crystals using high-repetition-rate mix-and-inject serial crystallography

Author

Pandey, Suraj, Calvey, George, Katz, Andrea M, Malla, Tek Narsingh, Koua, Faisal HM, Martin-Garcia, Jose M, Poudyal, Ishwor, Yang, Jay-How, Vakili, Mohammad, Yefanov, Oleksandr, Zielinski, Kara A, Bajt, Sasa, Awel, Salah, Doerner, Katarina, Frank, Matthias, Gelisio, Luca, Jernigan, Rebecca, Kirkwood, Henry, Kloos, Marco, Koliyadu, Jayanath, Mariani, Valerio, Miller, Mitchell D, Mills, Grant, Nelson, Garrett, Olmos, Jose L, Sadri, Alireza, Sato, Tokushi, Tolstikova, Alexandra, Xu, Weijun, Ourmazd, Abbas, Spence, John CH, Schwander, Peter, Barty, Anton, Chapman, Henry N, Fromme, Petra, Mancuso, Adrian P, Phillips, George N, Bean, Richard, Pollack, Lois, and Schmidt, Marius

Subjects
Tuberculosis, Rare Diseases, Good Health and Well Being, substrate diffusion in crystals, antibiotic resistance, beta-lactamases, enzyme kinetics, irreversible inhibition, mix-and-inject serial crystallography, serial femtosecond crystallography, European X-ray Free-Electron Laser, megahertz pulse-repetition rate, protein structure determination, drug discovery, ceftriaxone, sulbactam, X-ray crystallography, enzyme mechanisms, β-lactamases, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Condensed Matter Physics, Physical Chemistry (incl. Structural)
Abstract

Here, we illustrate what happens inside the catalytic cleft of an enzyme when substrate or ligand binds on single-millisecond timescales. The initial phase of the enzymatic cycle is observed with near-atomic resolution using the most advanced X-ray source currently available: the European XFEL (EuXFEL). The high repetition rate of the EuXFEL combined with our mix-and-inject technology enables the initial phase of ceftriaxone binding to the Mycobacterium tuberculosis β-lactamase to be followed using time-resolved crystallography in real time. It is shown how a diffusion coefficient in enzyme crystals can be derived directly from the X-ray data, enabling the determination of ligand and enzyme-ligand concentrations at any position in the crystal volume as a function of time. In addition, the structure of the irreversible inhibitor sulbactam bound to the enzyme at a 66 ms time delay after mixing is described. This demonstrates that the EuXFEL can be used as an important tool for biomedically relevant research.

Published
2021

14. Author Correction: Membrane protein megahertz crystallography at the European XFEL

Author

Gisriel, Chris, Coe, Jesse, Letrun, Romain, Yefanov, Oleksandr M, Luna-Chavez, Cesar, Stander, Natasha E, Lisova, Stella, Mariani, Valerio, Kuhn, Manuela, Aplin, Steve, Grant, Thomas D, Dörner, Katerina, Sato, Tokushi, Echelmeier, Austin, Villarreal, Jorvani Cruz, Hunter, Mark S, Wiedorn, Max O, Knoska, Juraj, Mazalova, Victoria, Roy-Chowdhury, Shatabdi, Yang, Jay-How, Jones, Alex, Bean, Richard, Bielecki, Johan, Kim, Yoonhee, Mills, Grant, Weinhausen, Britta, Meza, Jose D, Al-Qudami, Nasser, Bajt, Saša, Brehm, Gerrit, Botha, Sabine, Boukhelef, Djelloul, Brockhauser, Sandor, Bruce, Barry D, Coleman, Matthew A, Danilevski, Cyril, Discianno, Erin, Dobson, Zachary, Fangohr, Hans, Martin-Garcia, Jose M, Gevorkov, Yaroslav, Hauf, Steffen, Hosseinizadeh, Ahmad, Januschek, Friederike, Ketawala, Gihan K, Kupitz, Christopher, Maia, Luis, Manetti, Maurizio, Messerschmidt, Marc, Michelat, Thomas, Mondal, Jyotirmoy, Ourmazd, Abbas, Previtali, Gianpietro, Sarrou, Iosifina, Schön, Silvan, Schwander, Peter, Shelby, Megan L, Silenzi, Alessandro, Sztuk-Dambietz, Jolanta, Szuba, Janusz, Turcato, Monica, White, Thomas A, Wrona, Krzysztof, Xu, Chen, Abdellatif, Mohamed H, Zook, James D, Spence, John CH, Chapman, Henry N, Barty, Anton, Kirian, Richard A, Frank, Matthias, Ros, Alexandra, Schmidt, Marius, Fromme, Raimund, Mancuso, Adrian P, Fromme, Petra, and Zatsepin, Nadia A

Subjects
Biochemistry and Cell Biology, Biological Sciences
Abstract

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Published
2020

15. Olutasidenib alone or with azacitidine in IDH1-mutated acute myeloid leukaemia and myelodysplastic syndrome: phase 1 results of a phase 1/2 trial

