Article
Chemistry, Multidisciplinary
Shari L. Meichsner, Yury Kutin, Muge Kasanmascheff
Summary: The study examined the essential radical Y-122 (center dot) in whole cells and found that its structure and distribution are consistent under in vivo and in vitro conditions. Experimental results also indicated a distinct in vivo Y-122 (center dot) per beta 2 distribution, highlighting the key role of Y-center dot concentrations in regulating RNR activity. Furthermore, the successful generation of an unnatural amino acid radical, F3Y122 center dot, in whole cells provides valuable insights into RNR catalysis under physiological conditions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Plant Sciences
Federica Frascogna, Benjamin Ledermann, Jana Hartmann, Eugenio Perez Patallo, Fjoralba Zeqiri, Eckhard Hofmann, Nicole Frankenberg-Dinkel
Summary: This study investigated the evolution of the HY2 lineage of FDBRs by studying the enzyme in Klebsormidium nitens. The research revealed that the catalytic activities of phytochromobilin synthase evolved differently in relation to the light environment of the organism.
Article
Multidisciplinary Sciences
Aidin R. Balo, Alessio Caruso, Lizhi Tao, Dean J. Tantillo, Mohammad R. Seyedsayamdost, R. David Britt
Summary: Using electron paramagnetic resonance (EPR) spectroscopy, this study dissected the mechanism of SuiB and revealed the essential role of the auxiliary [4Fe-4S] cluster in catalysis, confirming the proposed radical electrophilic aromatic substitution (rEAS) mechanism for the formation of the Lys-Trp cross-link. The findings provide direct evidence for the involvement of the SPASM domain auxiliary cluster and support rEAS as the mechanistic paradigm for rSAM enzyme-catalyzed carbon-carbon bond-forming reactions.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Chemistry, Inorganic & Nuclear
Diego R. Javier-Jimenez, Bryan T. Novas, Rory Waterman
Summary: The photocatalytic hydrophosphination activity of Cp2ZrCl2 and Cp*2ZrCl2 compounds was successfully induced by near ultraviolet (UV) irradiation, leading to the hydrophosphination of styrene substrates and activated alkenes. The irradiation caused homolysis of the Cp or Cp* ligand, resulting in radical hydrophosphination. The detection of this radical reactivity was achieved using in situ irradiation and monitoring for EPR signals, which proved to be a general methodology for determining radical versus closed-shell reactivity in transition-metal photocatalysis.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Biotechnology & Applied Microbiology
Jianfeng Mei, Xia Wu, Sujing Zheng, Yu Yi, Xudong Wang, Guoqing Ying
Summary: Bilirubin, a valuable Chinese medicine, is currently produced from pig bile, but due to raw material shortage, its price has increased. This study explores the use of biotransformation to produce bilirubin using recombinant E. coli expressing biliverdin reductase. With optimized conditions, the conversion yield reached 72.3%. This provides a potential alternative process for bilirubin production.
BIOPROCESS AND BIOSYSTEMS ENGINEERING
(2022)
Article
Multidisciplinary Sciences
Weiqing Zhang, Robert D. Willows, Rui Deng, Zheng Li, Mengqi Li, Yan Wang, Yunling Guo, Weida Shi, Qiuling Fan, Shelley S. Martin, Nathan C. Rockwell, J. Clark Lagarias, Deqiang Duanmu
Summary: The biosynthesis of chlorophyll and heme in oxygenic phototrophs follows a common pathway that diverges with the insertion of magnesium or iron. The interaction of bilins with GENOMES UNCOUPLED 4 (GUN4) stimulates the enzymatic activity of magnesium chelatase (MgCh) and stabilizes the accumulation of protoporphyrin IX-binding CrCHLH1 subunit of MgCh. GUN4: bilin complexes play dual regulatory roles in sustaining bilin biosynthesis and chlorophyll biosynthesis in illuminated oxic environments of all photosynthetic eukaryotes.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Mohamed A. Morsy, Abdel-Nasser M. Kawde, Muhammad Kamran, Thomas F. Garrison, Wissam Iali, Salman S. Alharthi
Summary: This work presents a method to monitor anthracene radical-mediated oxidation reactions using EPR spectroscopy, with detailed investigation of the reaction mechanism in concentrated sulfuric acid. The study identified the formation of the anthracene dimer product and characterized the EPR-spin transitions of the radical intermediate. Kinetic analysis revealed that radical intermediate formation is an autocatalytic process, dimerization is a pseudo-zero order reaction, and the rate-determining step has a half-life of 48 +/- 2 minutes at 25.0 degrees C.
