21 results on '"Aurelius O"'
Search Results
2. DexyHemoglobin structure from serial synchrotron crystallography with fixed target
- Author
-
Bjelcic, M., primary, Sigfridsson Clauss, K., additional, Aurelius, O., additional, Milas, M., additional, Nan, J., additional, and Ursby, T., additional
- Published
- 2023
- Full Text
- View/download PDF
3. Determination of the structure of active tyrosinase from bacterium Verrucomicrobium spinosum
- Author
-
Fekry, M., primary, Dave, K., additional, Badgujar, D., additional, Aurelius, O., additional, Hamnevik, E., additional, Dobritzsch, D., additional, and Danielson, H., additional
- Published
- 2023
- Full Text
- View/download PDF
4. MicroMAX at the MAX IV Laboratory: macromolecular crystallography in northern Europe is heating up
- Author
-
Aurelius, O., primary, Milas, M., additional, Chenchiliyan, M., additional, Yazdi-Rizi, M., additional, Cehovin, A., additional, Nan, J., additional, Gorgisyan, I., additional, Bjelčić, M., additional, Benedictsson, S., additional, Roslund, L., additional, Jagudin, E., additional, Eguiraun, M., additional, Nardella, A., additional, Finke, A., additional, Krojer, T., additional, Gonzalez, A., additional, and Ursby, T., additional
- Published
- 2023
- Full Text
- View/download PDF
5. First Indicator of Relapse in Testicular Cancer and Implications for Follow-up: Analysis of the Swiss Austrian German Testicular Cancer Cohort Study (SAG TCCS)
- Author
-
Stefanie Fischer, Silke Gillessen, Odile Stalder, Angelika Terbuch, Richard Cathomas, Florian A. Schmid, Deborah Zihler, Beat Müller, Christian D. Fankhauser, Anita Hirschi-Blickenstorfer, Luis Alex Kluth, Bettina Seifert, Arnoud J. Templeton, Walter Mingrone, Mark-Peter Ufe, Natalie Fischer, Jörg Beyer, Regina Woelky, Aurelius Omlin, Ursula Vogl, Katharina Hoppe, Jörn Kamradt, Sacha I. Rothschild, and Christian Rothermundt
- Subjects
Testicular cancer ,Follow-up ,Germ cell tumours ,Diseases of the genitourinary system. Urology ,RC870-923 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background and objective: Follow-up for patients with testicular cancer should ensure early detection of relapses. Optimal schedules and minimum requirements for cross-sectional imaging are not clearly defined, and guideline recommendations differ. Our aim was to analyse the clinical impact of different imaging modalities for detection of relapse in a large prospective cohort (Swiss Austrian German Testicular Cancer Cohort Study, SAG TCCS). Methods: Patients with seminoma or nonseminoma were prospectively enrolled between January 2014 and February 2023 after initial treatment (n = 1175). Follow-up according to the study schedule was individualised for histology and disease stage. Only patients who had received primary treatment were considered. We analysed the total number of imaging modalities and scans identifying relapse and the timing of relapse. Key findings and limitations: We analysed data for 1006 patients (64% seminoma, 36% nonseminoma); 76% had stage I disease. Active surveillance was the most frequent management strategy (65%). Recurrence occurred in 82 patients, corresponding to a 5-yr relapse-free survival rate of 90.1% (95% confidence interval 87.7–92.1%). Median follow-up for patients without relapse was 38.4 mo (interquartile range 21.6–61.0). Cross-sectional imaging of the abdomen was the most important indicator of relapse 57%, abdominal CT accounting for 46% and MRI for 11%. Marker elevation indicated relapse in 24% of cases. Chest X-ray was the least useful modality, indicating relapse in just 2% of cases. Conclusions and clinical implications: On the basis of findings from our prospective register, we have adapted follow-up schedules with an emphasis on abdominal imaging and a reduction in chest X-rays. These schedules might provide additional guidance for clinicians and will be prospectively evaluated as SAG TCCS continues to enrol patients. Patient summary: We analysed the value of different types of imaging scans for detection of relapse of testicular cancer. We used our findings to propose an optimum follow-up schedule for patients with testicular cancer.