Author

Watts, Justin M, Baer, Maria R, Yang, Jay, Prebet, Thomas, Lee, Sangmin, Schiller, Gary J, Dinner, Shira N, Pigneux, Arnaud, Montesinos, Pau, Wang, Eunice S, Seiter, Karen P, Wei, Andrew H, De Botton, Stephane, Arnan, Montserrat, Donnellan, Will, Schwarer, Anthony P, Récher, Christian, Jonas, Brian A, Ferrell, P Brent, Jr, Marzac, Christophe, Kelly, Patrick, Sweeney, Jennifer, Forsyth, Sanjeev, Guichard, Sylvie M, Brevard, Julie, Henrick, Patrick, Mohamed, Hesham, and Cortes, Jorge E

Published
2023
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16. Membrane protein megahertz crystallography at the European XFEL

Author

Gisriel, Chris, Coe, Jesse, Letrun, Romain, Yefanov, Oleksandr M, Luna-Chavez, Cesar, Stander, Natasha E, Lisova, Stella, Mariani, Valerio, Kuhn, Manuela, Aplin, Steve, Grant, Thomas D, Dörner, Katerina, Sato, Tokushi, Echelmeier, Austin, Cruz Villarreal, Jorvani, Hunter, Mark S, Wiedorn, Max O, Knoska, Juraj, Mazalova, Victoria, Roy-Chowdhury, Shatabdi, Yang, Jay-How, Jones, Alex, Bean, Richard, Bielecki, Johan, Kim, Yoonhee, Mills, Grant, Weinhausen, Britta, Meza, Jose D, Al-Qudami, Nasser, Bajt, Saša, Brehm, Gerrit, Botha, Sabine, Boukhelef, Djelloul, Brockhauser, Sandor, Bruce, Barry D, Coleman, Matthew A, Danilevski, Cyril, Discianno, Erin, Dobson, Zachary, Fangohr, Hans, Martin-Garcia, Jose M, Gevorkov, Yaroslav, Hauf, Steffen, Hosseinizadeh, Ahmad, Januschek, Friederike, Ketawala, Gihan K, Kupitz, Christopher, Maia, Luis, Manetti, Maurizio, Messerschmidt, Marc, Michelat, Thomas, Mondal, Jyotirmoy, Ourmazd, Abbas, Previtali, Gianpietro, Sarrou, Iosifina, Schön, Silvan, Schwander, Peter, Shelby, Megan L, Silenzi, Alessandro, Sztuk-Dambietz, Jolanta, Szuba, Janusz, Turcato, Monica, White, Thomas A, Wrona, Krzysztof, Xu, Chen, Abdellatif, Mohamed H, Zook, James D, Spence, John CH, Chapman, Henry N, Barty, Anton, Kirian, Richard A, Frank, Matthias, Ros, Alexandra, Schmidt, Marius, Fromme, Raimund, Mancuso, Adrian P, Fromme, Petra, and Zatsepin, Nadia A

Subjects
Biochemistry and Cell Biology, Biological Sciences, 1.1 Normal biological development and functioning, Underpinning research, Generic health relevance, Crystallography, Cyanobacteria, Electrons, Lasers, Membrane Proteins, Models, Molecular, Photosystem I Protein Complex, Static Electricity, Synchrotrons, Thermosynechococcus, X-Rays
Abstract

The world's first superconducting megahertz repetition rate hard X-ray free-electron laser (XFEL), the European XFEL, began operation in 2017, featuring a unique pulse train structure with 886 ns between pulses. With its rapid pulse rate, the European XFEL may alleviate some of the increasing demand for XFEL beamtime, particularly for membrane protein serial femtosecond crystallography (SFX), leveraging orders-of-magnitude faster data collection. Here, we report the first membrane protein megahertz SFX experiment, where we determined a 2.9 Å-resolution SFX structure of the large membrane protein complex, Photosystem I, a > 1 MDa complex containing 36 protein subunits and 381 cofactors. We address challenges to megahertz SFX for membrane protein complexes, including growth of large quantities of crystals and the large molecular and unit cell size that influence data collection and analysis. The results imply that megahertz crystallography could have an important impact on structure determination of large protein complexes with XFELs.

Published
2019

18. EZH2 inhibitor tazemetostat in patients with relapsed or refractory, BAP1-inactivated malignant pleural mesothelioma: a multicentre, open-label, phase 2 study

Author

Zauderer, Marjorie G, Szlosarek, Peter W, Le Moulec, Sylvestre, Popat, Sanjay, Taylor, Paul, Planchard, David, Scherpereel, Arnaud, Koczywas, Marianna, Forster, Martin, Cameron, Robert B, Peikert, Tobias, Argon, Evren Kocabaş, Michaud, Neil R, Szanto, Attila, Yang, Jay, Chen, Yingxue, Kansra, Vikram, Agarwal, Shefali, and Fennell, Dean A

Published
2022
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21. Multi-institutional study evaluating clinical outcome with allogeneic hematopoietic stem cell transplantation after blinatumomab in patients with B-cell acute lymphoblastic leukemia: real-world data