Article
Microbiology
Lyndsay A. Carrigee, Jacob P. Frick, Xindi Liu, Jonathan A. Karty, Jonathan C. Trinidad, Irin P. Tom, Xiaojing Yang, Louison Dufour, Frederic Partensky, Wendy M. Schluchter
Summary: This article investigates the photosynthesis mechanism of marine Synechococcus cyanobacteria and discovers the different functions of the MpeV enzyme, which facilitates the linking and isomerization of pigments. Additionally, the authors find that the amino acid sequence of the PEI and PEII proteins plays a significant role in the isomerization reaction.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Chemistry, Physical
Carola S. Seelmann, Simona G. Huwiler, Martin Culka, Marc J. F. Strampraad, Till Biskup, Stefan Weber, G. Matthias Ullmann, Volker Schunemann, Peter-Leon Hagedoorn, Antonio J. Pierik, Matthias Boll
Summary: In anaerobic aromatic compound degrading microbes, class II benzoyl-coenzyme A (CoA) reductases (BCRs) reduce benzoyl-CoA to cyclohexa-1,5-diene-1-carboxyl-CoA (1,5-dienoyl-CoA) through a tungsten-bis-metallopterin (MPT) cofactor. This study provides experimental evidence for the Birch-like reduction mechanism via W(V)/radical intermediates and reveals the unique tetrahydro state of MPT cofactors essential for the reversibility of enzymatic Birch reduction.
Article
Chemistry, Multidisciplinary
Avijit Maiti, Benedict J. Elvers, Sachinath Bera, Felix Lindl, Ivo Krummenacher, Prasanta Ghosh, Holger Braunschweig, Cem B. Yildiz, Carola Schulzke, Anukul Jana
Summary: In this study, cyclic(alkyl)(amino)carbenes (CAACs) were found to be one-electron reductants, forming transient radical cations as detected by EPR spectroscopy. The reactivity of the disclosed CAACs was utilized to synthesize a new class of Thiele and Chichibabin hydrocarbons based on acyclic(amino)(aryl)carbene. Additionally, the acyclic(amino)(aryl)carbene-based Chichibabin's hydrocarbon showed a significant population of the triplet state at room temperature.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Philipp Lenz, Ryo Oshimizu, Sina Klabunde, Constantin G. Daniliuc, Christian Mueck-Lichtenfeld, Jonas C. Tendyck, Tatsuya Mori, Werner Uhl, Michael Ryan Hansen, Hellmut Eckert, Shigehiro Yamaguchi, Armido Studer
Summary: This article presents a new type of oxy-borylenes as photoreductants. Experimental results demonstrate that these oxy-borylenes can exhibit strong reducing capability under visible light, making them suitable for various reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Biochemistry & Molecular Biology
Flavia Agata Cimini, Antonella Tramutola, Ilaria Barchetta, Valentina Ceccarelli, Elena Gangitano, Simona Lanzillotta, Chiara Lanzillotta, Maria Gisella Cavallo, Eugenio Barone
Summary: BVRA protein levels can change dynamically in response to insulin and are greater in individuals with lower insulin sensitivity, indicating a correlation with insulin resistance and secretion.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Multidisciplinary
Li Feng Lim, Martyna Judd, Petra Vasko, Michael G. Gardiner, Dimitrios A. Pantazis, Nicholas Cox, Jamie Hicks
Summary: An isostructural series of heavy Group 14 E(I) radical anions (Ge, Sn, Pb), stabilized by a bulky xanthene-based diamido ligand, were synthesized and characterized. The E(II) precursor complexes were one-electron reduced with sodium naphthalenide in THF, yielding the charge-separated radical anions as sodium salts. The comprehensive characterization using EPR spectroscopy, X-ray crystallography, and DFT analysis revealed that the spin density of the unpaired electron is mainly located in a p-orbital of pi symmetry on the Group 14 center in all cases.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Microbiology
Wendy M. Schluchter, Courtney H. Babin, Xindi Liu, Amori Bieller, Gaozhong Shen, Richard M. Alvey, Donald A. Bryant
Summary: BvdR plays an important role in cyanobacteria by reducing biliverdin to bilirubin, a potent scavenger of reactive oxygen species (ROS). The presence of BvdR gene is observed in different strains of cyanobacteria and it has significant effects on the photosynthesis of cyanobacterial cells.