- Published
- 2024
- Full Text
- View/download PDF
6. XFEL structure of Class Ib ribonucleotide reductase dimanganese(II) NrdF in complex with oxidized NrdI from Bacillus cereus
- Author
-
John, J., primary, Lebrette, H., additional, Aurelius, O., additional, and Hogbom, M., additional
- Published
- 2022
- Full Text
- View/download PDF
7. XFEL structure of Class Ib ribonucleotide reductase dimanganese(II) NrdF in complex with hydroquinone NrdI from Bacillus cereus
- Author
-
John, J., primary, Lebrette, H., additional, Aurelius, O., additional, and Hogbom, M., additional
- Published
- 2022
- Full Text
- View/download PDF
8. Optimization of capillary-based serial synchrotron crystallography sample delivery for soluble proteins
- Author
-
Bjelcic, M., primary, Aurelius, O., additional, Nan, J., additional, Ghosh, S., additional, Neutze, R., additional, and Ursby, T., additional
- Published
- 2022
- Full Text
- View/download PDF
9. Patient and General Population Preferences Regarding the Benefits and Harms of Treatment for Metastatic Prostate Cancer: A Discrete Choice Experiment
- Author
-
Dominik Menges, Michela C. Piatti, Aurelius Omlin, Richard Cathomas, Daniel Benamran, Stefanie Fischer, Christophe Iselin, Marc Küng, Anja Lorch, Lukas Prause, Christian Rothermundt, Alix O'Meara Stern, Deborah Zihler, Max Lippuner, Julia Braun, Thomas Cerny, and Milo A. Puhan
- Subjects
Adverse effects ,Benefit ,Benefit-harm assessment ,Discrete choice experiment ,Harm ,Metastasis ,Diseases of the genitourinary system. Urology ,RC870-923 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background: Patient preferences for treatment outcomes are important to guide decision-making in clinical practice, but little is known about the preferences of patients with metastatic hormone-sensitive prostate cancer (mHSPC). Objective: To evaluate patient preferences regarding the attributed benefits and harms of systemic treatments for mHSPC and preference heterogeneity between individuals and specific subgroups. Design, setting, and participants: We conducted an online discrete choice experiment (DCE) preference survey among 77 patients with metastatic prostate cancer (mPC) and 311 men from the general population in Switzerland between November 2021 and August 2022. Outcome measurements and statistical analysis: We evaluated preferences and preference heterogeneity related to survival benefits and treatment-related adverse effects using mixed multinomial logit models and estimated the maximum survival time participants were willing to trade to avert specific adverse effects. We further assessed characteristics associated with different preference patterns via subgroup and latent class analyses. Results and limitations: Patients with mPC showed an overall stronger preference for survival benefits in comparison to men from the general population (p = 0.004), with substantial preference heterogeneity between individuals within the two samples (both p
- Published
- 2023
- Full Text
- View/download PDF
10. Development and Validation of an Inflammatory Prognostic Index to Predict Outcomes in Advanced/Metastatic Urothelial Cancer Patients Receiving Immune Checkpoint Inhibitors
- Author
-
Sara Mokbel, Giuilia Baciarello, Pernelle Lavaud, Aurelius Omlin, Fabio Calabrò, Richard Cathomas, Stefanie Aeppli, Pauline Parent, Patrizia Giannatempo, Kira-Lee Koster, Naara Appel, Philippe Gonnet, Gesuino Angius, Petros Tsantoulis, Hendrick-Tobias Arkenau, Carlo Cattrini, Carlo Messina, Jean Zeghondy, Cristina Morelli, Yohann Loriot, Vincenzo Formica, and Anna Patrikidou
- Subjects