Author

Badar, Talha, Szabo, Aniko, Litzow, Mark, Burkart, Madelyn, Yurkiewicz, Ilana, Dinner, Shira, Hefazi, Mehrdad, Shallis, Rory M., Podoltsev, Nikolai, Patel, Anand A., Curran, Emily, Wadleigh, Martha, Balasubramanian, Suresh, Yang, Jay, Arslan, Shukaib, Aldoss, Ibrahim, Mattison, Ryan, Cenin, Danielle, Siebenaller, Caitlin, Advani, Anjali, Liedtke, Michaela, and Atallah, Ehab

Published
2021
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22. Tazemetostat for patients with relapsed or refractory follicular lymphoma: an open-label, single-arm, multicentre, phase 2 trial

Author

Morschhauser, Franck, Tilly, Hervé, Chaidos, Aristeidis, McKay, Pamela, Phillips, Tycel, Assouline, Sarit, Batlevi, Connie Lee, Campbell, Phillip, Ribrag, Vincent, Damaj, Gandhi Laurent, Dickinson, Michael, Jurczak, Wojciech, Kazmierczak, Maciej, Opat, Stephen, Radford, John, Schmitt, Anna, Yang, Jay, Whalen, Jennifer, Agarwal, Shefali, Adib, Deyaa, and Salles, Gilles

Published
2020
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38. A Normalization Protocol Reduces Edge Effect in High-Throughput Analyses of Hydroxyurea Hypersensitivity in Fission Yeast.

Author

Lam, Ulysses Tsz-Fung, Nguyen, Thi Thuy Trang, Raechell, Raechell, Yang, Jay, Singer, Harry, and Chen, Ee Sin

Subjects
HYDROXYUREA, YEAST, HIGH throughput screening (Drug development), MICROBIAL genes, GENE knockout
Abstract

Edge effect denotes better growth of microbial organisms situated at the edge of the solid agar media. Although the precise reason underlying edge effect is unresolved, it is generally attributed to greater nutrient availability with less competing neighbors at the edge. Nonetheless, edge effect constitutes an unavoidable confounding factor that results in misinterpretation of cell fitness, especially in high-throughput screening experiments widely employed for genome-wide investigation using microbial gene knockout or mutant libraries. Here, we visualize edge effect in high-throughput high-density pinning arrays and report a normalization approach based on colony growth rate to quantify drug (hydroxyurea)-hypersensitivity in fission yeast strains. This normalization procedure improved the accuracy of fitness measurement by compensating cell growth rate discrepancy at different locations on the plate and reducing false-positive and -negative frequencies. Our work thus provides a simple and coding-free solution for a struggling problem in robotics-based high-throughput screening experiments. [ABSTRACT FROM AUTHOR]

Published
2023
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46. Modular droplet injector for sample conservation providing new structural insight for the conformational heterogeneity in the disease-associated NQO1 enzyme.

Author

Doppler, Diandra, Sonker, Mukul, Egatz-Gomez, Ana, Grieco, Alice, Zaare, Sahba, Jernigan, Rebecca, Meza-Aguilar, Jose Domingo, Rabbani, Mohammad T., Manna, Abhik, Alvarez, Roberto C., Karpos, Konstantinos, Cruz Villarreal, Jorvani, Nelson, Garrett, Yang, Jay-How, Carrion, Jackson, Morin, Katherine, Ketawala, Gihan K., Pey, Angel L., Ruiz-Fresneda, Miguel Angel, and Pacheco-Garcia, Juan Luis

Subjects
FREE electron lasers, ALZHEIMER'S disease, DRUG discovery, PROTEIN fractionation, INJECTORS, QUINONE
Abstract

Droplet injection strategies are a promising tool to reduce the large amount of sample consumed in serial femtosecond crystallography (SFX) measurements at X-ray free electron lasers (XFELs) with continuous injection approaches. Here, we demonstrate a new modular microfluidic droplet injector (MDI) design that was successfully applied to deliver microcrystals of the human NAD(P)H:quinone oxidoreductase 1 (NQO1) and phycocyanin. We investigated droplet generation conditions through electrical stimulation for both protein samples and implemented hardware and software components for optimized crystal injection at the Macromolecular Femtosecond Crystallography (MFX) instrument at the Stanford Linac Coherent Light Source (LCLS). Under optimized droplet injection conditions, we demonstrate that up to 4-fold sample consumption savings can be achieved with the droplet injector. In addition, we collected a full data set with droplet injection for NQO1 protein crystals with a resolution up to 2.7 Å, leading to the first room-temperature structure of NQO1 at an XFEL. NQO1 is a flavoenzyme associated with cancer, Alzheimer's and Parkinson's disease, making it an attractive target for drug discovery. Our results reveal for the first time that residues Tyr128 and Phe232, which play key roles in the function of the protein, show an unexpected conformational heterogeneity at room temperature within the crystals. These results suggest that different substates exist in the conformational ensemble of NQO1 with functional and mechanistic implications for the enzyme's negative cooperativity through a conformational selection mechanism. Our study thus demonstrates that microfluidic droplet injection constitutes a robust sample-conserving injection method for SFX studies on protein crystals that are difficult to obtain in amounts necessary for continuous injection, including the large sample quantities required for time-resolved mix-and-inject studies. [ABSTRACT FROM AUTHOR]

Published
2023
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