Article
Biochemistry & Molecular Biology
Keita Miyake, Hiroyuki Kimura, Rei Narikawa
Summary: This study identified a unique cyanobacteria, Acaryochloris marina, that uses chlorophyll d as its primary photosynthetic pigment, and discovered a specific mutation in the PcyA enzyme in this cyanobacteria, which may be related to its survival in long-wavelength far-red light environments.
PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
(2022)
Review
Microbiology
Francesca Cutruzzola, Nicole Frankenberg-Dinkel
JOURNAL OF BACTERIOLOGY
(2016)
Article
Chemistry, Multidisciplinary
Francisco Velazquez Escobar, Patrick Piwowarski, Johannes Salewski, Norbert Michael, Maria Fernandez Lopez, Anna Rupp, Bilal Muhammad Qureshi, Patrick Scheerer, Franz Bartl, Nicole Frankenberg-Dinkel, Friedrich Siebert, Maria Andrea Mroginski, Peter Hildebrandt
Article
Microbiology
Benjamin Ledermann, Oded Beja, Nicole Frankenberg-Dinkel
ENVIRONMENTAL MICROBIOLOGY
(2016)
Article
Biochemistry & Molecular Biology
Benjamin Ledermann, Meike Schwan, Johannes A. Sommerkamp, Eckhard Hofmann, Oded Beja, Nicole Frankenberg-Dinkel
Article
Biochemistry & Molecular Biology
Raphael Gasper, Julia Schwach, Jana Hartmann, Andrea Holtkamp, Jessica Wiethaus, Natascha Riedel, Eckhard Hofmann, Nicole Frankenberg-Dinkel
JOURNAL OF BIOLOGICAL CHEMISTRY
(2017)
Article
Biochemistry & Molecular Biology
Francisco Velazquez Escobar, David Buhrke, Norbert Michael, Luisa Sauthof, Svea Wilkening, Neslihan N. Tavraz, Johannes Salewski, Nicole Frankenberg-Dinkel, Maria Andrea Mroginski, Patrick Scheerer, Thomas Friedrich, Friedrich Siebert, Peter Hildebrandt
PHOTOCHEMISTRY AND PHOTOBIOLOGY
(2017)
Article
Biochemistry & Molecular Biology
Kerstin Fiege, Christine Joy Querebillo, Peter Hildebrandt, Nicole Frankenberg-Dinkel
Article
Biotechnology & Applied Microbiology
Judith Stiefelmaier, Benjamin Ledermann, Michael Sorg, Angela Banek, Doris Geib, Roland Ulber, Nicole Frankenberg-Dinkel
JOURNAL OF BIOTECHNOLOGY
(2018)
Article
Biochemistry & Molecular Biology
Kristina E. Overkamp, Raphael Gasper, Klaus Kock, Christian Herrmann, Eckhard Hofmann, Nicole Frankenberg-Dinkel
JOURNAL OF BIOLOGICAL CHEMISTRY
(2014)
Article
Microbiology
Kerstin Fiege, Nicole Frankenberg-Dinkel
ENVIRONMENTAL MICROBIOLOGY
(2019)
Article
Biochemistry & Molecular Biology
Marco Aras, Volker Hartmann, Jana Hartmann, Marc M. Nowaczyk, Nicole Frankenberg-Dinkel
Article
Biochemistry & Molecular Biology
Johannes A. Sommerkamp, Nicole Frankenberg-Dinkel, Eckhard Hofmann
JOURNAL OF BIOLOGICAL CHEMISTRY
(2019)
Article
Biotechnology & Applied Microbiology
Kerstin Fiege, Nicole Frankenberg-Dinkel
MICROBIAL CELL FACTORIES
(2020)
Article
Multidisciplinary Sciences
Vanessa Krauspe, Matthias Fahrner, Philipp Spat, Claudia Steglich, Nicole Frankenberg-Dinkel, Boris Macek, Oliver Schilling, Wolfgang R. Hess
Summary: The protein NblD plays a crucial role in the degradation of phycobilisomes in cyanobacteria under nitrogen-limited conditions. Studies have shown that NblD is essential for maintaining normal growth of cyanobacterial cells during nitrogen limitation.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Plant Sciences
Federica Frascogna, Benjamin Ledermann, Jana Hartmann, Eugenio Perez Patallo, Fjoralba Zeqiri, Eckhard Hofmann, Nicole Frankenberg-Dinkel
Summary: This study investigated the evolution of the HY2 lineage of FDBRs by studying the enzyme in Klebsormidium nitens. The research revealed that the catalytic activities of phytochromobilin synthase evolved differently in relation to the light environment of the organism.