immune checkpoint inhibitors ,advanced/metastatic urothelial cancer ,inflammatory markers ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background: Immune checkpoint inhibitors (ICIs) improve overall survival (OS) in advanced/metastatic urothelial cancer (a/mUC) patients. Preliminary evidence suggests a prognostic role of inflammatory biomarkers in this setting. We aimed to develop a disease-specific prognostic inflammatory index for a/mUC patients on ICIs. Methods: Fifteen variables were retrospectively correlated with OS and progression-free survival (PFS) in a development (D, n = 264) and a validation (V, n = 132) cohort of platinum-pretreated a/mUC pts receiving ICIs at L2 or further line. A nomogram and inflammatory prognostic index (U-IPI) were developed. The index was also tested in a control cohort of patients treated with chemotherapy only (C, n = 114). Results: The strongest predictors of OS were baseline platelet/lymphocyte (PLR) and neutrophil/lymphocyte (NLR) ratios, and lactate dehydrogenase (LDH), NLR, and albumin changes at 4 weeks. These were used to build the U-IPI, which can distinctly classify patients into good or poor response groups. The nomogram scoring is significant for PFS and OS (p < 0.001 in the D, V, and combined cohorts) for the immunotherapy (IO) cohort, but not for the control cohort. Conclusions: The lack of a baseline systemic inflammatory profile and the absence of early serum inflammatory biomarker changes are associated with significantly better outcomes on ICIs in a/mUC pts. The U-IPI is an easily applicable dynamic prognostic tool for PFS and OS, allowing for the early identification of a sub-group with dismal outcomes that would not benefit from ICIs, while distinguishing another that draws an important benefit.
- Published
- 2024
- Full Text
- View/download PDF
11. Interdisciplinary Swiss consensus recommendations on staging and treatment of advanced prostate cancer
- Author
-
Arnoud J. Templeton, Aurelius Omlin, Dominik Berthold, Jörg Beyer, Irene A. Burger, Daniel Eberli, Daniel Engeler, Christian Fankhauser, Stefanie Fischer, Silke Gillessen, Guillaume Nicolas, Stephanie Kroeze, Anja Lorch, Michael Müntener, Alexandros Papachristofilou, Niklaus Schaefer, Daniel Seiler, Frank Stenner, Petros Tsantoulis, Tatjana Vlajnic, Thomas Zilli, Daniel Zwahlen, and Richard Cathomas
- Subjects
Medicine - Abstract
The management of prostate cancer is undergoing rapid changes in all disease settings. Novel imaging tools for diagnosis have been introduced, and the treatment of high-risk localized, locally advanced and metastatic disease has changed considerably in recent years. From clinical and health-economic perspectives, a rational and optimal use of the available options is of the utmost importance. While international guidelines list relevant pivotal trials and give recommendations for a variety of clinical scenarios, there is much room for interpretation, and several important questions remain highly debated. The goal of developing a national consensus on the use of these novel diagnostic and therapeutic strategies in order to improve disease management and eventually patient outcomes has prompted a Swiss consensus meeting. Experts from several specialties, including urology, medical oncology, radiation oncology, pathology and nuclear medicine, discussed and voted on questions of the current most important areas of uncertainty, including the staging and treatment of high-risk localized disease, treatment of metastatic hormone-sensitive prostate cancer (mHSPC) and use of new options to treat metastatic castration-resistant prostate cancer (mCRPC).
- Published
- 2023
- Full Text
- View/download PDF
12. Novel sequential treatment strategy for patients with muscle-invasive bladder cancer (MIBC): intravesical recombinant BCG, followed by neoadjuvant chemoimmunotherapy, radical cystectomy plus pelvic lymphadenectomy and adjuvant immunotherapy – protocol of a multicentre, single arm phase 2 trial (SAKK 06/19)
- Author
-
Richard Cathomas, Ulf Petrausch, Aurelius Omlin, Stefanie Hayoz, Martin Spahn, Martina Schneider, Cyrill A Rentsch, and Sacha Rothschild
- Subjects
Medicine - Abstract
Introduction The combination of checkpoint inhibition and cisplatin-based chemotherapy is investigated in muscle invasive bladder cancer (MIBC) and results from phase 2 trials have been presented. Intravesical BCG has been used for non-MIBC (NMIBC) in patients with carcinoma in situ and high-grade Ta/T1 tumours. BCG induces innate and adapted immune response and upregulation of PD-L1 in preclinical models. The proposed trial is intended to implement a new immuno-immuno-chemotherapy induction therapy for MIBC. The combination of BCG and checkpoint inhibition with chemotherapy aims at higher intravesical responses and better local and systemic control of disease.Methods and analysis SAKK 06/19 is an open-label single-arm phase II trial for patients with resectable MIBC T2-T4a cN0-1. Intravesical recombinant BCG (rBCG: VPM1002BC) is applied weekly for three instillations followed by four cycles of neoadjuvant cisplatin/gemcitabine every 3 weeks. Atezolizumab 1200 mg every 3 weeks is started together with rBCG and given for four cycles. All patients then undergo restaging and radical cystectomy and pelvic lymphadenectomy. Atezolizumab is continued as maintenance therapy after surgery every 3 weeks for 13 cycles. Pathological complete remission is the primary endpoint. Secondary endpoints include pathological response rate (
- Published
- 2023
- Full Text
- View/download PDF
13. Toxicity Characteristics Leaching Procedure of Wastes dumped in some part of Federal Capital Territory Abuja, North Central Nigeria
- Author
-
johnson arogundade and Aurelius Omali Sr.
- Subjects
Technology ,Science - Abstract
The solid wastes in some waste disposal facilities within Federal Capital Territory, Abuja Nigeria were assessed. They were assessed to know whether they are characteristically hazardous to the environment where they are dumped. The procedure became necessary because the solid wastes in the study are known not to be sorted before disposal. Sorting is needed to separate the hazardous components from non-hazardous components of the solid wastes before they are disposed. The assessment was done in accordance with Resource Conservation and Recovery Act, (RCRA, 1976) of United State Environmental Protection Agency using Toxicity Characteristics Leaching procedure. The procedure shows that the Chromium (Cr) ranges from 3.03mg/L to 11mg/L across the investigated dumpsites, Lead (Pb) ranges from 1.58mg/L to 47.6mg/L across the investigated dumpsites and Cadmium (Cd) ranges from 0.169mg/L to 19.2mg/L across the investigated dumpsites. It can be deduced from the results that the wastes in the investigated dump facilities are characteristically hazardous because the concentration of RCRA metals (Pb, Cr and Cd) are above the USEPA allowable limits.
- Published
- 2023
- Full Text
- View/download PDF
14. IRONMAN: A Novel International Registry of Men With Advanced Prostate Cancer
- Author
-
Lorelei A. Mucci, Jacob Vinson, Theresa Gold, Travis Gerke, Julie Filipenko, Rebecca M. Green, Simon G. Anderson, Simone Badal, Anders Bjartell, Kim N. Chi, Ian D. Davis, Deborah Enting, André P. Fay, John Lazarus, Joaquin Mateo, Ray McDermott, Folakemi T. Odedina, David Olmos, Aurelius Omlin, Ademola A. Popoola, Camille Ragin, Robin Roberts, Kjell M. Russnes, Charles Waihenya, Konrad H. Stopsack, Terry Hyslop, Paul Villanti, Philip W. Kantoff, and Daniel J. George
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
PURPOSETo describe a newly established international registry recruiting diverse patients with advanced prostate cancer across academic and community practices to address unmet needs in this population.PATIENTS AND METHODSInitiated in 2017, IRONMAN (International Registry for Men with Advanced Prostate Cancer) is a prospective cohort of patients with advanced prostate cancer. The study will enroll 5,000 patients with metastatic hormone-sensitive prostate cancer (mHSPC) or castration-resistant prostate cancer (CRPC), recruited from Australia, the Bahamas, Barbados, Brazil, Canada, Ireland, Jamaica, Kenya, Nigeria, Norway, South Africa, Spain, Sweden, Switzerland, the United Kingdom, and the United States. The study is collecting datatypes to study variation in care and treatment of advanced prostate cancer across countries and across academic, community-based, and government practices with a focus on clinical outcomes, patient-reported outcomes, epidemiologic data, biologic subtypes, and clinician questionnaires.RESULTSThrough July 2022, 2,682 eligible patients were enrolled in 11 of 12 active countries. Sixty-six percent of patients have mHSPC, and 34% have CRPC. On the basis of self-report, 11% of patients are Black and 9% are Hispanic. Five Veterans Affairs Medical Centers are enrolling patients. Globally, 23% of patients report being veterans of military service.CONCLUSIONTo our knowledge, this is the first international cohort of people newly diagnosed with advanced prostate cancer designed to describe variations in patient management, experiences, and outcomes. IRONMAN aims to identify optimal treatment sequences to improve survival, understand patient-reported outcomes, and explore novel biomarkers to understand treatment resistance mechanisms. Insights from IRONMAN will inform and guide future clinical management of people with mHSPC and CRPC. This cohort study will provide real-world evidence to facilitate a better understanding of the survivorship of people with advanced prostate cancer.
- Published
- 2022
- Full Text
- View/download PDF
15. Incidence and outcome of patients with renal cell carcinoma treated with partial or radical nephrectomy in the Cantons St Gallen and Appenzell 2009–2018
- Author
-
Stefanie Aeppli, Daniel S. Engeler, Stefanie Fischer, Aurelius Omlin, Manolis Pratsinis, Christian Hermann, and Christian Rothermundt
- Subjects
Medicine - Abstract
BACKGROUND: Over recent years, the incidence of renal cell carcinoma (RCC) has remained unchanged in Switzerland and is low compared with other European countries. Partial or radical nephrectomy is the mainstay of treatment in patients with localised disease. METHODS: We conducted an analysis of data from the cancer registry of Eastern Switzerland on patients with surgery for RCC from 2009 to 2018, focusing on a comparison of surgical technique and outcome in tertiary and non-tertiary hospitals. RESULTS: 492 nephrectomies were performed. Out of 441 curative procedures, 226 were radical and 195 partial nephrectomies (20 unknown). At the tertiary hospital, statistically significantly more partial nephrectomies were performed in non-metastatic patients than at non-tertiary hospitals. We demonstrate a trend towards better disease-free survival after partial compared with radical nephrectomy. The 5-year overall survival for patients diagnosed between 2009 and 2013 was 85%, 83%, and 70% in stage I, II, and III, respectively, compared with 96%, 78%, and 72% for patients diagnosed between 2014 and 2018. CONCLUSION: RCC incidence in Switzerland has been stable during the past decade in contrast to other European countries, and no stage migration occurred. We demonstrated that patients with localised renal cancer at our tertiary centre were more likely to be treated with renal preserving surgery compared with non-tertiary hospitals. This analysis underlines the importance of local cancer registries in the comparison of treatment and outcome over time.
- Published
- 2022
- Full Text
- View/download PDF
16. Room-temperature serial synchrotron crystallography structure of Spinacia oleracea RuBisCO.
- Author
-
Bjelčić M, Aurelius O, Nan J, Neutze R, and Ursby T
- Subjects
- Crystallography, X-Ray methods, Temperature, Protein Conformation, Spinacia oleracea enzymology, Spinacia oleracea chemistry, Ribulose-Bisphosphate Carboxylase chemistry, Ribulose-Bisphosphate Carboxylase metabolism, Synchrotrons, Models, Molecular
- Abstract
Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is the enzyme responsible for the first step of carbon dioxide (CO
2 ) fixation in plants, which proceeds via the carboxylation of ribulose 1,5-biphosphate. Because of the enormous importance of this reaction in agriculture and the environment, there is considerable interest in the mechanism of fixation of CO2 by RuBisCO. Here, a serial synchrotron crystallography structure of spinach RuBisCO is reported at 2.3 Å resolution. This structure is consistent with earlier single-crystal X-ray structures of this enzyme and the results are a good starting point for a further push towards time-resolved serial synchrotron crystallography in order to better understand the mechanism of the reaction., (open access.)- Published
- 2024
- Full Text
- View/download PDF
17. Anaerobic fixed-target serial crystallography using sandwiched silicon nitride membranes.
- Author
-
Bjelčić M, Sigfridsson Clauss KGV, Aurelius O, Milas M, Nan J, and Ursby T
- Subjects
- Crystallography, Anaerobiosis, Crystallography, X-Ray, Macromolecular Substances, Synchrotrons, Oxygen
- Abstract
In recent years, the emergence of serial crystallography, initially pioneered at X-ray free-electron lasers (XFELs), has sparked a growing interest in collecting macromolecular crystallographic data at room temperature. Various fixed-target serial crystallography techniques have been developed, ranging from commercially available chips to in-house designs implemented at different synchrotron facilities. Nevertheless, there is currently no commercially available chip (known to the authors) specifically designed for the direct handling of oxygen-sensitive samples. This study presents a methodology employing silicon nitride chips arranged in a `sandwich' configuration, enabling reliable room-temperature data collection from oxygen-sensitive samples. The method involves the utilization of a custom-made 3D-printed assembling tool and a MX sample holder. To validate the effectiveness of the proposed method, deoxyhemoglobin and methemoglobin samples were investigated using the BioMAX X-ray macromolecular crystallography beamline, the Balder X-ray absorption spectroscopy beamline and UV-Vis absorption spectroscopy., (open access.)
- Published
- 2023
- Full Text
- View/download PDF
18. Structure of a ribonucleotide reductase R2 protein radical.
- Author
-
Lebrette H, Srinivas V, John J, Aurelius O, Kumar R, Lundin D, Brewster AS, Bhowmick A, Sirohiwal A, Kim IS, Gul S, Pham C, Sutherlin KD, Simon P, Butryn A, Aller P, Orville AM, Fuller FD, Alonso-Mori R, Batyuk A, Sauter NK, Yachandra VK, Yano J, Kaila VRI, Sjöberg BM, Kern J, Roos K, and Högbom M
- Subjects
- Electron Transport, Protons, Crystallography, X-Ray methods, Catalytic Domain, Ribonucleotide Reductases chemistry, Entomoplasmataceae enzymology, Bacterial Proteins chemistry
- Abstract
Aerobic ribonucleotide reductases (RNRs) initiate synthesis of DNA building blocks by generating a free radical within the R2 subunit; the radical is subsequently shuttled to the catalytic R1 subunit through proton-coupled electron transfer (PCET). We present a high-resolution room temperature structure of the class Ie R2 protein radical captured by x-ray free electron laser serial femtosecond crystallography. The structure reveals conformational reorganization to shield the radical and connect it to the translocation path, with structural changes propagating to the surface where the protein interacts with the catalytic R1 subunit. Restructuring of the hydrogen bond network, including a notably short O-O interaction of 2.41 angstroms, likely tunes and gates the radical during PCET. These structural results help explain radical handling and mobilization in RNR and have general implications for radical transfer in proteins.
- Published
- 2023
- Full Text
- View/download PDF
19. The Crystal Structure of Tyrosinase from Verrucomicrobium spinosum Reveals It to Be an Atypical Bacterial Tyrosinase.
- Author
-
Fekry M, Dave KK, Badgujar D, Hamnevik E, Aurelius O, Dobritzsch D, and Danielson UH
- Abstract
Tyrosinases belong to the type-III copper enzyme family, which is involved in melanin production in a wide range of organisms. Despite similar overall characteristics and functions, their structures, activities, substrate specificities and regulation vary. The tyrosinase from the bacterium Verrucomicrobium spinosum ( vs Tyr) is produced as a pre-pro-enzyme in which a C-terminal extension serves as an inactivation domain. It does not require a caddie protein for copper ion incorporation, which makes it similar to eukaryotic tyrosinases. To gain an understanding of the catalytic machinery and regulation of vs Tyr activity, we determined the structure of the catalytically active "core domain" of vs Tyr by X-ray crystallography. The analysis showed that vs Tyr is an atypical bacterial tyrosinase not only because it is independent of a caddie protein but also because it shows the highest structural (and sequence) similarity to plant-derived members of the type-III copper enzyme family and is more closely related to fungal tyrosinases regarding active site features. By modelling the structure of the pre-pro-enzyme using AlphaFold, we observed that Phe453, located in the C-terminal extension, is appropriately positioned to function as a "gatekeeper" residue. Our findings raise questions concerning the evolutionary origin of vs Tyr.
- Published
- 2023
- Full Text
- View/download PDF
20. A simple goniometer-compatible flow cell for serial synchrotron X-ray crystallography.
- Author
-
Ghosh S, Zorić D, Dahl P, Bjelčić M, Johannesson J, Sandelin E, Borjesson P, Björling A, Banacore A, Edlund P, Aurelius O, Milas M, Nan J, Shilova A, Gonzalez A, Mueller U, Brändén G, and Neutze R
- Abstract
Serial femtosecond crystallography was initially developed for room-temperature X-ray diffraction studies of macromolecules at X-ray free electron lasers. When combined with tools that initiate biological reactions within microcrystals, time-resolved serial crystallography allows the study of structural changes that occur during an enzyme catalytic reaction. Serial synchrotron X-ray crystallography (SSX), which extends serial crystallography methods to synchrotron radiation sources, is expanding the scientific community using serial diffraction methods. This report presents a simple flow cell that can be used to deliver microcrystals across an X-ray beam during SSX studies. This device consists of an X-ray transparent glass capillary mounted on a goniometer-compatible 3D-printed support and is connected to a syringe pump via light-weight tubing. This flow cell is easily mounted and aligned, and it is disposable so can be rapidly replaced when blocked. This system was demonstrated by collecting SSX data at MAX IV Laboratory from microcrystals of the integral membrane protein cytochrome c oxidase from Thermus thermophilus , from which an X-ray structure was determined to 2.12 Å resolution. This simple SSX platform may help to lower entry barriers for non-expert users of SSX., (© Swagatha Ghosh et al. 2023.)
- Published
- 2023
- Full Text
- View/download PDF
21. Redox-controlled reorganization and flavin strain within the ribonucleotide reductase R2b-NrdI complex monitored by serial femtosecond crystallography.
- Author
-
John J, Aurelius O, Srinivas V, Saura P, Kim IS, Bhowmick A, Simon PS, Dasgupta M, Pham C, Gul S, Sutherlin KD, Aller P, Butryn A, Orville AM, Cheah MH, Owada S, Tono K, Fuller FD, Batyuk A, Brewster AS, Sauter NK, Yachandra VK, Yano J, Kaila VRI, Kern J, Lebrette H, and Högbom M
- Subjects
- Crystallography, X-Ray, Flavins metabolism, Oxidation-Reduction, Superoxides, Ribonucleotide Reductases chemistry
- Abstract
Redox reactions are central to biochemistry and are both controlled by and induce protein structural changes. Here, we describe structural rearrangements and crosstalk within the Bacillus cereus ribonucleotide reductase R2b-NrdI complex, a di-metal carboxylate-flavoprotein system, as part of the mechanism generating the essential catalytic free radical of the enzyme. Femtosecond crystallography at an X-ray free electron laser was utilized to obtain structures at room temperature in defined redox states without suffering photoreduction. Together with density functional theory calculations, we show that the flavin is under steric strain in the R2b-NrdI protein complex, likely tuning its redox properties to promote superoxide generation. Moreover, a binding site in close vicinity to the expected flavin O
2 interaction site is observed to be controlled by the redox state of the flavin and linked to the channel proposed to funnel the produced superoxide species from NrdI to the di-manganese site in protein R2b. These specific features are coupled to further structural changes around the R2b-NrdI interaction surface. The mechanistic implications for the control of reactive oxygen species and radical generation in protein R2b are discussed., Competing Interests: JJ, OA, VS, PS, IK, AB, PS, MD, CP, SG, KS, PA, AB, AO, MC, SO, KT, FF, AB, AB, NS, VY, JY, VK, JK, HL, MH No competing interests declared, (© 2022, John et al.)- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.